[DaveS]

I'm just cleaning up the cylinder head on a 1989 9000 turbo 16valve 2 litre B202 engine.

Everything looks reasonably within tolerances except the valve head diameters. Mine look fairly clean, not badly eroded (for 89000 miles) but the inlet diameter is 29.5mm and the exhaust is 26.5mm - Haynes quotes 33mm and 29 respectively.

Does anyone know if Haynes is correct? These valves certainly don't look to have eroded by that much.

Any help appreciated, thanks in advance.

 

[Dazzel]

Firstly I would take the haynes manual with a pinch of salt, and secondly valve heads do not tend to decrease in size unless the valve is very badly burnt or the valve has been refaced excessively which would leave an almost razor sharp edge around it's circumference, which is highly unlikely (unless the guy who refaced them was a complete monkey).It's probably more feasible that haynes have got it wrong again(big surprise).I do not have the specific sizes to hand but I can get them if necessary.I hope this helps you.

Cheers Darren

 

[DaveS]

That's reassuring anyway - the valves all look OK, even the stellite coating on the exhausts, and the edges are the correct shape.

It makes me wonder about the valve springs, now. Haynes quote 45.5, mine are all exactly 42. I don't suppose anyone has a correct spec for these, have they?

Thanks for your help.