Bearing clearance. Foil method

Maclab58

Maclab58

Well-known member
Can anyone enlighten me on how to set bearing clearances using foil? I have Seen the DVD from the Orange county model A club and I would like some more details.

Thanks, Jim.
 
I have done the foil method on two model A engines. I works pretty well, but is quite time consuming. First you add enough shims on the mains until the crankshaft will turn easily. Leave the other mains loose while you are adjusting the main you are work on. Then cut 1" by 1" squares from some aluminum foil. Cheap aluminum foil is close to .00075" thick, but you need to measure it with a good micrometer. You usually need two thicknesses of the foil, so I usually cut a 1" by 2" foil piece and double it over to keep them together. Next put the foil in between the crankshaft and the main cap. I have heard it is best to start with the center main, but I am not sure it makes any difference. Torque the main bearing bolts to 70# or 80# (whatever the final torque you want). Try to turn the crankshaft by hand. It it turns easy or at all remove the bearing cap and remove some shims and do the same thing again. Once you can't turn the crankshaft by hand, add a shim(s) and see if it turns by hand. BTW, the other bearings should be loose so they don't contribute much drag at all. The idea is to have the crankshaft lock up with one few shims and adding one or more back until the crankshaft will turn with a little effort. This should allow about .0015 bearing clearance that is recommended. Once you have one main adjusted, move to another bearing and do the same thing. Loosen the bearing you just adjusted so it wont cause much drag. When all the mains are adjusted, go to the rods and do the same thing as the mains. I have heard that the foil should not be used more than once, but can't see why not. Once you do a few bearings, you can kind of estimate the shims need and reduce the assembly/disassemble time to do each bearing. I hope this is clear.
Rusty Nelson
 
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Yes, when the bearings are adjusted the foil is removed and the crankshaft or rods should turn with a little effort.
Rusty Nelson
 
Does anyone remember the gentleman who introduced most folks here to the "foil method"??

HINT: He owned the Miracle Motor Company, ..their motto "If it's a good 'ne, well then it's a 'Miracle'!!" :D

.
 
BRENT in 10-uh-C said:
Does anyone remember the gentleman who introduced most folks here to the "foil method"??

HINT: He owned the Miracle Motor Company, ..their motto "If it's a good 'ne, well then it's a 'Miracle'!!" :D

.
Click to expand...
BRENT. mike flannigan, the model a fool he called himself. I believe he was from Phoenix AZ . Sure was fun seeing what he was going to write about, He must have been fun to be around. He did fluff up alot of feathers on some of the guys. He called his wife THE BIG BLONDE. have fun modelAtony Lafayette,LA
 
wrndln said:
I have done the foil method on two model A engines. It works pretty well, but is quite time consuming. First you remove all the shims on the mains (or most of them until the crankshaft will still turn easily. Then cut 1" by 1" squares from some aluminum foil. Cheap aluminum foil is close to .00075" think, but you need to measure it with a good micrometer. You usually need two thicknesses of the foil, so I usually cut a 1" by 2" foil piece and double it over to keep them together. Next put the foil in between the crankshaft and the main cap. I have heard it is best to start with the center main, but I am not sure it makes any difference. torque the main bearing bolt to 70# or 80# (whatever the final torque you want). Try to turn the crankshaft by hand. If it turns easy or at all remove the bearing cap and insert(remove) some more shims to do the same thing again. Once you can't turn the crankshaft by hand, remove a shim(the foil) and see if it turns by hand. BTW, the other bearings should be loose so they don't contribute much drag at all. The idea is to have the crankshaft lock up with one (piece of foil)shim too many and by removing it, the crankshaft will turn with a little effort. This should allow about .0015 bearing clearance that is recommended. Once you have one main adjusted, move to another bearing and do the same thing. Loosen the bearing you just adjusted so it wont cause much drag. When all the mains are adjusted, go to the rods and do the same thing as the mains. I have heard that the foil should not be used more than once, but can't see why not. Once you do a few bearings, you can kind of estimate the shims need and reduce the assembly/disassemble time to do each bearing. I hope this is clear.
Rusty Nelson
Click to expand...

Somthing is wrong here. You are calling both the shims and the foil, shims.
I think I get the gist of it, but haven't you made a mistake in nomenclature here?
Are my changes missing the point or am I correct?
 
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Flannigan! Memories of Shelly's Fordbarn. I have one of his "miracle" B engines. I sold the boat and chain it was attached to, so it has dried out and no longer gets used.
 
Russ/40,
Boy did I mess up the description I wrote. I tried to correct the many errors in it. Sorry. Maybe you could proof it again and maybe I still have an error or two in the description. I should have reread it a couple times again before I posted it.
Rusty Nelson
 
MikeK said:
Flannigan! Memories of Shelly's Fordbarn. I have one of his "miracle" B engines. I sold the boat and chain it was attached to, so it has dried out and no longer gets used.
Click to expand...

I received one of his last engines (A) had it looked at and found a whole lot wrong with it. He used "modern" seals ant it leaks like a sieve.

I have used the foil method with GREAT success several times. Quick, easy, and fool proof.
 
wrndln said:
Russ/40,
Boy did I mess up the description I wrote. I tried to correct the many errors in it. Sorry. Maybe you could proof it again and maybe I still have an error or two in the description. I should have reread it a couple times again before I posted it.
Rusty Nelson
Click to expand...

Rusty, gotta give you credit for your effort. Its hard to put something like that into print. If the blue text is deleted, and the red added, I think it all comes together. Thanks for getting it down for others.
 
Does anyone know, is Mike Flanagan still alive? I thought he was pretty sick in those last days of his posts. He sure could write great stories!!
 
I'm pretty sure I have seen the foil / paper shim "lock-up" method of adjusting bearings listed in MoToR's and / or Chilton's shop manuals of the 1940's and '50's... when Buick, Chevy, and Hudson eights were still running poured bearings.

It is a reliable method... just gotta remember to pull the foil / paper when you're done.

;)
 
BRENT in 10-uh-C said:
Does anyone know, is Mike Flanagan still alive? I thought he was pretty sick in those last days of his posts. He sure could write great stories!!
Click to expand...

Flanagan sure took a lot of credit on here, unfortunately for him, he didn't invent the foil method as he claimed.

He's still alive, he's gone a little crazy (as we saw here), and is living out his time in a remote AZ town where he can do no harm. He never made many friends in any of his endeavors.
 
azmodela said:
Flanagan sure took a lot of credit on here, unfortunately for him, he didn't invent the foil method as he claimed.

He's still alive, he's gone a little crazy (as we saw here), and is living out his time in a remote AZ town where he can do no harm. He never made many friends in any of his endeavors.
Click to expand...

Your last sentence seems quite plausible!! ;) Seems I also recall him telling about his bullriding days, ...and hearing someone tell that the "bull" he was riding was not the same four-legged animal we were thinking! :D

,
 
If you didn't take him seriously he was quite entertaining.
But mostly, to me at least, he came across as just another internet manure merchant with a mouth full of samples.
 
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