flywheel housing alinment

flatheadkev

flatheadkev

Member
I just finished playing with the alinment of my flywheel housing for the third and hopefully last time. I noticed I got the best numbers on my dial indicator when I use one .010" shim under one of the outer mounting ears.
I read several write ups about the procedure, none of them implied their could be an uneven number of shims between these mounting points. I found it made the max. diff. of .006" as opposed to .009", around the upper 180 degrees of the housing. I appreciate any input. :cool:
 
If you got down to 6 thousands, I think you should be content even though you had to put in an uneven number of shims.

I used an uneven number, and still I didn't quite get down to .006. Rather than trying even more flywheel housings and more shim combinations, I stopped at the point just before I would have turned insane from more fiddling !!
 
.006" is OK. Just make sure the crank is always pushed forward when measuing the flywheel cover, so the freeplay doesn't show up as a variation. I like to dial it in while the engine is on the engine stand with the front end pointing down.
 
Sometimes no amount of shiming or fiddling will give good results alining a clutch housing . The problem may be one or more things. I have found many of the housings are warped and even found one engine that the rear machined area was not true to the crankshaft . My method is to put engine on a engine stand with nose down ( as per Tom ) , shim as close as possible ( save these shims ) , set indicator at "0" at the lowest point , write the numbers on the housing showing the high spots . Be sure to double check all numbers. If the alignment is not too far off you may be able to file down the high spots. In extreme cases I have mounted the housing on a rotary table installed on a verticle mill . The housing is shimmed on the rotary table to replicate as close to what it read on the engine. Mill off the high spots . reinstall on engine using same shims as before and check for alignment . You can ignore short low places on housing as they will bridge over. This housing should be kept with this motor as it may or may not fit another engine . If anyone has a simpler method I would like to know it . Good Luck Bubby Sharp in KY
 
is there a publication that details this alignment procedure available ? sounds like it can be a problem ,what happens if you dont do alignment ,
 
I doing mine now , Tom's Tip is a good one that I did not see in the How too. Take a look at :
"How to Restore Your Model A" Volume 4 Page 10, From the Restorer Set


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flatheadkev said:
I just finished playing with the alinment of my flywheel housing for the third and hopefully last time. I noticed I got the best numbers on my dial indicator when I use one .010" shim under one of the outer mounting ears.
I read several write ups about the procedure, none of them implied their could be an uneven number of shims between these mounting points. I found it made the max. diff. of .006" as opposed to .009", around the upper 180 degrees of the housing. I appreciate any input. :cool:
Click to expand...

There is no way that a crank flange can be off that far, as to not be able to level a Model A flywheel housing, to it. If it is off to far to run a flywheel, then you have to fix it. As far as a align bore being align bored off that far as not to be able to align a housing, you would have to start align boring it side ways!! Even If the flange is out .005, from level, and the norm is about .003 to 0, say if one side of the flange is high buy .003, and that is where you clamp your dial, your 0 set is always going to be the same all the 360 degrees. If you clamp to the other side of the flange, you have to re 0, and it will always be the same. I use a Wilson, and clamp to the flywheel flange, and set the dial, and go for level. When you think you got it as close as you can, and its where you want it, let it set for 24 hours, because cast Will change under stress. The flywheel housing, Not able to Warp while bolted up is way off, any, and all cast will Warp, weather it is a block, or flywheel housings, or we would never need remachining work. Herm.
 
Hey guys, what if you don't have a runout guage. Can you get close enough with a straight edge? When I took my housing off, I didn't have any shims at all. Pete
 
Peter J said:
Hey guys, what if you don't have a runout guage. Can you get close enough with a straight edge? When I took my housing off, I didn't have any shims at all. Pete
Click to expand...

Peter, with out a Dial, it is just about impossible to see what is going on. If money is tight some times, I think there places like Harbor Freight, or e-Bay, you can find cheaper units, that work very well. You can find many use's for it other places as well. Many housings did not have shims, and alot of times if they did, the guys that worked on the motors, didn't put them back. Aligning a Flywheel Housing, is to a Model A, as aligning a pan for a ball cap is for a Model T. It takes stress, an bind off of crankshaft, and parts, for less wear, and vibration. Herm
 
DialingInBellhousing.jpg


DialingInCrankshaft.jpg


Here's a picture of the KR Wilson flywheel turner I was lucky enough to get at a swap meet about 8 years ago. The strange this is I bought it from the same guy I bought my first Model A engine from in the early 80's, and it was that engine that got me started in Model A's. As Herm said, you can buy a good dial indicator and magnetic base from Harbor Freight for about $10 each on sale.

The second picture shows me checking flywheel flange runout.
 
I dial indicated the machined part of the block that the flywheel housing mates to and progressively was .004 high on the driver's side. I did this on both the top and bottom of the radius that the housing touches so there wasn't random high spots. It looked like the original machining. As Herm says it was the same attachment point on the crank flange so maybe he has something there about block warping. The .004 is on about a 4+ inch radius so the outer edge of the flywheel housing doesn't stand a chance of under .006 out (where ever that number came from?) even with a perfect housing..............
 
The second picture shows me checking flywheel flange runout.[/QUOTE]


Tom,

How would you correct the above if the edge of the crankshaft was out, the way you are checking in photo #2 ?
You would have to re-pour the mains and align bore to correct?

Should you not be checking the crank machined surface where the flywheel faces up against ?
 
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Tom Wesenburg,

Another question - While checking the "FW housing run out" in photo #1 it appears that the top left side bolt (where the shims often are used) is not screwed down......if so how can you get an accurate reading if it is not tight ?

Also do any of these bolts go through or into a recessed area of the block which would require the use of thread sealer ?

Thanks, Mike
 
Tom,
Went by and raided Harbor Freight for the guage and magnetic rig you suggested (you were right on price wise). I'm going to mark your pics. for reference when I get to the housing adjustment. I had no idea that the housing was machined to those tolerances and so critical.
Thanks Again,
Pete
 
Mikeinnj said:
The second picture shows me checking flywheel flange runout.
Click to expand...


Tom,

How would you correct the above if the edge of the crankshaft was out, the way you are checking in photo #2 ?
You would have to re-pour the mains and align bore to correct?

Should you not be checking the crank machined surface where the flywheel faces up against ?[/QUOTE]

Mike,
I had the top two bolts tight when I made the checks, but just happened to have the bolts loose when I took the picture. It must have been between shim changes.

This is an "AS IS" well used engine I installed to keep my car on the road while I rebuild the original engine. I checked the flywheel side runout in picture 2 just for my own peace of mind. If it was out of spec then the crank would need to be centered off the flywheel flange and the main ground, and the mains repoured and bored to match. Luckily (if the crank was turned) it was done correctly as the runout was 0. I also checked the flywheel mounting face on the crank flange and it was within spec. This is a well used engine and it does have a noise that I don't like and haven't pinned down yet, but I don't think it's going to leave me dead in the road.:eek:
 
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