Can you run an A wide open?

[Kohnke Rebabbitting]

Hi Herm,

You were looking in the wrong place based on modern methods. Note the circumferential grind marks on the edges of both ends of the connecting rod. This was the last stage and when you study original rods you will find no two identical. The amount of "meat" removed is based on the particular weight removal requirements. I'd love to see the original machine. The machine certainly must have been automatic like the piston balancing machine which weighed the shavings and quit when the shavings weighed the same amount as the determined excessive weight.

At the beginning of production Ford balanced connecting rods in sets of four. They made it very clear to the dealers that they MUST replace connecting rods in complete sets to maintain the proper balance. Ford worked out their production / balancing methods and began making ALL connecting rods the same weight beginning April 24, 1928. They began providing the same for service May 10, 1928.

Marco, the message I left Kev, explains why I never seen to much balance in the Model A rods. I guess the thing I would ask you is who did your rebuilt rods, did they still have there right box. I have seen several rods like that, but never a shipping box. thanks Herm.

 

[Barry in St.Paul]

i ran mine out yesterday . about 75 mph , but its the first & only time ill do it . not comfortable for me or my car at that speed ................ me & my car love 55-60 mph . ....... steve

Steve, I'm curious what carb you are using? I have a high-speed (3.54) rear-end, Brumfield 5.9 head and touring cam, and "wide open" on flat road I seem to top out at about 60-65mph. But, it seems it is simply the limit of my Zenith carb. Wondering if you are using a Zenith or a Tilly? I don't care to drive any faster than I can go now, just curious :- )
thanks!

 

[Ryan]

I deleted some posts here fellas... I just have a low tolerance level for drama...

Carry on... without the name calling of course.

 

[Larry Brumfield]

Yo, Larry, I am sorry the 42 year comment didn't do anything for you, you'll be glad to know I tried it on my girl friend this afternoon, and it didn't do anything for her either, so I went down my list of known workable things, and found one she did like. I was going to thank you for the smart S.O.B. comment, but after I reread it a couple of times, I realized that you probably forgot a word in that sentence. You are wrong about learning what I know in 5 years, it was more like two years, I was lucky to have a Clawson & Bals babbitt trouble shooter teach me, and he sold me all Clawson & Bals machines, that he was going to use, but didn't get to after his retirement, from then on the learning part is mostly being able to tell when a pour is good, as every bearing pours different, temperature, to fast, to slow, cool to fast, not fast enough ect. In your opinion Larry the thinner the babbitt the better, and that is just what it is, Your Opinion, has nothing to do with Reality. If we were not to rebuild thick babbitt bearings, 60% of the bearings we do would never let there engine run again. Most of the cars, tractors, and machinery from 1900 to into the 1920's were real thick babbitt, and or thick babbitted shells. the big old tractors, some of them 3/8, to 1/2 inch babbitt thickness in rods and mains, and they are no better or worse than the model A. When babbitt thickness is cut, in factory engine building, it was mostly done to save money. 216's Chevy rods, from 1937 to 1953, have about .010 wall thickness of babbitt, and that works just fine, as they were all done at the Chevy factory, or a place they farmed them out to. The problem with rebuilding them the first time, is that you can't hit the same hole, as it were. So the 216's are bored to 100 thousands over standard bore with out babbitt. so there goes your thick babbitt that won't work again, BUT IT DOES. The babbitt wall now is .060 thousands thick instead of .010 thousands in a factory untouched rod. So Larry, in 42 years, and NO bad bearings EVER, in your experience what am I doing wrong. As far as an engine rebuilder ever being at fault, we stand behind every bearing we do. Babbitt bearing are just like insert bearings, in that if you have a bearing blow, weather babbitt, or insert you normally can tell why, just like an insert book, that has many pictures showing inserts, and there cause of failure. As far as an engine rebuilder never being at fault, the owner has to take some of the fault, as if his wife is a real you now what, just remember he picked her. Thanks Larry Jack, Gomer.

Ryan, allow me to tone things down a bit. The following needs to be said:

I never said that thick babbitt would not work ... and at the same time my other comments about babbitt are the exact truth!

Take the time to reread my posts and look for the words "apt", "possibly" and "IF the crank was off center a little bit or distorted in its operation for one reason or another."

