C26Pinelake
BANNED
bet you are glad you went in with a low bid ! Every car gas its surprises, some good and some bad. Good luck and enjoy your new friend.
Wayne
Wayne
New car surprises . . .
- Thread starter Archie Cheda
- Start date
Archie Cheda
Member
Little surprises . . .
I received my pistons and they fit inside the block bores . . . actually it looks as if Badger intended them to be fit to .002" clearance, comparing their skirt diameter to the "3.9550" minimum bore" marked on the box. I'll side-step any argument by stating that in my block they will be running .004" by the time I have done my honing, but not much more. I'm glad I will be honing it -- the last guy achieved close to a zero-degree cross-hatch angle. (If you think about it, you have to go extremely slowly on your axial motion to get toward zero.) Hopefully I will not have piston slap when warmed up.
Ring gap checked out OK, but one ring had a burr on it that I filed off. Wrist pin clearance turned out to be well past a .001" typical wear limit, in the range of .002" to .003", so it looks as if I will be putting in new bushings. (I once had some 390 Ford rods re-bushed. They had .0015" clearance when I dropped them off at the machine shop. With new bushings installed and honed, they still had .0015" clearance. I asked the owner why I should be paying $90 to have my rods exactly the same as when I brought them in. Long story short, he clung to his stand that the rods would work fine and that he had done nothing wrong until I gave up and left forever.)
The main thing to share in this post is pictured below. Most engines I have ever had apart had factory numbers stamped on the rod caps, so I am assuming that some old-timers were in the habit of marking their rods with a filed groove on the beam side of the rods. This bothers me enough that I will be filing and polishing the marks off even though it might not cause too much trouble in a low rpm engine. There are two sets of marks, so when these rods go back in the engine, it will be at least their fourth time around . . .
Archie
P.S.: I will be weight-matching the pistons and rod ends.
I received my pistons and they fit inside the block bores . . . actually it looks as if Badger intended them to be fit to .002" clearance, comparing their skirt diameter to the "3.9550" minimum bore" marked on the box. I'll side-step any argument by stating that in my block they will be running .004" by the time I have done my honing, but not much more. I'm glad I will be honing it -- the last guy achieved close to a zero-degree cross-hatch angle. (If you think about it, you have to go extremely slowly on your axial motion to get toward zero.) Hopefully I will not have piston slap when warmed up.
Ring gap checked out OK, but one ring had a burr on it that I filed off. Wrist pin clearance turned out to be well past a .001" typical wear limit, in the range of .002" to .003", so it looks as if I will be putting in new bushings. (I once had some 390 Ford rods re-bushed. They had .0015" clearance when I dropped them off at the machine shop. With new bushings installed and honed, they still had .0015" clearance. I asked the owner why I should be paying $90 to have my rods exactly the same as when I brought them in. Long story short, he clung to his stand that the rods would work fine and that he had done nothing wrong until I gave up and left forever.)
The main thing to share in this post is pictured below. Most engines I have ever had apart had factory numbers stamped on the rod caps, so I am assuming that some old-timers were in the habit of marking their rods with a filed groove on the beam side of the rods. This bothers me enough that I will be filing and polishing the marks off even though it might not cause too much trouble in a low rpm engine. There are two sets of marks, so when these rods go back in the engine, it will be at least their fourth time around . . .
Archie
P.S.: I will be weight-matching the pistons and rod ends.
Attachments
tbirdtbird
BANNED
I feel certain that you will be very disappointed with either cam. You are knowledgeable enough to understand why.
Archie Cheda
Member
Weights & measures . . .
Let me preface this & future posts in this thread by saying that I am sharing what I am learning on this project in order to do my part to make information available. Most of the Model A-specific information I know has come from this forum and I am sorry if I cannot always properly credit the source, although I do try. (Sometimes I cannot find an old thread that I learned from, but I do look.) I am trying to post pics and details that I think will help beginners understand some of the very good advice on this forum. I am capable of error and ask that any errors be drawn to my attention. Like others, I am an expert on my own opinions, so remember I am not telling anyone what to do, or saying that anyone is wrong -- I am only sharing my understanding and what I am doing.
First I'll share a single point of data for those who like numbers. I literally boiled one of my new pistons to see how much it would grow. Going from 65 degrees to 212 (F), the top of the piston grew by .005". For the same temperature range the full-skirt, un-slotted piston grew .004" at its largest diameter. I am not making any major point here, just satisfying my curiosity and sharing what I found.
Having borrowed a nice digital postal scale, I weighed my new pistons as shown in the first pic -- they came in within a tenth of an ounce of 26.5 ounces. I then weighed my mis-matched used pistons -- the three-ring pair each came in within a tenth of an ounce of 25 ounces and the four-ring each came in at 28 ounces with another ounce to be added for the fourth ring. While this sounds disastrous, the builder was wise enough to pair the heavy ones in #1 & 2 cylinders and the light ones in #3 & 4 cylinders such that they were adjacent and moving in opposite directions. This would reduce, but not eliminate the effects of the imbalance.
