928Belgium

Hey Guys, here is a little update
I took appart the heads and cleaned everything.
In a machine shop they did a pressure test => result ok
They skimmed the head the minimum amount necessary => 0,1mm which equals 0.004 inch
changed the valve guides and had the valves + seats cut

Today I "lapped" the valves with paste and starting to put everyting together
While putting together the very last valve I noticed that there was a little piece cracked from the valve collet. Schould I have change them all?

928Belgium

928Belgium

928Belgium

The Forgotten On

I would replace them as they are old and you wouldn't want a dropped valve after going through all of this work.

928Belgium

Hello, here's a quick update because I had some spare time last weekend.
And also because I have a little dilemma.
So I changed the collets. After cleaning the block I screwed in the new studs with Loctite.
I thought I measured them all (sticking out around 70mm).
After putting the head on with the new gasket and torquing the nuts to specification I noticed that one nut isn't screwed all the way (between 1/2 and 3/4 turns compared with a nut flush with the stud). I don't know what went wrong, fault with the measurement, thicker washer or did the stud screwed further in during torquing which is doubtful with the loctite.

Now I have 3 options:

-leave it that way wondering what the risk is of a stripped nut from the force on less thread
-loosening the nut and using a thinner washer, but can loosening one nut wrap the head?
-taking off the head and trying to descrew the stud on the correct length but this mean buying a new head gasket and risking that the stud don't come loose with the loctite?

What do you guys think I should do?

Dave928S

I think it's unlikely to be critical, as there's almost complete engagement anyway, and if it was mine I'd leave it be. Just my opinion of course, and I'd rely on someone much more experienced to chime in and give definitive advice.