Burning clutch, clutch drag ?

[bobo83]

My 2zz donor car has a strange issue with the clutch: it burns at the slightest slippage.

I got the car without history and it had a slipping clutch. I changed the clutch myself (third time doing such a job, the other two went well). However, since I installed the new clutch, I can smell the clutch very very often when driving normally.

At first I thought it was okay given that new clutches have a break-in period, but it's been happening for the last 2000 miles. I drive plenty of other manual cars and all is good, so it's not user error.

The other problem that I have is that for the first few miles, it is hard to disengage first gear ?!? I have to add revs to be able to take it out of first. Some gear changes are also notchy. Engaging reverse always grinds a bit, even if I wait 5s after pressing in the clutch pedal.
Sometimes I have unstable idle that seems to stabilise when I press the clutch pedal.

I don't believe it is the gearbox that is at fault, it drove fine with the slipping clutch for the 50 miles or so I drove it. I bled the slave cylinder, adjusted the pedal ... nothing worked.

The flywheel has some burn marks from the slipping clutch, could this be the reason? Is it a bent clutch fork? Failing slave / master cylinder?

Any ideas are welcome.

This is what the flywheel looked like:

You cannot view this attachment.

[Carolyn]

It sounds like you got a defective clutch plate.

[bobo83]

Thanks Carolyn. I used an OEM-quality Aisin clutch but something must be defective.

Does the flywheel above look okay to you ? Don't really want to pay for a new one.

[Carolyn]

@bobo83

I've seen better.  A bit burnt but not grooved.  I'd de-glaze it with some 400 grit wet and dry.

Edit:  On second thoughts, 250 grit on a hard flat sanding block. 

If that doesn't improve it, you could take it off and take it to a machine shop that can surface grind it.

I don't think it would be the cause of the trouble getting gears.  That sounds more like a clutch plate with a bad spring resulting in uneven spring tension, so that it is neither exerting even pressure or able to properly come clear of the flywheel.

I've taken clutches out that had obviously uneven 'fingers' and they exhibited the same symptoms.

[bobo83]

@Carolyn, thank you for the advice, will try to sand the flywheel!