The rods were a different story with overall weights of 25.4, 26.1, 26.1, and 27.1 ounces -- a maximum error of almost two ounces. I did not do separate weights for the big and small ends now until I checked out other things. Yesterday, I read a lot of threads regarding rods on this forum and someone stated something like: "If you can see that a rod is not straight, it is junk!"* I am sorry that am am able to document this sort of rod. The second pic shows a view along the length of the rod which brought my first doubt about this rod. The bends are visible, but a little hard to see, but it is obvious is that small end geometry is not quite right. Notice that the double-tapered shape of the external shape of the small end is not symmetrical. This bothered me because it is not the result of a dubious mechanic modifying an original part, but the small end's width is the same as the other rods, but is off center. To me this indicates that the rod was bent when it was first machined, although I am open to other thoughts. The third pic shows that a straight edge can be laid across the bottom and top rod ends, which seem to of very near the same width. I do not consider this to be more than a quick check, but it shows that the rod is not offset any large amount compared with the mis-match in the symmetry of this rod. Measuring from the plane of symmetry (the parting plane of the original forging), one side projects a full eighth of an inch more than the other. The other rods in this set do not fail this visual test. My plan is to see what I can turn up at the swap meet . . . I know a lot of folks might just advise that I get a new set of rods, but this is a hobby and I enjoy this process more than just spending money. (I already know how to do that!)
Finally the fourth pic is my setup for checking parallelism and twist of rods. When doing final checks on rods that I will be using, I will do the set-up twice to confirm that this set-up repeats the same measurements. For now, I just did a quick check of the one rod to see how bad it is. The parallelism between the piston pin and the crank-pin bore comes out to be .018" in the 3.5" length of the pin. A 4,000# axial load on the rod would result in a 20# side-force on the rod -- this is a quick calculation, but I wanted to get an idea of the size of this force. In a low rpm, low-stress Model A engine, I would not expect this amount of force to cause any immediate problem and this engine was running without major known problems when it was replaced as part of a restoration by my cousin. I am quite certain that this rod contributed to all those minor noises that one learns to accept with a less-than-perfect running engine. This engine is a step in my process: it will allow me to get familiar with Model A engines, then I will build my "good" engine", either stock or a bit warmed up. In any case I want it to be smooth and quiet and I am seeing how important some of these easy to overlook details can be.
Rotating the rod by 90 degrees, I was able to determine that the piston pin is out of the plane of the crank-pin bore by .043", which seems to be quite a lot. It would be a chore to calculate exactly how much this twist would reposition the piston in the bore during the stroke, but the fact that the piston survived in the running engine may be because there was sufficient clearance. I did not properly mark the pistons, so all I can do at this point is to say that some of the pistons had a clearance in the bore of some .010", which may have allowed the engine to run without self-destructing. It is my opinion that a really sad rod could bind up a tightly-fit new piston and cause some of the damage that is often found.
My bottom line with all this is to reinforce the earlier recommendations that rod alignment is not something to ignore.
Archie
P.S.: If anyone has one odd rod that is useable at .030" undersize (or more) on the babbitt, I would be willing to take it off your hands for a reasonable sum plus postage. Otherwise, I'll have one more thing to look for at the swap meet.
* I tracked this statement back to 1930 coupe and could not agree more.
Let me preface this & future posts in this thread by saying that I am sharing what I am learning on this project in order to do my part to make information available. Most of the Model A-specific information I know has come from this forum and I am sorry if I cannot always properly credit the source, although I do try. (Sometimes I cannot find an old thread that I learned from, but I do look.) I am trying to post pics and details that I think will help beginners understand some of the very good advice on this forum. I am capable of error and ask that any errors be drawn to my attention. Like others, I am an expert on my own opinions, so remember I am not telling anyone what to do, or saying that anyone is wrong -- I am only sharing my understanding and what I am doing.
First I'll share a single point of data for those who like numbers. I literally boiled one of my new pistons to see how much it would grow. Going from 65 degrees to 212 (F), the top of the piston grew by .005". For the same temperature range the full-skirt, un-slotted piston grew .004" at its largest diameter. I am not making any major point here, just satisfying my curiosity and sharing what I found.
Having borrowed a nice digital postal scale, I weighed my new pistons as shown in the first pic -- they came in within a tenth of an ounce of 26.5 ounces. I then weighed my mis-matched used pistons -- the three-ring pair each came in within a tenth of an ounce of 25 ounces and the four-ring each came in at 28 ounces with another ounce to be added for the fourth ring. While this sounds disastrous, the builder was wise enough to pair the heavy ones in #1 & 2 cylinders and the light ones in #3 & 4 cylinders such that they were adjacent and moving in opposite directions. This would reduce, but not eliminate the effects of the imbalance.
