flywheel machining when renewing clutch?

tommo · Post by **tommo** » Wed May 30, 2007 9:59 pm

Hey all,
putting in a new clutch on the weekend, as my brumby is almost undrivable with the amount it's slipping now.
So I'm wondering about flywheel machining. I've been told you should get it machined when you put a new clutch in... how important is this? (if at all)
Thanks as always,
tommo.

Post by **Alex** » Wed May 30, 2007 10:07 pm

we just put a new clutch in my car. The clutch dude recommended that i get the flywheel machined, it gives the clutch disc abit more "bite". I didnt get it done because the flywheel has had the holes reamed out and loctite'd to the motor(ej22). Seems fine now, absolutely zero slip

alex

90brumby · Post by **90brumby** » Wed May 30, 2007 10:07 pm

if u ever want to claim warranty on the clutch you will have to machine the flywheel

besides that i have put 3 clutchs in 3 different cars and never machined the flywheel
but would recomend u get it machined

bpm · Post by **bpm** » Wed May 30, 2007 10:17 pm

have a look at the flywheel, if its got any hotspots, grooves or an uneven surface, get it on the mill. small surface cracks are generally ok. as others have said, warranty is void if you cant produce an invoice for machining, but if, like me, youve ever tried to claim a clutch on warranty, its just about impossible. i own a workshop and ive never had a clutch replaced, even after many attempts, machined or not.

Matatak · Post by **Matatak** » Wed May 30, 2007 10:31 pm

ive put a fair amount of clutches into cars without machining the flywheel on them. usually just inspect them then rub them down thoroughly with some sand paper.

wouldnt no how much it costs for a machine but, so depends on how thorough a job you would want to do.

Suby Wan Kenobi · Post by **Suby Wan Kenobi** » Wed May 30, 2007 10:48 pm

If your clutch has been slipping as much as you say you would heva heated it up enough to distort and crack it so i would recomend machining it i always machine my flywheels when installing a new clutch

AlpineRaven · Post by **AlpineRaven** » Thu May 31, 2007 7:34 am

I had an EJ22 in previous Liberty - replaced the clutch, I didnt get it machined because it wasn't recommended by Subaru mechanic, he said you can machine its up to me, if the clutch was metal to metal then yes, but I had a little beef left on it when it was slipping - it was fine. This Liberty I have now has warped flywheel (the clutch shudders before catching) and its annoying but I got used to it - when it goes I'll get it machined.
Cheers
AP

tommo · Post by **tommo** » Thu May 31, 2007 9:32 pm

Thanks for the feedback.
I found a mobile machinist today who'll come out on saturday, so I guess it's probably for the best. $60 he's charging, seems pretty reasonable to me.

Any other tips or things to watch out for when changing clutch?
I know about torqueing the bolts in the right order... that's all I've heard to be careful of though.

Cheers,
Tommo.

AndrewT · Post by **AndrewT** » Thu May 31, 2007 10:22 pm

Thats reasonable considering he's got to drive out to you. I just got some Lib front brake discs machined (both sides) and that was $30 per disc. I brought them in to a brake place myself tho.

Matatak · Post by **Matatak** » Thu May 31, 2007 10:34 pm

have u ever done a clutch before mate??

if you dont have a clutch alignment tool then youll need to take some care with gettin the disc pretty central enough for the shaft on the g/box to go back in properly

better hope he doesnt tell u the flwheels screwed aswell lol or itll cost a fair bit

Post by **Alex** » Thu May 31, 2007 10:56 pm

60bucks!...cheap as chips!

alex

AndrewT · Post by **AndrewT** » Thu May 31, 2007 11:04 pm

Nah you don't, thats the slow way...

You do the pressure plate bolts up tight enough to hold the clutch (close to the centre as you can get it by eye). The put the gearbox on, the shaft will allign the clutch itself. Then you can do up each of the pressure plate bolts one by one by accessing them through where the starter motor goes.

Don't know if this is possible on any other car but it works a treat on a suby!

This wouldn't be advisable in a 600hp race motor situation but is perfect in this case.

90brumby · Post by **90brumby** » Thu May 31, 2007 11:19 pm

yep thats a good way to do it on a subi doesnt wrk on most other cars casue the stater motor sits on the other side of the motor if u no wat i mean

tommo · Post by **tommo** » Fri Jun 01, 2007 6:22 am

Ahh, I was wondering what i was going to do about that clutch allignment tool, was thinking about turning one up on the lathe at work today.
But the lathe's not working too well so it'd be a whole lot easier if I didn't need one at all.
Thanks a lot fellas,
I'll let you know how it goes.

Matatak · Post by **Matatak** » Fri Jun 01, 2007 9:28 pm

should be easy to do without the alignment tool neway but thelast time i saw an alignment tool was round 50 from repcos..but this is in Perth
aparently the g/boxes are easy to take out on these old subis, accordin to my boss neway who use to work on them when he was doin his apprenticeship

neways good luck with the clutch

SUBYDAZZ · Post by **SUBYDAZZ** » Fri Jun 08, 2007 7:12 pm

Last time I did a clutch I used an old input shaft BYB01 gave me. This time I didn't have one so by the time I had the box out I decided that spending $25 on a tool to align it to ease replacement was well worth the money. The one I got wasn't suitable (as I discovered when I went to use it) as it didn't have a small enough fitting (several in kit) to go into my spigot bearing so I had to backyard it by wrapping some electrical tape around the thread where the fittings did go. Worked a treat.

BTW I pay $22 per brake disc for machining and $44 for the flywheel (stepped or flat) at my local Brake & Clutch place - for comparison.