Adjusting crank & rod caps

R

Ron/IA

Well-known member
This winter I am going to drain the oil, and remove the side cover and oil pan to adjust the rod and crank caps on my engine. I do not know if this engine has been checked in its history, but I guess I will find out when I dig into it.

Now for my question - Has anyone used the aluminum foil method instead of plasti-gauge? I am looking for the pros and cons to this method, or if there are any tricks anyone has discovered using this method.

I have instructions describing how to do it. It is pretty straight forward, but seems to be labor intensive as you check each rod or crank cap one at a time.

If you want, I can go into more details about this method, but for now I am just looking for anyone who has used it and been successful.
 
There are different ways to do a job. All you are trying to accomplish is having the bearing tight enough to not destroy itself and keep the oil in. I use plastigauge and don't know why not to. I can adjust rod and main bearings by feel and don't need any gauge material, that is because I was shown by a good old-fashioned mechanic.
 
J - I have a few reasons (which may or may not be valid) for wanting to use the foil method. Some are: no experience with plasti-gauge, winter time (unheated shop), and flexibility of the crank w/flywheel. These are things, over time, that I have come to understand in discussions (both forum and face to face).

I wish I had the "touch or feel" you speak of; I might become a really popular club member.
 
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J Franklin stated it best, plasti-gage is the tried and proven way to adjust bearings, it also the quickest and easiest way and doesnt require any specialised tools, dont over engineer a simple job
 
Ron, I have used the foil method and also use plasti-gauge. I use the foil method when the motor is in the car since it is easier than using a jack to take the flywheel pressure off the rear main to prevent a false reading. I use plasti-gauge when the motor is out of the car and I can roll it pan side up. This is the easiest way if you can remove the motor and work on it outside the car.
 
Ford1 - I agree that plasti-qauge would be the quickest (even though I have never used the stuff). However, as James stated, flywheel weight could produce a false reading (I am concurring because I have seen the same statement elswhere), and I am not planning to remove the engine (as yet, I might change my mind).

James - when you used this method, what did you use for aluminum foil?
 
Ron/IA said:
Ford1 - I agree that plasti-qauge would be the quickest (even though I have never used the stuff). However, as James stated, flywheel weight could produce a false reading (I am concurring because I have seen the same statement elswhere), and I am not planning to remove the engine (as yet, I might change my mind).

James - when you used this method, what did you use for aluminum foil?
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I use Alcoa foil and measured it before I started. Heavy Duty foil is normally .001 thick so I use a 1" X 2 1/2" piece and fold it across the 1" side to make a piece 1" X 1 1/4" piece. You can use a piece of 1" X 1 1/2" piece of brass shim stock .002 thick. This can be purchased at most bolt and nut suppliers or MSC.
 
James - Thanks. I have read the foil should be .002", and have seen stated that "heavy duty" foil is .002". It sounds like I better measure twice before assuming, or excuse me, using. I like the idea of the .002" brass shim stock.
 
Whatever method you use, just be sure you give the crankshaft a full rotation to make sure that there are no tight spots. Some folks forget that the shaft wears in an oval shape. If your clearance is adjusted on a flat spot, it may be too tight on a high spot.
 
Just spin the crank after you check it,not with the foil or plastigage in it.I did talk to a man that told me the plastigage was smearing,and he could not get a reading on it.He was turning the crank,checking for a bind,but nobody had told him to take out the plastigage and oil the crank first.
 
I have used both foil & plastigauge methods more than once.

strongly recommend the foil method regardless of whether the engine is in or out of the car.

no scientific evidence to back this opinion, but the foil is easier and seems intuitively to be more accurate.
 
I did both.

Plastigauge to .0015, then ran 2 thicknesses of foil-crank wouldn't turn. Ran 1 thickness of foil and the crank turned. Smeared #3 down with engine rebuilder's oil, and now she runs without a clank!

Measure twice, cut once.
 
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