The rods were a different story with overall weights of 25.4, 26.1, 26.1, and 27.1 ounces -- a maximum error of almost two ounces. I did not do separate weights for the big and small ends now until I checked out other things. Yesterday, I read a lot of threads regarding rods on this forum and someone stated something like: "If you can see that a rod is not straight, it is junk!"* I am sorry that am am able to document this sort of rod. The second pic shows a view along the length of the rod which brought my first doubt about this rod. The bends are visible, but a little hard to see, but it is obvious is that small end geometry is not quite right. Notice that the double-tapered shape of the external shape of the small end is not symmetrical. This bothered me because it is not the result of a dubious mechanic modifying an original part, but the small end's width is the same as the other rods, but is off center. To me this indicates that the rod was bent when it was first machined, although I am open to other thoughts. The third pic shows that a straight edge can be laid across the bottom and top rod ends, which seem to of very near the same width. I do not consider this to be more than a quick check, but it shows that the rod is not offset any large amount compared with the mis-match in the symmetry of this rod. Measuring from the plane of symmetry (the parting plane of the original forging), one side projects a full eighth of an inch more than the other. The other rods in this set do not fail this visual test. My plan is to see what I can turn up at the swap meet . . . I know a lot of folks might just advise that I get a new set of rods, but this is a hobby and I enjoy this process more than just spending money. (I already know how to do that!)
Finally the fourth pic is my setup for checking parallelism and twist of rods. When doing final checks on rods that I will be using, I will do the set-up twice to confirm that this set-up repeats the same measurements. For now, I just did a quick check of the one rod to see how bad it is. The parallelism between the piston pin and the crank-pin bore comes out to be .018" in the 3.5" length of the pin. A 4,000# axial load on the rod would result in a 20# side-force on the rod -- this is a quick calculation, but I wanted to get an idea of the size of this force. In a low rpm, low-stress Model A engine, I would not expect this amount of force to cause any immediate problem and this engine was running without major known problems when it was replaced as part of a restoration by my cousin. I am quite certain that this rod contributed to all those minor noises that one learns to accept with a less-than-perfect running engine. This engine is a step in my process: it will allow me to get familiar with Model A engines, then I will build my "good" engine", either stock or a bit warmed up. In any case I want it to be smooth and quiet and I am seeing how important some of these easy to overlook details can be.
Rotating the rod by 90 degrees, I was able to determine that the piston pin is out of the plane of the crank-pin bore by .043", which seems to be quite a lot. It would be a chore to calculate exactly how much this twist would reposition the piston in the bore during the stroke, but the fact that the piston survived in the running engine may be because there was sufficient clearance. I did not properly mark the pistons, so all I can do at this point is to say that some of the pistons had a clearance in the bore of some .010", which may have allowed the engine to run without self-destructing. It is my opinion that a really sad rod could bind up a tightly-fit new piston and cause some of the damage that is often found.
My bottom line with all this is to reinforce the earlier recommendations that rod alignment is not something to ignore.
Archie
P.S.: If anyone has one odd rod that is useable at .030" undersize (or more) on the babbitt, I would be willing to take it off your hands for a reasonable sum plus postage. Otherwise, I'll have one more thing to look for at the swap meet.
* I tracked this statement back to 1930 coupe and could not agree more.
Attachments
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tbirdtbird
BANNED
speaking at least for myself I appreciate the effort, intelligence, and experience you are putting into this project and the documentation thereof. We don't usually get anywhere near this. Usually just a couple of sound bites and snipes and often no resolution to an issue is provided
Synchro909
Well-known member
Ditto Tbird.
What you are doing is about what I would do/have done. Good work which I'm sure will pay off later.
What you are doing is about what I would do/have done. Good work which I'm sure will pay off later.
Archie Cheda
Member
Still learning . . .
While I wait until the swap meet, I am still checking dimensions and parts. I can go ahead and hone the bore of my good block, but I need to resolve the cam and rod problems. While I am at it, I'll probably pull the cam and once I get into the valves I might even decide to do some valve work . . . I need to remember that this is supposed to be an overhaul . . .
With this in mind, I took a look at my cranks and rods. The counter-weighted crank & rod set are .020" undersize and the other is .030" undersize. Today I checked out all the journals and most of them are enough under nominal size that going with inserted bearings is not in the cards for either crank unless I grind to the next undersize. One thing I need to get used to is how much more flexible fitting bearings to journals is when scraping babbitt than when using inserts. I am beginning to think that I will go with inserts when I invest $$$ in a major rebuild, but for now I am wanting to get some babbitt scraping experience.
I would be interested in opinions about using inserts in a stock or mild (5.5 c/r & .330" lift cam) engine with an unpressurized oil system. This would be in a coupe that would not be subject to hard touring -- local trips at 55 mph max.
The rods that match my counter-weighted crank are very nice compared to the other set. I would re-bush and re-scrape them and check alignment. They all weigh within a tenth of an ounce of each other and show obvious signs of being weight-matched recently. The counter-weights also show fresh balancing holes. The whole bottom end of the rods still show that they were tinned when they were re-babbitted. On the other hand, the wrist pin bushings are far from being usable with over .002" of clearance and the grooving is only a simple groove down the center of the cap babbitt -- no X groove and no chamfering. All of this is easily "fixable", so I am now considering using the counter-weighted crank & rods. The only down-side is that I will have to line bore the .030" mains in my un-cracked block to .020" and fit the crank, but this is all within the realm of possibility, although it may end up being both my first and last adventure in babbitt.
