Cylinder Head

[theman53]

I would imagine that the head is flat, so to get the notch you need you would just measure piston protrusion. It was flat from the factory, now it is just .008" closer, but still flat and needs the quench.

[Vincent Waldon]

Yup, head gasket thickness is determined by measuring piston protrusion... shaving the head don't factor into it.

[ffgb]

cool-thanks

[sdwarf36]

I took a 3 holer off-and put a 3 holler back on. Like was said-its the pertrusion.
 One reason why a machinist would suggest a thicker gasket is: unless there is a spec for head thickness, (most shops are members of AERA for $800 a year-one of the thing you get is access to "prosis" which list specs for 1000's of engines-sometimes there is listings for min head thickness-sometimes not-there isnt a thickness listed for our engine) is its hard to find a virgin. If you were the original owner,and you KNEW this was the head 1st time off, then it would be plenty safe to cut that .008--but how old is the head? 25 years? Has it been cut before? once? twice? Unsure? So he cut it just a little-but now the valves hit the piston--again it now HIS fault. (BEEN THERE!) So to cover his ass he suggests a thicker gasket-no power would be lost-and both you and he are happy.

[sdwarf36]

I take back something i said--there is a thickness spec---5.238 new---min 5.215.

[Vincent Waldon]

So he cut it just a little-but now the valves hit the piston--again it now HIS fault. (BEEN THERE!) So to cover his ass he suggests a thicker gasket-no power would be lost-and both you and he are happy.

Yup... I think that happens quite a bit.  The really thorough shop will cut the valve seats (re-sinking, if required) and valve stems by the same amount he's shaved the head... now everything is as the VW God's designed. 

[doonboggle]

Is it possible to plug weld (or whatever) the water flange holes in the head, and then have them redrilled and re-threaded by a machine shop?

If so, and if anyone has had something like this done by a reputable shop, who/where was the shop?
Not being versed in this, don't know how to shop the job, so one experienced would be nice to know.

TIA

[sdwarf36]

So he cut it just a little-but now the valves hit the piston--again it now HIS fault. (BEEN THERE!) So to cover his ass he suggests a thicker gasket-no power would be lost-and both you and he are happy.

Yup... I think that happens quite a bit.  The really thorough shop will cut the valve seats (re-sinking, if required) and valve stems by the same amount he's shaved the head... now everything is as the VW God's designed. 

VW-describe "really thorough"-is it the machinist does a bunch of work for free-or the "thiefin' jerk at the machine shop that tried to whack me $350 to surface my head?'  

BTW-looking at the Prosis for my 82-84 CY motor--it list valve rescession at .040-.060-so you got a plenty safe range.-Mine were .045 before I started. Its probably totally against the rules  -but I think i might bring it home + scan it + post up all the specs it lists.

[ffgb]

Hey Chris, you said Rimco shaved your cylinder head.  After all that material was removed, did you see any cracks in your PC's.  Did you have any problems later down the road with your PC's.  Did them peen them or not?  I haven't picked up my head yet.  Will do that tuesday.  I know it will be nice, clean, and shiny, but should I asked him to peen the PC's if he hasn't?

[Luckypabst]

They did not peen the chambers...
It's been a while but I seem to remember at least one crack in the face of one of the chambers which was there before the machine work.
No issues yet and I don't baby the van, other than keeping EGT limited to 1200 degrees.
Rimco didn't make any mention and I didn't think to ask but peening wouldn't hurt things. Stoning the high spots back down could cost a little bit, for the labor involved if you're not up to the task...


Chris

[ffgb]

Well, the machinist at the shop who rebuilt my head has never peened in the PC's, even though he said he was worried when resurfacing my head because in his experience, he said he had PC's fly from the resurfacing machine because they were knocked loose.  I guess I will peen them in myself.  Can someone recommend the actual tools used and angles used to peen the PC's?  Also, can someone post a pic of a finished peen on the PC's, so I know exactly where to start and finish?
Thank You