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I have finally torn into the dreaded head rebuild, thanks to a blown Victor Reinz head gasket. NEVER AGAIN VR !!!!!!

I am not closely documenting the process this time, as my big rebuild document details how to accomplish the task. I will update this thread as I go, and add pics. if something unusual, or super cool comes up.

This time around, I will be having a local shop that I trust skim the head to make it lazer straight. I will also replace the exhaust valves this time, with the brand new set I still have wrapped in paper, and I will have the seats/valves cut to 3-angle. When it goes back together, the one thing I am debating is whether to use an original BMW head gasket, or Cometic MLS, but absolutely not a cutting ring HG.

The beloved bundle of snakes took the usual, dreaded couple of hours to remove, although it was easier now that I have a lift. Given how much bloody heat actually comes off those bad boys, I have decided I will have them ceramic coated as well.

While everything is apart, and there is TONS of room to get at all the parts in the nose, I will do the AC condenser upgrade as well.

I accept all good juju folks, and hope to have everything back together by end of January. Yeah ..... nothing goes quick, or is easy with an M. Such a love/hate relationship.

Jose

Jose, What about contacting VAC in Philadelphia about the gasket? A friend on Bimmerforums who is doing a mega $$thousands build on an M motor in Australia has bought most of his "head" parts from there and after much research his head gaskets for sure

I didn't think you could skim a s38/m88 head?

I am curious as to why you would think that. I would think any head could be skimmed and if a problem could be adjusted with head gasket thickness which I know VAC, amongst other providers, can supply in various thicknesses. I know many years ago, and I mean many, it was not a problem when I did an early Ferarri motor and I would think clearances there are as sensitive as on an "M" motor.

Heya Bert,

My machinist in Napa is a well known dude in his world. He was president of the machinist/engine builders association for a bit, and has great contacts all over. On his recommendation I bought valves and springs for my M10 build from VAC, and we are happy with the stuff, but I have heard some troubling things about VAC of late. Has to do with a recent change of ownership (sadly, the founder passed away). Granted, what I have heard is second hand info., but it's reliable enough to cause me some concern as to VAC continuing to function at the high caliber their reputation stands at right now.

At any rate, the OEM is for sure a known good quantity, and Cometic continues to have a stellar reputation among high end engine builders, but I will definitely check out VAC's MLS. I had completely forgotten that they made one.

brickwhite - Maybe you are remembering that an S38 doesn't really have a specification written for what you can machine. BMW only states a minimum head thickness value, BUT there also is NOT a variable head gasket thickness. So the implication would be that if you shave the head, there would be no way to "fix" the problem of lost head thickness. As Bert points out, you can just shave it a touch, then make up for that thickness with the head gasket.

From what I understand Bert, Ferrari motors (especially the early ones) are built with manufacturing steps that essentially make each engine a freaking one-off. My machinist was sent a broken cam cap off a Dino (I think) that he had to measure and replicate exactly, because on that engine the caps were all bolted on, then machined in-situ. So every freaking cap has a different offset, on every engine ever made for that car. That is why Ferrari's are such a pain to work on. Every damn one is "off". BLAH! I'll take our German car precision any day of the week.

Jose

Hey Jose I am out of the No Cal car scene for 40 years when we used to race at the old Cotati air field, but drive down to Infineon Raceway and look up Dodge Riedy who has a shop there. I have known him since the mid sixties when he was a 16 year old kid. He knows his stuff and could be another great source.

As to the early Ferarri, to be honest, it was like putting 2 6 cylinder Chevys together. Other then the overhead cams, by modern standards, it was not a very sophisticated motor.We short blocked it on my dining room table. Worst part of that was my ex wife wanted to grab the crank shaft and have a lamp made out of it!! She was totally with the program. The base for our coffee table was an old Ferarri block. Wife #2 doesn't see things that way.

Why would you have not kept wife #1 ? Any woman who would to put up with an engine block (even a Ferrari) on a dining room table would be a real gem.

She didn't want to keep me.!! Oh well, ended up on the better side of good with #2 except she makes me keep the garage clean!

Ok folks,

Today I got the head off and did my triage. Here is the HG, and the culprit spot, between cylinders 4 and 5.

You can pretty clearly see there is actually an indent in the circled spot between the cylinders, which indicates that the HG might have been damaged, but for sure didn't compress fully when installed. Looking at the back, you can see the carbonation, and how the gases would have pushed up to the triangular openings, which are coolant passages. What's more, the webs between cyls. 2/3 and 3/4 also look like they might have been leaking. I will take the head to my machinist this week, to have him perfectly flatten the sealing surface, and install the new exhaust valves I still have in a box. I will also ask him to do a 3 angle on the seats/valves too.

Jose