If the engine runs well, it might be a long time before I get to the next step . . .
Archie
While I wait until the swap meet, I am still checking dimensions and parts. I can go ahead and hone the bore of my good block, but I need to resolve the cam and rod problems. While I am at it, I'll probably pull the cam and once I get into the valves I might even decide to do some valve work . . . I need to remember that this is supposed to be an overhaul . . .
With this in mind, I took a look at my cranks and rods. The counter-weighted crank & rod set are .020" undersize and the other is .030" undersize. Today I checked out all the journals and most of them are enough under nominal size that going with inserted bearings is not in the cards for either crank unless I grind to the next undersize. One thing I need to get used to is how much more flexible fitting bearings to journals is when scraping babbitt than when using inserts. I am beginning to think that I will go with inserts when I invest $$$ in a major rebuild, but for now I am wanting to get some babbitt scraping experience.
I would be interested in opinions about using inserts in a stock or mild (5.5 c/r & .330" lift cam) engine with an unpressurized oil system. This would be in a coupe that would not be subject to hard touring -- local trips at 55 mph max.
The rods that match my counter-weighted crank are very nice compared to the other set. I would re-bush and re-scrape them and check alignment. They all weigh within a tenth of an ounce of each other and show obvious signs of being weight-matched recently. The counter-weights also show fresh balancing holes. The whole bottom end of the rods still show that they were tinned when they were re-babbitted. On the other hand, the wrist pin bushings are far from being usable with over .002" of clearance and the grooving is only a simple groove down the center of the cap babbitt -- no X groove and no chamfering. All of this is easily "fixable", so I am now considering using the counter-weighted crank & rods. The only down-side is that I will have to line bore the .030" mains in my un-cracked block to .020" and fit the crank, but this is all within the realm of possibility, although it may end up being both my first and last adventure in babbitt.
If the engine runs well, it might be a long time before I get to the next step . . .
Archie
tbirdtbird
BANNED
"I would be interested in opinions about using inserts in a stock or mild (5.5 c/r & .330" lift cam) engine with an unpressurized oil system. This would be in a coupe that would not be subject to hard touring -- local trips at 55 mph max."
This used to bother me as well until I had lots of conversations with the local Dallas club gurus. The gravity oiling system works way better than you might think. You can run C/R up to 7.0 on a gravity system, and babbitt or shells with either oiling, and .330 lift cam with either oiling. We have lots of members with various combinations of these items. I myself have gravity feed babbitt, a .330 lift cam, having no problems, and will be installing a Snyder 6.0 head within a week. I do 60-65 all day (also have a Mitchell and I have a self-imposed red line of 2400). I tour several thousand miles a yr and there are members who do more than that.
Miles is having an inserted motor built with the same specs (6.0 head and .330 cam, and gravity feed oil), and once that is done I am getting an identical motor. We will be opting for the BB counterweighting system on an A crank. One of our members won the great race a couple times in his class with a Model A racer and is very knowledgeable. I talk to him all the time.
Pete and Jim B race and might add some comments. dave
This used to bother me as well until I had lots of conversations with the local Dallas club gurus. The gravity oiling system works way better than you might think. You can run C/R up to 7.0 on a gravity system, and babbitt or shells with either oiling, and .330 lift cam with either oiling. We have lots of members with various combinations of these items. I myself have gravity feed babbitt, a .330 lift cam, having no problems, and will be installing a Snyder 6.0 head within a week. I do 60-65 all day (also have a Mitchell and I have a self-imposed red line of 2400). I tour several thousand miles a yr and there are members who do more than that.
Miles is having an inserted motor built with the same specs (6.0 head and .330 cam, and gravity feed oil), and once that is done I am getting an identical motor. We will be opting for the BB counterweighting system on an A crank. One of our members won the great race a couple times in his class with a Model A racer and is very knowledgeable. I talk to him all the time.
Pete and Jim B race and might add some comments. dave
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tbirdtbird
BANNED
BTW Archie, after digging all the grit out of the valve chamber and dipper tray I am sure you have at least considered the oil filter option
Archie Cheda
Member
Skip this post if you do not like stories . . .
in 1966 I worked piecework for a used car lot to cover my college textbooks. One morning about ten my buddy & I pulled the 292 Y-block out of a 1957 hard-top convertible with shot bearings. We set the engine upside-down on its valve covers and pulled the crank. We drove five miles to fetch a crank kit and while my buddy was paying, I happened to stick my finger in the hollow throw of the crank and found that I could see my finger through one of the drilled oil holes. I asked the very experienced old-timer about this. He took back the crank and gave us another explaining that it was a welded crank and after the welding, the oil hole would have to have been opened up. He postulated that that it was probably the first day on the job for the guy that drilled the hole and he did not realize that he was supposed to drill at the proper angle and had just drilled radially. He said that one would be surprised how long this crank would have lasted with one bearing only receiving oil from its adjacent bearing. He said that with mild use it would have been many thousands of miles. (End of story: we re-installed the crank and had the car running by two that afternoon. This was in those days when we were not afraid of anything and the thought of keeping sixteen rod bolts from dinging a fresh crank did not daunt us at all . . .)
