How to surface a flywheel

[BogusSVO]

How To Resurface a Flywheel



I need to replace the clutch, and I want a “new” clutch surface on my flywheel so the clutch will operate problem free.

The first step is to have the flywheel cleaned of oil , grease and grime.
This flywheel is in decent shape minimal warp and few hot spots

I found my Ford Dark Blue Spray Paint!!

Next is to mount the flywheel to the machine
Move the flywheel under the grinding stone, and touch off….

Each pass is only .002 -.003 deep per cut

See the sparks?

Now that we have a good surface for the clutch disc to mate too…

One last thing to do is to knock in the pressure plate alignment pins

All done…

 

[slowmkviii]

cool
are the hot spots that deep that you need to take off so much stock
also just curious do you measure parallelism and flatness and circular flatness after your are done just wondering how accurate you need to be

 

[Frogman]

Why are you posting this in two different subforums?

 

[BogusSVO]

cool
are the hot spots that deep that you need to take off so much stock
also just curious do you measure parallelism and flatness and circular flatness after your are done just wondering how accurate you need to be

Normally, there is not much to be removed from the face of the flywheel, due to hot spotting, I would say with as many flywheels that I have resurfaced, 80% or so had .010 or less removed. Alot of that has to do with how long the clutch was slipping.

There is a "cupping" that happens to most flywheels, which is caused from the pressure plate pulling on the outer edges of the flywheel, I feel this is due from heat build up, even under normal driving, and the diffrent expantion rate of the steel pressure plate and the cast iron flywheel.

Frogman, Sorry I did not relize that I did.

When I resurface a flywheel, I try my best to keep less than .002 flatness from the outer edge to the inner edge, and the runout around the flywheel to .002 also.

The way most flywheels are set up to be ground is a machined adapter cone fits into the crank mounting flange, and the surface is indexed off the flange.

What is important to keep track of is the amount surfaced from the face, This will cause clutch engagement problems, on Hyd clutch set ups, after the flywheel has been surfaced appox .020-.030, the rod on the slave cylinder may not have the movement needed to operate the clutch properly, due to the reason the flywheel has moved further from the slave. That is an easy fix, shims are made to be inserted between the flywheel and crank.

 

[kustomizingkid]

Why is this person posting all this on LVC?

 

[slowmkviii]

bogussvo thanks for the reply just wanted to know how wide the tolerances were on a flywheel in case I do one for fun at work in the future and those numbers should be easy to hit

 

[BogusSVO]

Why is this person posting all this on LVC?

I have been doing automotive macine work since 1992. I have joined several fourms over the years looking for info on diffrent engines.

I post this type of stuff for the people out there that do not know what happens with there parts when they drop them off at the machine shop.


SlowMKviii... best of luck, it is a relitive simple thing to do, the surface finish is about the most important, leave it to rough and you will chew through a disk is a short amount of time, too smooth and you can end up glazing the disk/flywheel, that happens when the disk over heats and resin in the disc material "boils out" then re hardens on the disc face.