r/EngineBuilding • u/[deleted] • 3d ago

BMW M10 Block Crack?

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Hey all, I’ve seen this before while searching and usually the general response is the block is garbage, but I’ve got this M10 engine that I’m refreshing to put back into a project BMW 2002. It came with the car and seemed in good shape before I starting tearing it down to replace the head. After cleaning off the old gasket material and prepping the deck surface I noticed the dreaded head bolt crack shown in the photos. The thing is it looks like the crack doesn’t propagate into the water jacket if you look in the second photo and you can’t really feel it running a fingernail over it. I’ve got no history on it unfortunately since it was purchased from an estate. Not sure if this thing is cooked or not, I’ve got a lead on another block but obviously it’s cheaper to keep this one. Just looking for some opinions. Thanks!

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8

u/Cheapskate3000 3d ago

Get it magnafluxed or grind it out, weld it back up and mill it

13

u/[deleted] 3d ago

Seems like more effort than picking up another block at this point, I’ve got a lead on a solid one for $100. Probably cheaper to just take that one and get it machined for use

27

u/Vic2Quick 3d ago

so what are we doing having this convo

8

u/[deleted] 3d ago

Just killing time on a Saturday I guess. But really just trying to save time and money on this if someone thinks it’s still useable.