You will see that I did not say that thick babbitt would fail on the average Model A out there on the street. If one were driven at a reasonable speed and load it would run just fine with thick babbitt UNLESS it had the problems that I alluded to in my posts. And if you'll reread everything you will see that I didn't say that bearing failure was a done deal even with the problems, I said "possibly."

Out on the dirt track using a Model A engine (in a different type car) I've had problems with toothpick cranks and thick babbitt.

I also don't believe there's never been a bad bearing in 42 years ..... he just never heard about it, that's all. Some people won't report anything and others will report the slightest problem.

For yet another man's experience instead of mine, go to and read what a renown automotive engineer knows about thick babbitt and the Model A. Click on the link below and then scroll down to where it says NOS Cap Showing Original Babbitt Thickness.

http://idisk.mac.com/forever4/Public/pages/bearingshims.htm


Larry B.

 

[Kohnke Rebabbitting]

Ryan, allow me to tone things down a bit. The following needs to be said:

I never said that thick babbitt would not work ... and at the same time my other comments about babbitt are the exact truth!

I also don't believe there's never been a bad bearing in 42 years ..... he just never heard about it, that's all. Some people won't report anything while others will report the slightest problem.

Kohnke is not the only person with engine experience.


Larry B.

Ryan, allow me to tone things down a bit. The following needs to be said END QUOTE) Dear, Dear Lar. I do so love the way you have of toning things down, you are SUCH a card.

(QUOTE) I never said that thick babbitt would not work ... and at the same time my other comments about babbitt are the exact truth! (END QUOTE) Lar, Lar, that is your truth, has nothing to do with Reality. There are many people like that, that Misdiagnosis a failure. IT IS ALWAYS, to much clearance, THAT WILL HAMMER IT OUT OR, NOT enough clearance that smears the babbitt, and then when the babbitt gets hard again, "IF IT COOLS" all the little smear granular pieces break off, and go back through the bearing again, and eat it up. Bad installation of the babbitt, that is the biggest fault of bearing failure, " If everything else is right" THERE HAS NEVER BEEN A BABBITT BEARING IN THIS WORLD FAIL BECAUSE OF THICKNESS. All REASONS that take out modern insert bearings, take out babbitt, except modern inserts can spin, an babbitt will break apart when it lets go of its backing, tinned, or peened. When a bearing fails, IT DOESN'T know if is thick or thin. If the bad bearing hasn't run to long, and destroyed all the evidence, you can tell on the shell what has happened to adhesion.

(QUOTE)I also don't believe there's never been a bad bearing in 42 years ..... he just never heard about it, that's all. Some people won't report anything while others will report the slightest problem.(END QUOTE)

Now, my dear Lar, I can't in all honesty say I can fault you for not believing I haven't had a bad bearing in 42 years, I have heard the guys on the Barn talk about alot of real bad experiences, which is always of Great interest to me. You say some people won't report, I AGREE with that 100%. I think that happens, more then not. The one thing you don't know about my shop, is that for at least 32 years, I had a 6 man shop, "until they started retiring,"counting me, yes, I counted myself. In short, to find a good replacement, just don't work out, spend 6 months training a Guy, and when they can do some things on there own, the next day they come in and say, they will moving closer to ther girl friend in collage. I couldn't blame them, but I think they knew that was a possibility. Anyway Lar, I don't think you can imagine how big a pile of bearings that might be in 42 years. Now 99% of our bearings are rebuilt for other engine rebuilders, and machine shops, always have been. Believe you me Lar, if one of our bearings went bad in there engines, I WOULD HERE FROM THEM, THEY WOULD NOT LET YOU GET BUY WITHOUT THAT, as their customer would be on them to fix it. There would be no money in it for the engine builder, or me, we do stand behind what we make, but even at that, I bet that would be the last time he used us, so thats why we try to build them to last, weather spun, or Jig poured. We sold Spun Model T rods, cam bearings, and ball caps, Model A rods, and Model B rods, to most of the major parts houses, until the rebuilding cost had a to large of margin between, our spun rods, and jig poured rods, so we don't do them anymore, except for our own engines.

(QUOTE)Kohnke is not the only person with engine experience. END QUOTE) Yes, Mr. Lar, I agree with that a 100%, in fact, of all the guys that are on the barn, that are engine builders, I am probably in THE BOTTOM 10% but it will never be about thick babbitt. Now, I shouldn't have to come back here again, unless Ryan really hurts me bad or you use one of your ALLOW ME TO TONE THINGS A BIT STATEMENTS.

