TheSamba.com :: View topic

Sun Jun 01, 2008 9:50 pm

Hi all,
Just a quick question to those of you who know diesels. I dropped my 1.6 off to have the lower end rebuilt, and the guy at the shop offered to rebuild the head, prior to that, I was figuring on just buying a rebuilt head. Anyway, I've got the motor back, the shop has really good references, but I noticed he machined the head. I'm not sure how much he took off of it, and I know it's standard practice to machine the head with Chevy's and such. I have, however, noticed that in my VW diesel books, that you shouldn't machine the head because of the pre-combustion chambers and such. I have a full warranty on the motor from this guy, 1 year, unlimited miles, but I'm a little worried as to whether he did any damage by machining the head. I measured the piston projection and I'm coming up with .026" which is a one notch head gasket, but if material was removed from the head itself, let's say .010, would that move me into the 3 notch head gasket to make up the difference between the piston projection from the block, and the fact that the valves are sitting .010" closer, or am I just over-reacting?

Mon Jun 02, 2008 6:35 pm

You might want to check this site out.

http://vwdiesel.net/phpBB/viewtopic.php?t=13205&highlight=head+machining

Tue Jun 03, 2008 12:29 am

Hey bvolks,
Thanks for the info, I checked with him and he said he did everything right, and reminded me again about the warranty, so I'd say he's pretty confident that he knew what he was doing. And, considering this motor will probably have about 30,000 miles on it within the first year, I guess if there is a problem, I'll find out about it in time for him to fix it.
As far as the other part of the question, am I correct in assuming now that there is still enough clearance between the valves and the pistons, regardless of what's taken off the head itself?

Thanks again,
Tim

Tue Jun 03, 2008 2:56 am

I wondered about that too but I guess since there are no combustion chambers and the head itself is completely flat it doesn't make the valves any closer to the pistons but the valve stems a bit closer to the camshaft. I assume the amount is small enough that they just a thinner shim when they adjust the valves or maybe they have to shave a bit off the valve stem itself so it's not too close to the cam. Not 100% sure.