To Balance or Not to Balance
 

Good afternoon, friends. I am a new owner of an early '30 coupe.

I am blessed enough to have in my garage a Mitchell O/D and SynchroMesh Tranny. Saved my money for 3 years for a project, and my new-to-me Model A is a perfect use of these funds.

My car runs great, starts easy, idles well, good brakes, great condition, runs very cool (thanks to ya'll's radiator flush), basically has no issues. I got lucky, I know. I bought it from a widow out of a barn, not driven for many years. I received lots of good advice from the FordBarn to get her tip-top.

The engine was rebuilt in the past; the cylinders are 0.060" overbored. I noticed this when I changed the head to a 5.5:1 when the head gasket failed -- all ya'll's recommendations.

Differential is good and quiet, except it leaks 1 oz of fluid every two weeks through the driver's side banjo gasket (not the bolts).

I tried to get my wife and three grown boys interested in Model A's, but the double clutching and performance here in the Smoky Mountains discouraged them. The SM Trans and O/D hopefully can bring in new, young interest into our passion.

So, this Autumn, I am pulling the rear-end, torque tube, transmission, and bell housing to install everything. I will be changing the FW pilot bearing, throwout bearing, and clutch plate. Should I pull the flywheel to deglaze and balance it to the adjusted pressure plate? My local machine shop said they can do it the same day I bring it to them.

After the recent excellent video on YT from "I am the warranty" guy I feel encouraged. I asked him in the comments and he said "if she runs good and is not vibrating do not pull the flywheel". My Model A club is split when voting. Either "don't fix what ain't broke" or "don't go looking for things to fix on an A, you will always find something" to "if you do not do it now, you will never have the chance again, because engine and power train will all be modernized".

I have no idea if any of the previous owners did this or when the engine was rebuilt decades ago.

As little as I drive her, with a rebuilt engine running well, and essentially a new power train once I finish the install, the flywheel should never see the light of day again.

What is the consensus of the FordBarn? Do I pull the flywheel and deglaze and balance it or not? Or, should I do what Saturday's video suggested.

Does the car and engine vibrate == yes, a little, but that could be 94 years or it could be normal for this car? Is my flywheel causing any problems == noone in my club seems to think so?

Thanks in advance,

Diastole in the Smokies

Re: To Balance or Not to Balance
 

It is normal for a stock Model A engine to vibrate a little because of the way the engine was designed. Regarding balancing the flywheel: Since you have oversize pistons, someone was in there at some time. They likely balanced the flywheel and clutch pressure plate. You will find holes drilled in the flywheel at odd places (likely at the outside diameter) if it was balanced. If they did a good job they balanced the pressure plate too or balanced the flywheel and pressure plate as a unit. If you take the pressure plate off to change out the clutch plate, match mark the pressure plate to the flywheel so that it goes back together in the same location.

Buy the plastic alignment tool that aligns the clutch plate with the flywheel. Otherwise you will never get the transmission to engage with the clutch plate. See https://www.snydersantiqueauto.com/p...9061&cat=41664

You may find radial cracks in the flywheel if it got hot at some time. These do no harm and can stay there. Unless the flywheel is deeply scored I would leave it alone. If you do remove the flywheel match mark the flywheel to the crankshaft so that goes back in the same location. After you reinstall the flywheel, check the runout at the clutch surface. It should be less that 0.002 inch.

Yes, it is a good idea to replace the throwout bearing and the pilot bearing. Just because they are hard to get to if they go bad in a short time after the clutch job.

Re: To Balance or Not to Balance
 

Just because there are balance divots drilled into the flywheel doesn't mean that the flywheel was balanced to that crank in the reground configuration. The flywheel will install on the crank in two positions 180 degrees apart. Having said that, most folks do NOT rebalance when their crank is reground.

NK recommends using the plastic pilot tool when reassembling. I have found the plastic tool to be unreliable (Model As and other cars like old VWs). Since you have a new Mitchell tranny, suggest that you pull the input shaft from your old tranny and use that as the disk alignment tool. If you've already shipped your old tranny, ask around and get one from a club member. They are readily available.

And I almost always pull the flywheel and have it resurfaced when I do a clutch job. As long as you are that far in, a bit more doesn't hurt. Schlepping around that 60-lb flywheel while the engine is still in the car is a bit of a challenge, though.

(A hint - if you guys order a tranny direct from Mitchell and have it shipped, ask Steve to throw in an old input shaft if he has one lying around. That will be your "forever" disk alignment tool. He doesn't use them in his rebuilds.)

Re: To Balance or Not to Balance
 

If you like how the engine feels why change it. things may have already been balanced on the last rebuild.

Re: To Balance or Not to Balance
 

I wouldnt touch a thing and drive the car. you state that the car gets very little use.


I will bet you dollars to donuts that your family will still not be interested, when you do the reinstall. sounds like you enjoy "projects" which is fine.


find what your family does enjoy and spend time with them doing that, while you enjoy your A on your own. that is my experience.

Re: To Balance or Not to Balance
 

I enjoy driving and working on my Model A. But my wife does not. However, she enjoys the tours in the Blue Ridge Mountains and the companionship that comes along with that. So I drive the Model A to the tour location and she follows in the Toyota. Then we together enjoy the meals and time with fellow club members while driving in the Model A's.

So, bottom line, find an activity that involves the Model A that your family can enjoy together.

Re: To Balance or Not to Balance
 

Since you're going to be taking it apart, it would be a great idea to have it done.
that 63 pound flywheel makes a big difference to the engine when it's balanced as a unit with the pressure plate.

Seems everyone says the car runs good but truly runs better when they're balanced.

Re: To Balance or Not to Balance
 

On longer tours my wife typically flies to about the halfway point and joins me there for the rest of the tour. Reasonable compromise for us, having a navigator on board sure does make things easier for me.

NK, can your copilot drive the car?