The idea of a rod bearing surviving without pressurized oil delivery, planted in my mind when I was twenty, is still with me when I think about various plane journal bearings in machine tools and "dip-splash" automotive applications. Most folks think that the pressure from the pump is the main thing going on in automotive crankshaft bearings, but there are many examples where the oil pressure and volume are low and the load & rpm are significant. So long as enough oil is delivered to keep ahead of losses, it is the relative motion that creates the hydrodynamic effect. Of course when it comes to racing or other extreme loading conditions, one may need to move a lot of oil through the bearing to keep things cool. Bearing area and proportions have a lot to do with how much oil is needed and this can be seen if one follows the evolution of plane journal bearings. Bottom line for me is that if the inserts have the same proportion as the babbitt bearings, the oil should still do its job of keeping moving parts from contacting each other. Babbitt still eats dirt better, so inserts require cleaner, filtered oil.
Archie
P.S.: tbdbd, thanks for the anecdotal support for non-high-pressure inserts -- I think that I will be going that way, partly because it is what I know best, but mainly because it does not lock an engine into a particular set of journal undersizes, some of which may not even be nominal. I do not plan on doing a lot of crank swapping, but one never knows. This same kind of thinking leads me to drift away from the idea of using a Stipe cam with oversized bearing journals with a custom line bore size in the block. For a bit more effort, I can line bore oversize for inserts and use any stock cam. Even if I need to make my own inserts, this appeals to me. (Still considering a Stipe IB-330.)
in 1966 I worked piecework for a used car lot to cover my college textbooks. One morning about ten my buddy & I pulled the 292 Y-block out of a 1957 hard-top convertible with shot bearings. We set the engine upside-down on its valve covers and pulled the crank. We drove five miles to fetch a crank kit and while my buddy was paying, I happened to stick my finger in the hollow throw of the crank and found that I could see my finger through one of the drilled oil holes. I asked the very experienced old-timer about this. He took back the crank and gave us another explaining that it was a welded crank and after the welding, the oil hole would have to have been opened up. He postulated that that it was probably the first day on the job for the guy that drilled the hole and he did not realize that he was supposed to drill at the proper angle and had just drilled radially. He said that one would be surprised how long this crank would have lasted with one bearing only receiving oil from its adjacent bearing. He said that with mild use it would have been many thousands of miles. (End of story: we re-installed the crank and had the car running by two that afternoon. This was in those days when we were not afraid of anything and the thought of keeping sixteen rod bolts from dinging a fresh crank did not daunt us at all . . .)
The idea of a rod bearing surviving without pressurized oil delivery, planted in my mind when I was twenty, is still with me when I think about various plane journal bearings in machine tools and "dip-splash" automotive applications. Most folks think that the pressure from the pump is the main thing going on in automotive crankshaft bearings, but there are many examples where the oil pressure and volume are low and the load & rpm are significant. So long as enough oil is delivered to keep ahead of losses, it is the relative motion that creates the hydrodynamic effect. Of course when it comes to racing or other extreme loading conditions, one may need to move a lot of oil through the bearing to keep things cool. Bearing area and proportions have a lot to do with how much oil is needed and this can be seen if one follows the evolution of plane journal bearings. Bottom line for me is that if the inserts have the same proportion as the babbitt bearings, the oil should still do its job of keeping moving parts from contacting each other. Babbitt still eats dirt better, so inserts require cleaner, filtered oil.
Archie
P.S.: tbdbd, thanks for the anecdotal support for non-high-pressure inserts -- I think that I will be going that way, partly because it is what I know best, but mainly because it does not lock an engine into a particular set of journal undersizes, some of which may not even be nominal. I do not plan on doing a lot of crank swapping, but one never knows. This same kind of thinking leads me to drift away from the idea of using a Stipe cam with oversized bearing journals with a custom line bore size in the block. For a bit more effort, I can line bore oversize for inserts and use any stock cam. Even if I need to make my own inserts, this appeals to me. (Still considering a Stipe IB-330.)
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tbirdtbird
BANNED
"So long as enough oil is delivered to keep ahead of losses, it is the relative motion that creates the hydrodynamic effect."
You are way ahead of the curve. This is exactly what is going on, the hydrodynamic wedge rules the roost!
good luck and keep us posted. I enjoy reading what you are doing.
You are way ahead of the curve. This is exactly what is going on, the hydrodynamic wedge rules the roost!
good luck and keep us posted. I enjoy reading what you are doing.
Archie Cheda
Member
Waiting for the Turlock Swap Meet . . .
While I wait for the big event in Turlock, I have been killing time and now have the second engine 100% disassembled . . . I find that Model A engines continue to have the capacity to surprise me . . .
Using Snyder's numbers for what constitutes a good cam core, I find that neither of my cams are even close on either lobe size or journal diameter. (This is not really a new surprise as I already decided that these cams had been re-ground at least once.)
