Excess runout on flywheel
 

Good afternoon all,
Today I mounted a dial indicator to the flywheel housing to check the run out of the flywheel.
It is .017 and Les Andrews states .005 is max run out.
What are the implications of this condition?
I've put 15,000 miles on the car over the last six years but took it apart to stop the transmission from leaking and try to determine the cause of clutch chatter.
Please let me know if you've experienced this and if you corrected it.
Thank you for your help.
Al

Re: Excess runout on flywheel
 

Are there the horseshoe shims on the two bolt locations at the top like there is suppose to be. Where is the max and min distances on the housing (top, bottom, left or right side)?
Rusty Nelson

Re: Excess runout on flywheel
 

When I read the question, I think the crankshaft and flywheel has a total movement front to back .017". If this is so then there is a bronze rear main thrust washer, available from Berts and Snyders part # A-6336.
I've never used one but I need one for my engine. Hope someone with installation experience will join respond.
carry on

Re: Excess runout on flywheel
 

If the engine is still in the car you need to be sure the crank is not moving back and forth.
We need to all be on the same page. Al is saying flywheel run out, Rusty is talking about flywheel housing run out, and Nick is talking about end play.:rolleyes:

Bob

Re: Excess runout on flywheel
 

Good guidance Bob. The engine is still in the car and the dial indicator is on the housing but is the crank moving back and forth? I have to determine it's not and that it really is rubout I'm seeing and not crank movement. I didn't think about that.

Re: Excess runout on flywheel
 

Runout is wobble of a part, as opposed to running "True". with out wobble. Bob C gets it, Is the FW running diametrically out of true? Or is it wobbling? If it's wobbling there is probably something (Chip, flake, etc) between the FW and the crankshaft. If it's running out of true, then your rear main bearing must be looked at. The crank has two axis. This is unlikely. I would take the FW off the end of the crank and make sure nothing has gotten between them.
Terry

Re: Excess runout on flywheel
 

Al,

I just went through this issue with my 1930. However, there was a paper published in the Restorers Journal addressing the issue. The author states the motor should be out of the car on an engine stand turned upside down with the crankshaft rear flange up. This eliminates the possibility of the crankshaft moving horizontal as may happen if the engine is still in the car as you turn the crankshaft. I placed my dial indicator mag base on the crankshaft flange. The dial indicator touched the flywheel housing. I made sure the two "original" brass shims were in place under the accelerator peddle bracket. All 4 flywheel bolts and the two peddle bracket bolts were torqued down to 55 ft-lbs. I measured the run out only between the oil pan rails along the engine top. Mine was out so I played with the shims only and brought the housing to within 0.006in. I rechecked the measurement the next day to see if there was any movement. All was well. Don't forget to install a new flywheel gasket before you start your measurements. Download that article if you can. It is on the web if you Google the subject.

Wayne

Re: Excess runout on flywheel
 

First dial indicator the crank shaft to the block
Also verify end play
Then mount flywheel and shim only on the top accelerator ears for 3 and 9 o’clock.
Next shim for 6 and 12 o’clock. (On same two ears)
Last clean crank flange and flywheel mounting, and then mount flywheel.
Now dial indicate flywheel, and everything will be square.

Re: Excess runout on flywheel
 

Bob,
Thanks for your sound advice. You hit the nail on the head as the saying goes.
I went back today and setup the dial indicator. We re-did the test and each time it went out of spec we were able to pull the flywheel back. Each time it went back to "0". My friend and I switched places and the results are consistent. I have run out of .001 - .0015.
Very happy camper.
Foot note - When it went out of spec it changed suddenly, not gradually as you would expect run out to do.
Also right on as far as all being on the same page.
Thank you so much for sharing you experience/wisdom with me and all us 'Barners'.
Al Leach

Re: Excess runout on flywheel
 

Went through 6 used flywheel housings to find one that ran out to .005..Horseshoe shims are used if you use a gasket on the flywheel housing.I set mine up with no gasket and no shims,used permatex ultra grey instead. Correct flywheel housing alignment provides smoother shifting and less chance of clutch chatter..as an added bonus sliding the trans into the pilot bearing during assembly is a breeze,with everything aligned it drops right in.

Re: Excess runout on flywheel
 

FWIW
My Model A mentor, presently has 6 cars of his own, and has worked on many others over some 35 years, when I told him I was concerned my runout was between .006 and .014 all the way around, his reply was: I have never paid much attention to that in all the cars I've worked on.

Re: Excess runout on flywheel
 

Its the little things that make a nice driver.A transmission main shaft improperly aligned with the crankshaft will work no doubt.But aligning it makes it better.Take shifting,a spur gear transmission relies on matching shaft speeds to shift smoothly,with the transmission main shaft side loaded by alignment issues it wont spin as smoothly and true as an aligned one..small potatoes? yep,till you drive one with an aligned shaft. A smooth releasing,non binding clutch disc wont chatter and will engage and disengage with less effort.

I doubted dialing in a flywheel housing when I worked on heavy duty trucks till I saw and felt the results..a pretty car is nice, a sweet driving car is better..

Re: Excess runout on flywheel
 

'Just an idea here, because I need to check FW run-out on an engine in the car and am also concerned that end play will interfere with measurement. Why not just depress the clutch to keep the crank all the way forward when taking a dial indicator reading?

Re: Excess runout on flywheel
 

Agreed, on my AA i got it dialed in at about .001 and its a very smooth clutch that just slips then grips. Even with the solid disk style its smooth as can be. Let it out and the engine just bogs a bit, no vibrations no chatter.

Way smoother than the cable clutch on my chevette.

Also if the alignment is off enough it can cause the trans to pop outa gear.

Re: Excess runout on flywheel
 

When checking flywheel run-out the clutch has already been removed. But it is possible to distinguish the difference between run-out and crankshaft axial motion.
Al