Warped Head

[hoveringuy]

I bought the motor from the P.O. who had overheated it when his expansion tank failed. Sound familiar?

Upon teardown, the head had no cracks but was bowed up .010 in the middle.

My options are:

1) bolt it back in place with fresh head bolts and head gasket, hope it bends back enough. Really, what's .3mm between friends?

2) Skim the head. Install with a thicker head gasket. Hope cam doesn't break next year because the upper head is still warped.

3) Send head to be straightened. Hope it doesn't crack in the process. Write a big check.

What would you gus do?

Hoveringuy

[paraklas]

What engine is it?

[hoveringuy]

M54B30 from a 2001 E46.

Also, is this head the same casting as the 2.8 litre version from 99? I'm looking at purchasing one that was pulled from a block that took a piece of steel from the road. Block was destroyed but the head was fine. Never mind. I think that's an M52tu.

The shop says they can't pressure test it because they don't have a plate wide enough, but it looks really good and there is no scoring on the lifters and the valves seal fine.

So, what is the prognosis if I have this head heat straightened, skimmed, and then valves re-seated? Check would only be $450, not as much as I thought.

[SL Blak Soldier]

I say get the head decked, and get a thicker hg.

[Ted13B]

Before you do anything, BMW issued a bulleting warning that bad overheats will often warp the head, pulling the head bolts (and threads) out of the block. Drop the head in place and try to torque the bolts. If they won't torque, the block is junk.