The cam gear is a "Westinghouse Micarta Gear" and is of two-piece construction with a metal hub. It is reinforced by woven fibers, not macerated fibers. adI have heard of these on the forum, but thought I'd share a pic of one that has not failed. The gear looks OK, but I have heard of enough failures that I do not think I will trust it -- I have a new Al/Steel pair on hand. (Opinions welcome . . .) (Anyone surprised that the old-style cam nut is not all beat up?)
I found that the cam center bore was worn .004", but only in the vertical direction. (The center cam journal was worn .006".) For this overhaul, I think I will accept the loss of oil through this bearing -- the cam should not really move around much as the spring thrust through the "push rods" (tappets) should keep the cam against the lower end of the oval bore it rides in. (This assumes I can find a cam that is not in bad shape.)
I noticed perceptible side play in the tappets and found .003" clearance. Again, this is an overhaul, so I will wait until I do my complete rebuild before I address this sort of problem. It looks as if Chrysler mushroom tappets are a good fix, but the prices I am finding are so high, so I may just end up putting in sleeves -- remember, my time cost me nothing and doing this sort of work keeps me out of trouble . . .
While removing the head studs, I did manage to break two, even though I did a lot of soaking, tapping, and heating. I know that "welding a nut on it" is not a new trick, but I share a pic or the "bolts" I ended up with to encourage others to use this method. I used stick welding with 1/8" E8018. It did take quite a number of attempts, but upon analyzing the nuts that broke free without removing the stud, half of them were poor welds, but the other half were pretty solid. My take is that several cycles of heating may be necessary to free up a well-siezed stud. I did not use a washer and used 1/2-13 nuts. I have not done this before now, but a friend of my Dad's who was an outstanding welder, was doing this over 60 years ago. He could even pull out the broken piece in an OHV engine without removing the head -- I would not suggest that most of us try to "do this at home". Notice in the pics, the unthreaded portion of the "bolt" shank" is weld metal as the studs were broken 1/8" below the deck surface. There was no damage to the block. (The hard part is striking the arc without moving the nut -- practice, practice, practice . . .)
Archie
P.S.: With the keepers and springs off of the valves, I found that the guides are pretty bad and the valves have almost no margin, so I will be putting in new guides and valves. I think I'll go "old school" this time around, but one-piece, pressed in guides and modern keepers will be what I'll use for the next engine, which will be at least a year out.
While I wait for the big event in Turlock, I have been killing time and now have the second engine 100% disassembled . . . I find that Model A engines continue to have the capacity to surprise me . . .
Using Snyder's numbers for what constitutes a good cam core, I find that neither of my cams are even close on either lobe size or journal diameter. (This is not really a new surprise as I already decided that these cams had been re-ground at least once.)
The cam gear is a "Westinghouse Micarta Gear" and is of two-piece construction with a metal hub. It is reinforced by woven fibers, not macerated fibers. adI have heard of these on the forum, but thought I'd share a pic of one that has not failed. The gear looks OK, but I have heard of enough failures that I do not think I will trust it -- I have a new Al/Steel pair on hand. (Opinions welcome . . .) (Anyone surprised that the old-style cam nut is not all beat up?)
I found that the cam center bore was worn .004", but only in the vertical direction. (The center cam journal was worn .006".) For this overhaul, I think I will accept the loss of oil through this bearing -- the cam should not really move around much as the spring thrust through the "push rods" (tappets) should keep the cam against the lower end of the oval bore it rides in. (This assumes I can find a cam that is not in bad shape.)
I noticed perceptible side play in the tappets and found .003" clearance. Again, this is an overhaul, so I will wait until I do my complete rebuild before I address this sort of problem. It looks as if Chrysler mushroom tappets are a good fix, but the prices I am finding are so high, so I may just end up putting in sleeves -- remember, my time cost me nothing and doing this sort of work keeps me out of trouble . . .
While removing the head studs, I did manage to break two, even though I did a lot of soaking, tapping, and heating. I know that "welding a nut on it" is not a new trick, but I share a pic or the "bolts" I ended up with to encourage others to use this method. I used stick welding with 1/8" E8018. It did take quite a number of attempts, but upon analyzing the nuts that broke free without removing the stud, half of them were poor welds, but the other half were pretty solid. My take is that several cycles of heating may be necessary to free up a well-siezed stud. I did not use a washer and used 1/2-13 nuts. I have not done this before now, but a friend of my Dad's who was an outstanding welder, was doing this over 60 years ago. He could even pull out the broken piece in an OHV engine without removing the head -- I would not suggest that most of us try to "do this at home". Notice in the pics, the unthreaded portion of the "bolt" shank" is weld metal as the studs were broken 1/8" below the deck surface. There was no damage to the block. (The hard part is striking the arc without moving the nut -- practice, practice, practice . . .)
Archie
P.S.: With the keepers and springs off of the valves, I found that the guides are pretty bad and the valves have almost no margin, so I will be putting in new guides and valves. I think I'll go "old school" this time around, but one-piece, pressed in guides and modern keepers will be what I'll use for the next engine, which will be at least a year out.
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Archie Cheda
Member
Oversize tappets . . .
I just found that Mac's and Snyders offer .005" oversize tappets ("pushrods").
Does anyone know what their base diameter is?
(Does not make sense to me to make tappets with an oversized shank and undersized base. . .)