I am going to TRY to post some pictures of a set of 1926 CHEVY 4 rods, for a shop in New York State. They are .060 under size, way to thick of babbitt. Love Ya Lar, Herm.

 

[30Tudor]

Larry and Herm - I really respect what both of you guys have to say and I think its OK that you have differences in opinions. However, getting personal just takes away from the whole spirit of this place which I believe is a forum for sharing ideas and learning from each other. I'm just worried that you guys are going to end up in a fight to the death and then unfortunately the rest of us will be deprived of your excellent contributions in the future.

 

[Larry Brumfield]

Larry and Herm - I really respect what both of you guys have to say and I think its OK that you have differences in opinions. However, getting personal just takes away from the whole spirit of this place which I believe is a forum for sharing ideas and learning from each other. I'm just worried that you guys are going to end up in a fight to the death and then unfortunately the rest of us will be deprived of your excellent contributions in the future.

Thanks for your concern but neither one of us is as excited as it may appear.

Larry B.

 

[PC/SR]

Herm: Not to distract from the debate, which I follow with interest, I am impressed that the oil grooves in the Chev rods are really similiar to the MOdel A rod grooves. Were they that way stock, or is that cut a later improvement? Also note two spurt holes in the big end. Was there a dipper arrangement? It looks like there may be a hole in the cap next to the center protrusion down from the cap and was that a "dipper?" I can't really tell from the photos. I wonder that if the Chev and Ford engineers came up with basically the same groove design it may be the best design, and improper grooving on rebuilds may be a cause of failure. Thanks Pat

 

[Kohnke Rebabbitting]

Herm: Not to distract from the debate, which I follow with interest, I am impressed that the oil grooves in the Chev rods are really similiar to the MOdel A rod grooves. Were they that way stock, or is that cut a later improvement? Also note two spurt holes in the big end. Was there a dipper arrangement? It looks like there may be a hole in the cap next to the center protrusion down from the cap and was that a "dipper?" I can't really tell from the photos. I wonder that if the Chev and Ford engineers came up with basically the same groove design it may be the best design, and improper grooving on rebuilds may be a cause of failure. Thanks Pat

Yo Pat, the Chevy rods didn't start putting in X groves, untill the the first Chevy 6 cylinder in 1929. All of the Chevy 4 Cylinders were smooth inside. The holes that were drilled in the web of the rod, on both sides, were just about 3/8 between holes, and FORD drilled their web holes to intersect in to the same hole. Now on the rods I posted, there is a oil hole in the cap that has, like you said, a protrusion, or, for lack of a better word "dipper" in front of it, that when it hits the oil, it splashs it in the hole, I Hope, although it is not a REAL dipper in the metal on the cap. There were many makes that had that design. I put in the X groves in all rods that didn't have groves, if the rod is made like that, as there is no design better, as 1929 Chevys had them with tin dippers clear up to 1953 in the 216 Chevy sixs, although the 216's have a different oil well, and oil grove design. I will post a picture of our spun poured Model T rods, that we used to build, like Model A's. Thanks Pat, Herm.

 

[Mike V. Florida]

How to you pour babbitt and play the banjo at the same time?

 

[James Rogers]

Herm: Not to distract from the debate, which I follow with interest, I am impressed that the oil grooves in the Chev rods are really similiar to the MOdel A rod grooves. Were they that way stock, or is that cut a later improvement? Also note two spurt holes in the big end. Was there a dipper arrangement? It looks like there may be a hole in the cap next to the center protrusion down from the cap and was that a "dipper?" I can't really tell from the photos. I wonder that if the Chev and Ford engineers came up with basically the same groove design it may be the best design, and improper grooving on rebuilds may be a cause of failure. Thanks Pat

Pat, I just finished a 28 Chevy rebuild and the stock rods were not grooved. The rods were smooth with only holes to allow oil migration and were only worn enough to need reconditioned. The dipper on the cap is solid and was for splash ing oil but has a hole slightly in front of it. The Chev engine has 4 small oiler tubes directed from the oil pump to spray oil directly at the holes in the rod caps. It must work since the miles were high on this car and wear was low but it still needed rebuilt.

 

[Kohnke Rebabbitting]

How to you pour babbitt and play the banjo at the same time?

