Taking up the mains and rods

Colorado Greg

Colorado Greg

Senior Member
I've got about 2K miles on it now and I think I can hear a faint rod knock under a no load condition. I also have a pretty good oil leak at the rear main. I'm just wondering what the best/easiest way to get this accomplished.

Should I adjust everything with the engine in the car or pull the engine and do it on an engine stand?

The local Model A club suggestes that I do it with the engine in the car and to use the newspaper method.

Let me know your thoughts on this please!
 
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Newspaper method;

Cut newspaper into approx 1" strip, soak in oil, verify thickness with caliper, lay it across the bearing, tighten bearing,
Does crank turn easily?
yes, remove shim and recheck
no - just right as long as crank turns easily w/o paper
proceed until all bearings are gone though doing one at a time.

Pretty much like the foil method but using oiled paper.
 
It can be done in the car but is will be a lot harder to do it that way. If you take the engine out and do the adjustment you can look at other things like the valves and the timing gear and the clutch. Remember if you fined a problem in the lower end you will be pulling the engine out any how. News paper in not the way to check the clearance, I would use two peaces of brass .001 thick squares and when the crank locks up with .002 brass squares and will move with only .001 you have a good adjustment. Use this on both the rods and mains. Good luck
 
Colorado Greg said:
Newspaper method;

Cut newspaper into approx 1" strip, soak in oil, verify thickness with caliper, lay it across the bearing, tighten bearing,
Does crank turn easily?
yes, remove shim and recheck
no - just right as long as crank turns easily w/o paper
proceed until all bearings are gone though doing one at a time.

Pretty much like the foil method but using oiled paper.
Click to expand...

Use aluminum foil no soaking, no verifying the rest the same
 
I have heard of the aluminum foil interference method and done it, but never the oiled newspaper method. Let us know how it turns out. The newspaper must get torn up when the crank is rotated. I wonder if some of it could get into the oil holes.
Rusty Nelson
 
Kohnke Rebabbitting said:
Greg, so how much clearance do you end up with on your Newspaper method, and is that what was used in the first 2000 miles.Herm.
Click to expand...

Herm, I'm being told the the newspaper is .0017 or so, thus the step to measure. I've never done this before but it seems pretty straight forward.

I was all set to pull the engine and do this with the foil method until I spoke with the engine guru for the Model A Club. It sure seems like ALOT of trips from the floor to the crank doing it in the car.

I have no idea how it was originally done. The engine was re-babbitted in 1972 by a well known local guy and only had about 500 miles on it when I got it from my Father in April 2010. When I first got it running I didn't notice a rod knock but now I'm pretty sure that I hear it.
 
Greg,
If you are also chasing a rear main leak...it would be easier to fix on a stand. The process of obtaining a rear main that isn't a gusher is just a matter of blocking the path of the oil at all the possible locations the oil can leak. It is much easier to accomplish when you have full access to the bottom. When you take the engine apart, carefully examine the contact areas of the pan and rear cap for "oil slicks" as they indicate the path of the leak.
I like splitting it at the bellhousing and flywheel housing when removing an engine. If you have not done it before, ask for help from a friend while removing and replacing.
Good Day!
Dave in MN
 
Oil leaks can be tricky to stop. Get the engine out for sure and have someone who works on engines help you with it that knows. I would still use brass shim stock and cut it into 3/4 by 3/4 squares to check the clearance. there are some other things u can do also that one of your local builders should know. If you have any questions you can PM me and I will walk you through them.
 
I would prefer to do the checks out on an engine stand, which in the long run is much easier than under the vehicle, either laying on the floor, or even on a hoist.
If you still plan on working on the engine from underneath, fabricate a bracket, using a length of 3/4" angle iron, to go across the rear crank web, from one oil pan bolt to the other side oil pan bolt. You want to make sure you support the crank solid against the block side of the rear main bearing, otherwise you will obtain eronious readings. You will have to grind a 2" grouve off one side of the angle iron, to obtain enough clearance to remove the main. I prefer to use .001" brass shim stock or aluminum foil. Both work good. It is always good to have help from other club members, especially if a sandwich and a beverage or two might be found.
 
Colorado Greg said:
I've got about 2K miles on it now and I think I can hear a faint rod knock under a no load condition...
Click to expand...
I had this same thing happen - at about the same mileage. Was only a faint knock until all hell broke loose. Turns out that the babbitt on #1 rod had disintegrated. I firmly believe that had I "heeded the warning" that the engine was trying to tell me and adjusted the shims, I could have saved a whole bunch of grief and down time.

BTW, did all the work in the car (with the help of a friend), using plastigage to set the tollerances. Of course while we were at it, checked/adjusted all the other rods and mains as well.
 
If you're going to try this with the engine "in-car", get set-up in the garage with plenty of space to roll in & out form under the car, and plan on it taking a while... probably more than an evening, maybe a whole Saturday ?

I once adjusted the rods on my '50 Chevy Fleetline, and it seemed like it took forever.

I need to do this to my own '28.
 
Well I'm slow, I've worked two afternoons and have only gotten the mains done. I'm telling myself that the rods will be easier. :-)
 
After further discussion with some Model A experts today, I'm going to pull the engine and do this on an engine stand using plastiguage. I'm concerned about false readings doing it with the engine in the car. I'm going to pull the engine and ****** as one piece then seperate after it's out of the car. It will be alot easier to get the trans lined up when installing and the trans doesn't weigh very much at all.

I have alot of experience with R&R of engines etc..., just not a model A. Everything seems a little different on these old cars. It should be easier to pull this engine compared to a Chrysler 440 in a '48 Anglia Super Gasser, that's a tight fit.

I'll probably be doing most of the work by myself as my friends don't like my food or drinks, lol. Hopefull I can get this done this weekend and will report back.
 
I got this all accomplished with great results!

I ended up using the plastiguage and everything turned out good except for the rear main. When I got the clearance to .0015, the crank was very hard to turn. (I actually broke my crank pulley trying to turn the crank. It was a weird pulley that was two pieces pressed together. I showed it to some A folks and they hadn't seen one like it. It was also a little smaller in diameter then the replacement I got.) I ended up putting one shim back into the rear main to allow the crank to turn.

Everything inside the engine was in good shape but I was suprised to see some split-skirt pistons in it. I had never seen a piston like this before but apparently they were used w/o problems. Valves were adjusted correctly and the pan was clean.

My oil leak problem was either the gasket between the block and flywheel housing or the rear seal had a fiber gasket in the outmost groove and it was plugging part of the hole for the rear main drain. The flywheel gasket was torn and I could see an oil path in the gasket that remained.

The no load knock that I had has also disappeared. When I removed the bell housing there were no shims so I dialed in the bell housing. It seems she has less vibration now and the sweet spot went from 45mph to 50mph. Just seems alot smooooother now.

I got it all painted real nice and installed. I have about 200 miles on it now and no oil leak so far. If this keeps up I'll have to change my signature. :)

Thanks for all of the advice!
 

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