Thanks,
Archie
I just found that Mac's and Snyders offer .005" oversize tappets ("pushrods").
Does anyone know what their base diameter is?
(Does not make sense to me to make tappets with an oversized shank and undersized base. . .)
Thanks,
Archie
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tbirdtbird
BANNED
Great stuff.
As you already know that gear with the metal center is trash.
E8018...heavy duty stuff. 1/8 stick amazes me I could have done that yrs ago but once i went to MIG my stick machine just gathers dust. Way easier with a MIG but you got it done, that is what counts. I remember a guy switching me from stick to MIG...i was very concerned about something new and would I be able to make it work....hell it is like child's play!!
There is a guy on this forum that thinks he can weld hi-grade alloys like tool steel with 6013 rods.... I am sure he will chime in soon. You and I both know such a weld will fracture very quickly if low-H rod is not used.
as far as the base of the lifters be sure to check with the suppliers, you never can be too sure.
you are on the right track, for sure
Oh, and consider cutting your lifter bosses down 3/8 of an inch. That is what we all do around here, makes adjusting lash WAY easier. There are a few on the forum who are absolutely against this, just FYI. You will hear from them soon. But none of us have ever had a problem. Jim B and Pete might chime in I am sure they do. You might get Jim Bs book, he races As. I personally do not cut the 2 bosses that are embedded in the dams
haha another poster replied to me once that, "well we don't all race our As, so we don't care what the racers are doing." You'll hear from him, too. Cough cough every advance in automotive history has come from the racers; they are ahead of the curve. OF COURSE we don't all race our As. You missed the point. They have come up with engine improvements that can benefit everyone.
As you already know that gear with the metal center is trash.
E8018...heavy duty stuff. 1/8 stick amazes me I could have done that yrs ago but once i went to MIG my stick machine just gathers dust. Way easier with a MIG but you got it done, that is what counts. I remember a guy switching me from stick to MIG...i was very concerned about something new and would I be able to make it work....hell it is like child's play!!
There is a guy on this forum that thinks he can weld hi-grade alloys like tool steel with 6013 rods.... I am sure he will chime in soon. You and I both know such a weld will fracture very quickly if low-H rod is not used.
as far as the base of the lifters be sure to check with the suppliers, you never can be too sure.
you are on the right track, for sure
Oh, and consider cutting your lifter bosses down 3/8 of an inch. That is what we all do around here, makes adjusting lash WAY easier. There are a few on the forum who are absolutely against this, just FYI. You will hear from them soon. But none of us have ever had a problem. Jim B and Pete might chime in I am sure they do. You might get Jim Bs book, he races As. I personally do not cut the 2 bosses that are embedded in the dams
haha another poster replied to me once that, "well we don't all race our As, so we don't care what the racers are doing." You'll hear from him, too. Cough cough every advance in automotive history has come from the racers; they are ahead of the curve. OF COURSE we don't all race our As. You missed the point. They have come up with engine improvements that can benefit everyone.
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pat in Santa Cruz
Well-known member
It sounds like you appreciate quality. If you can find a Stipe 330 cam, you will not regret using one. I forgot all about the price after I finally bit the bullet and bought one. You also might want to talk to Dan McEachern about a set of his gears. He'll have you measure the ctr to ctr of the cam and crank in case they were ever line bored out of spec. He can make a custom set if needed so you will have quiet metal gears. If your centers are good, he has beautiful gears immediately available for that.
I agree on cutting the lifter bosses and be certain the lifter foot is 1 1/8th. Most are now, but there might still be some old stock with 1 inch foot out there.
I agree on cutting the lifter bosses and be certain the lifter foot is 1 1/8th. Most are now, but there might still be some old stock with 1 inch foot out there.
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pat in Santa Cruz
Well-known member
Hey, Tom ! I like that shot of my crummy tenni.
Archie Cheda
Member
Turlock booty . . .
In an efficient half-day sweep, I found a camshaft and also bought the crankshaft that was with it to keep it company on the way home . . .
As you can see in the first pic, they would not win any beauty prizes, but the camshaft meets Snyder's requirements for a re-grind core and the crank is standard on the rods and mains.
Two passes with Naval jelly cleaned up most of the rust (see insert) and the end journals are only a thousandth or so under, with the middle squeaking through at .003" under.The base circles are all within a thousandth or so and are the nominal size of an original cam -- this cam has not been reground at all. The lifts are all between .275" and .280" -- 91% to 93% of stock lift. I think I may just run this cam as it is in my stock overhauled engine.
I only found one set of A rods and they were .010" under. I would gladly pay a good price for one .030" under rod with usable babbitt. I'll be re-bushing it, so as long as it is visually straight & otherwise acceptable it should be OK. I will also go for an .040" under rod as I can bore it to .030". (Yes, I did post a wanted ad . . .)
I can use my counterweighted crank & rods, but I really would like to overhaul a more or less completely stock engine first so I will know just how much to "warm it up", if any.
Thanks,
Archie
In an efficient half-day sweep, I found a camshaft and also bought the crankshaft that was with it to keep it company on the way home . . .
