Porsche Enthusiasts Club Forum

I had the cam belt adjusted recently as the "toothed belt service" was coming on. The guy who did it (a local Porsche specialist) said that the cam belt/water pump were clearly new, but the belt needed retensioning.
It seems OK now, well the warning is not coming on and the engine has not blown up!

However, I'm worried about the tensioner, I don't think it's been rebuilt and I think it might be leaking oil (can't be sure, but there is oil in the vicinity of the tensioner if you look underneath the car)

I don't really have the funds to start paying for more dismantling. What is the purpose of the oil in the tensioner? If it is leaking how bad is that? Can it be removed and rebuilt without dismantling everything or should I leave it alone and stop worrying about it?

The oil hydraulically damps belt flutter, so prevents spurious belt tension warnings, especially when engine cold.

You could have oil leak from tensioner gasket, or more likely a cracked rubber boot. Or may just be coincidental that another leak in same area is culprit.

It can be removed without removing timing belt but apparently extremely fiddly, crank must be locked at top dead centre (or 45 BTDC if removing belt)m, and cams have to be zip-tied to stop valve springs rotating the cams. If that's not enough then by time you have stripped enough from front of engine to remove tensioner, you may as well do belt job.

There's very little oil in tensioner ( a few oz) so if leak stops soon then it was the tensioner!

Thanks for that. I'll keep an eye on the leak, but I think I'll leave the tensioner as it is, if it's not going to risk a cam belt failure.
I'll do it next time I change the belt. I've ordered the seal kit from 928 International (well I emailed them just for a price and they've sent the kit out....but that's OK)

No risk of belt failure with dry tensioner Lightning - loads of 928s are driving around with no oil in the tensioner but as it's designed to use the oil it's preferable to address that at some point. Counsel of perfection as I've not refilled my tensioner (there are two bleeders for filling) in 6 months of owning my car.

With no oil there is more risk of ultimate damage to the tensioner though, but it's not definitive and no-one knows timescale.