Head bolt question (pg. 3)

[demetk]

Often rocker shafts on M30s require a considerable amount of force to move them. Regardless...

Here is a pic. Note the short shoulder and the notch it goes into which is already recessed some into the head.

Wow, I had no clue what you guys were talking about, until I went and had a look-see on one of my heads. Now I understand. So will the shafts align themselves with the bolt holes when the bolts go in or do they need to be tapped into alignment before you install the bolts?

[Mike W.]

No, it's gotta be close. If it's close enough it'll self align, but it's got to be pretty close. But you can work it by feel and go from there.

[VW+bimmer=bliss]

Wow, I messed up
when I had unwrapped the cylinder head, I almost immediate ly put it on the block. When I had about half of the bolts in, I noticed ALL of the eccentrics were not facing the right way. No bolts were torqued down, just barely finger tight. So I took the head off, and proceeded to turn the cam so I could relieve spring pressure on some valves. I stopped when I noticed the rear cover gasket had been damaged by the machine shop, no biggie wish they had told me, but I had a spare, removed the cover and proceeded to turn the cam ( NO head bolts are in at this time) maybe 180the degrees of rotation later the rockker springs forced the intake rear shaft out of the head. Keep in mind this was after i had lightly tapped the intake front rocker shaft to move the rear one so I could put the head bolts through. I put the head back on the block and held the rear intake rocker shaft with my finger and put the headbolts in, still, the rockers sat over the edge of the cam lobes on cylinders #4,5 and 6. I am very confused as the other ocker shafts did not budge at all with no bolts in their respective holes. I took it back to the machine shop, and they said they can make a spacer to fit on the end of the rocker shaft plug underneath the rear cover. Could this be detrimental to oil flow in the rear part of the head? It is just to hold the rocker shaft in place so the rockers them selves will be held in the middle of the cam lobes and so I can also put the head bolts in as well, thoughts? I am very frustrated as to why only this shaft is not staying where the others stay just fine.

[VW+bimmer=bliss]

So thoughts on the spacer to hold the shaft in place? I thought it would be fine since oil neither enters or exits from that point of the rocker shaft. This is under the rear cover with the duck looking gasket.
Jon

[Mike W.]

I can't think of why it would be a problem, but why do it when all you have to do is wiggle and push the shaft while you run a bolt down. You don't have to torque it, just run a head bolt down and it should locate it.

And it doesn't strike me as odd that 3 stay in position and one moves, it's kind of random as long as the head isn't warped much.

[VW+bimmer=bliss]

Damn, did not realize how big that picture was haha.
even with the head bolts in, the shaft was no where near where it was supposed to be, the rockers sat almost 3MM over the edge of the cam lobes. Awesome, Thank you Mike for letting me pester you for information!