As you can see in the first pic, they would not win any beauty prizes, but the camshaft meets Snyder's requirements for a re-grind core and the crank is standard on the rods and mains.
Two passes with Naval jelly cleaned up most of the rust (see insert) and the end journals are only a thousandth or so under, with the middle squeaking through at .003" under.The base circles are all within a thousandth or so and are the nominal size of an original cam -- this cam has not been reground at all. The lifts are all between .275" and .280" -- 91% to 93% of stock lift. I think I may just run this cam as it is in my stock overhauled engine.
I only found one set of A rods and they were .010" under. I would gladly pay a good price for one .030" under rod with usable babbitt. I'll be re-bushing it, so as long as it is visually straight & otherwise acceptable it should be OK. I will also go for an .040" under rod as I can bore it to .030". (Yes, I did post a wanted ad . . .)
I can use my counterweighted crank & rods, but I really would like to overhaul a more or less completely stock engine first so I will know just how much to "warm it up", if any.
Thanks,
Archie
Attachments
Tom Wesenberg
Well-known member
I bought a jar of Naval Jelly many years ago, but I never had much luck with it removing rust. I wonder if it has a short shelf life?
Archie Cheda
Member
De-rusting . . .
Tom,
Naval Jelly is just an expensive way to buy phosphoric acid -- it is jelled so it does not run off, so it is worth the extra cost for many uses. I cycle through brushing it on and "stirring" it with a brush so that the portion near the rusted surface gets turned over. As the pink jelly removes the oxygen from the rust, it loses its pink color and does not do much more. Always avoid letting it dry out. Today, I did the application for about ten minutes each time before rinsing with water and then lightly wire wheeling with light pressure to remove the loose material. As the acid reduces the rust by removing the oxygen, you are left with powdered iron which appears to be black. Unfortunately this is the original iron from the surface of the part, but cannot be re-joined to the steel or cast iron.
(Skip this if not interested in more technical info: Actually there are two forms of iron oxide or rust: one is the orange Fe302 and the other is black Fe3O4 and you want to remove both so that there is a much lighter colored surface of steel or cast iron. Because of rust pitting, the surface will usually be dull rather than the original shiny machined surface. Steel can pit deeply, but cast iron is usually only surface rust without much pitting. For bearing surfaces, it is a good idea to polish the surface so long as tolerances and clearances are not a problem. In most cases minor pitting does not interfere with the function and may even help hold oil. As far as what acid to use, citric acid {lemon juice} and acetic acid {vinegar} are very mild acids that are safe to use and good for fragile parts, but take much more time. Hydrochloric acid might be used by the impatient, but it is seriously dangerous stuff and its fumes will cause any bare metal near by to rust. Other stronger acids are way too much trouble to work with.)
There are other good ways to de-rust things, including other acids and electrolytic de-rusting. All of these methods may introduce atomic hydrogen into the material which can be a problem in hardened steels under loads. A simple bake within four hours (400 degrees for an hour is what I remember, but please correct me it you have better information) will allow this hydrogen to escape without increasing chance of cracking. The short exposure to a mild acid is probably not a problem, but I baked my cam is in the oven as cheap insurance . . .
Archie
Tom,
Naval Jelly is just an expensive way to buy phosphoric acid -- it is jelled so it does not run off, so it is worth the extra cost for many uses. I cycle through brushing it on and "stirring" it with a brush so that the portion near the rusted surface gets turned over. As the pink jelly removes the oxygen from the rust, it loses its pink color and does not do much more. Always avoid letting it dry out. Today, I did the application for about ten minutes each time before rinsing with water and then lightly wire wheeling with light pressure to remove the loose material. As the acid reduces the rust by removing the oxygen, you are left with powdered iron which appears to be black. Unfortunately this is the original iron from the surface of the part, but cannot be re-joined to the steel or cast iron.
(Skip this if not interested in more technical info: Actually there are two forms of iron oxide or rust: one is the orange Fe302 and the other is black Fe3O4 and you want to remove both so that there is a much lighter colored surface of steel or cast iron. Because of rust pitting, the surface will usually be dull rather than the original shiny machined surface. Steel can pit deeply, but cast iron is usually only surface rust without much pitting. For bearing surfaces, it is a good idea to polish the surface so long as tolerances and clearances are not a problem. In most cases minor pitting does not interfere with the function and may even help hold oil. As far as what acid to use, citric acid {lemon juice} and acetic acid {vinegar} are very mild acids that are safe to use and good for fragile parts, but take much more time. Hydrochloric acid might be used by the impatient, but it is seriously dangerous stuff and its fumes will cause any bare metal near by to rust. Other stronger acids are way too much trouble to work with.)
There are other good ways to de-rust things, including other acids and electrolytic de-rusting. All of these methods may introduce atomic hydrogen into the material which can be a problem in hardened steels under loads. A simple bake within four hours (400 degrees for an hour is what I remember, but please correct me it you have better information) will allow this hydrogen to escape without increasing chance of cracking. The short exposure to a mild acid is probably not a problem, but I baked my cam is in the oven as cheap insurance . . .
Archie