A 5 string banjo only plays happy music, even when I play, and it makes you pour faster, and I have always been able to multitask. thanks Herm.

 

[PC/SR]

James and Herm: Thanks for the info. I had no idea Chevy had the oil spray tubes that early. They were in my Mother's 53 Chev, but I could never get #2rod right. The shims were long gone and I would file the cap but the knock would always come back, probably because by that time the cap was shaped more like a football than a circular bearing. One day the crankshaft broke right in two behind #2. Never heard of that before or since. Pops was not happy. Jim Brierely told me that he once saw an A (or maybe B) block with about a mile of tubing set up for tubes to spray oil directly at the dippers. Lots of work to do that and I doubt it would be much of an improvement except maybe at high speed when the dipper troughs might run out of oil but at that point a full pressure system would be the way to go.
PS to Mike V Florida: OK, I'll bite. HOw do you pour babbitt and play the banjo at the same time?

 

[George Miller]

I have a comment about thick babbitt. I'm not taking sides with and one, just what I think. My experience with thick babbitt is not good. It is inclined to pound out, flake, crack. Will it work for a stock engine running at 45 and under Probably. would it run as long as thin babbitt I do not think so. My experience as a mechanic and a full time machinist in the hydraulic business, I say it will not hold up as well.

 

[Dave in MN]

Can you run an A wide open? Yes you can...sometime!

Good question 29RPU. Great activity on this thread.

I also think that keeping up with the traffic in the slow lane is safer than holding up traffic. I regularly run 60-65 in the slow lane if needed with my "A". I know from experience you need modifications to your engine, drive train and brakes to run at that speed for any extended period of time. A conventional engine will obtain that speed (60-70 mph) if you have adequate carburetion and proper advance on the dizzy. The problem is the engine won't last...the ability of the exhaust valves to handle the extreme heat from an extended high speed run is the problem I encountered with my stock engine. Burned up two exhaust valves thinking I could run at that speed.

After the experience with two burned exhaust valves I looked for ideas that would allow me to run at the high speeds but keep the engine together. When I rebuilt an engine for myself 9 years and 48,000 miles ago, I inserted the mains and rods, installed exhaust valve rotators, .125 over pistons (modern Chev 283 style...heaven forbid!), counterweighted the crank, lightened the flywheel and balanced and weighed everything. Installed a touring cam, Brumfield 5.9 head, electronic ignition, oversize intake valves, enlarged the intake manifold to "B" sizes. I run a standard performance tuned "A" Zenith carb. Installed the largest cooling capacity Brassworks pressurized radiator with an overflow tank I could fit in front of the fan. Changed to a V-8 pressure plate, added a Mitchell 26% overdrive to keep the rpms down, installed cast iron brake drums on all four. I have driven this engine and drive train hard for a lot of the 48,000 miles and have never had the pan off the engine. Replaced the head gasket twice in that many miles...once was just to check for carbon in the combustion chambers. If I have a head wind, I often have the pedal to the floor to keep up with the right lane on the freeway. I think my experience proves to me that these engine blocks can only handle the load demands of reaching the higher speeds if extensively modified and by holding the engine rpms down.

For what it's worth: Just once, I held the car steady at 70 to 72 mph for about 180 miles on an interstate with a small tail wind. (That was the speed those crazy Michigan people and matching crazy Minnesota guy were driving in the right lane on that day. I occasionally had to pass someone going slower...quite a few double take looks as I went by in my open air Phaeton...it was kind of funny to watch their looks of surprise. ) During this run, with the tail wind, the pedal was not to the floor so it probably can't be considered flat out wide open. I would have gone longer but I had to slow down and stop for gas.... The engine held together with the coolant temp staying just below 180 degrees.

Going fast is not for everybody...most say it defeats the purpose of owning a Model A...I agree. I like 25 to 45 mph best. Love the tours with our local Club...but we live 30 to 45 miles south of most of the starting points of the tours. Freeway travel is often our best option for part of our travel on tour day.

I.M.O. If you are going to go fast...know the limits of your car...Please keep a safe distance between you and the guy in front of you. If you reguarly drive in the right lane of the freeway, keep an ever watchful eye on the activity at the on and off ramps. People entering and exiting the freeway are probably your greatest danger.

Keep your brakes and steering tuned to the best they can be!
Good day!
Dave in MN

 

[George Miller]

Dave it sounds like you got it right.