resurfacing flywheel?

snipped-for-privacy@estaff05.mayfield.hp.com (Ted Johnson) wrote in news:e3oiok$ snipped-for-privacy@estaff05.mayfield.hp.com:

Don't sand it. Get it machined. The machine shop will know what to do. You need that surface flat and true, not roughened. Machining is cheap, less than $50.

Yeah, I would have thought that too, but I guess there's already so much mass that minimum thickness isn't an issue. Unlike brake rotors, a flywheel does double duty: It both smooths out engine vibrations and provides a friction surface. Flywheels also don't have to soak up the kind of heat that brakes do.

Just looked through my factory manual for our '99 Tercel. It too does not give a thickness, just maximum runout, which is given as .031".

"TeGGeR®" wrote in news:Xns97BDF27F3A612tegger@207.14.113.17:

Have never done this myself but have been told that if you have the flywheel machined you may have to use shims to compensate for the amount of surface removed since the clutch does not have an adjustment. When I have done clutch jobs in the past I did NOT use shims but did notice that pedal travel\engagement point was considerably different(longer\higher) with new clutch if the flywheel was resurfaced. This may have been corrected by the use of shims. Just a thought dc

Doncee,

Where exactly would you insert the shims, and why? The clutch cover would bolt to the flywheel & all internal clutch dimensions would be the same - or more accurately restored to original specs.

Cutting 60 thousanths off the flywheel would just move the friction disk that much down the transmission input shaft (closer to the engine)

In any case such a small amount would be trivial compared to friction surface wear, which is the likely reason that you experienced difference in pedal travel and engagement point. Or were you taking them apart for fun, without renewing the friction surface?

-- Mike Harris Austin, TX

It depends on the type if clutch cover. If its the flat type, you dont need shims. If its a step type, and the friction surface has been ground .060, the steps have to be ground .060 as well. Othewise the release bearing has to push further in to release the clutch. Shims can be placed behind the release bearing as necessary.

Stewart DIBBS

If the fly wheel is not burned blue or does not have groove/gouges in it -- it does NOT have to be surfaced/ground/milled. Roughing up with sand paper is just fine. Have done many clutch replacements and only once had to have flywheel milled -- it had heavy gouges and blue burn marks.

Thanks for all the good feedback gentlemen! I do have a few follow-up questions though...

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ One would hope.

Unfortunately I don't have much experience/data with the few machine shops in my area, so I don't know what their competence level is.

It would be "unfortunate" if I were to: o remove flywheel from Tercel o borrow my wife's car to take the Tercel flywheel to the machine shop o later that day, borrow car again to go pick up flywheel o reinstall the flywheel, and put everything else back together

only to find that the flywheel machining job they did is... less than ideal.

Thinking out loud for a sec... maybe I should go ahead and just buy a new 'genuine Toyota' flywheel ($250) and avoid all the downtime and hassle caused by a poorly machined flywheel? That would significantly reduce my DIY savings, but then again I'd still be saving $400+ of labor... I hear doing clutches is a PITA, so I'm not looking forward to doing this job twice :-/

Am I being overly paranoid here?

snipped-for-privacy@estaff05.mayfield.hp.com (Ted Johnson) wrote in news:e3rp6p$ snipped-for-privacy@estaff05.mayfield.hp.com:

Yes. Auto machine shops do this sort of thing every single day of the week. Don't worry about it.

I've done it both ways. The friction surface seems to last longer if the flywheel is turned, but this is based on the dozen or so clutch jobs I've done; YMMV. I also like the nice, shiney-new surface and the knowledge that the job is done *right* but that's just my OCD showing.

You might could call around for a good price at a junkyard, then have that machined. On "clutch day" you can just swap. Your risk is if the flywheel is somehow damaged (e.g. cracked), or that you've purchased the wrong flywheel, not having the old one for comparison. If you choose this route be sure the ring gear is in good condition.

Possibly. I've never had a problem with a machine shop turning flywheel or brake parts. It's a fairly simple task. My own choice, not knowing your local options, would be to disassemble, drop the flywheel off at the machine shop, take the old clutch parts to the store to compare with the new and insure that I'm getting the correct replacements, then swing back to pick up the machined flywheel.

Given that I have a reliable and trusty brake and clutch specialty shop in my town, I would probably take all down to them on a single trip. They will turn the flywheel at no charge if you buy the clutch components from them. Check your yellow pages under "clutches."

No; that's determined by the bell housing. The TB will need to move closer to the engine to disengage the clutch but most clutches have enough latitude in the adjustment to compensate for this. And, as another poster advised me, the TB can be shimmed if needed although I've never had to do this.

Oh, and speaking of transmission input shaft, at the risk of belaboring the obvious - don't forget a new pilot bearing.

-- Mike Harris Austin, TX

You arent meant to skim flywheels *really* though they did do many moons back, hence no info about it. If you are going to get it done make sure its a TINY amount removed, dont take it to a know-nothing mahinist - ive heard of some people having theirs reduced to below safe levels and burst when the engine was pushed - saw-toothed chunks of flywheel firing through the bodywork isnt fun. You could always buy an aftermarket one if it is cheaper (certainly is for my celica)

Yeah, next time you're buzzing your front drive Toy near or past the redline, keep in mind that all that rotating flywheel/clutch mass is aimed right at your crotch.

Lee Richardson Mech-Tech

It is in the US, In the UK and Japan people are smart enough to drive over on the other side.

But the same could be said for a stock, machined or "performance" light flywheel.

Anyway, moot point, as Coyoteboy's celica aint FWD.

It'd take out my missus instead :o( dont think she would find that funny. A performance one *should* be tested and withing limits.

Its a transverse mounted 4wd actually, so same engine location as the FWD versions.