Engine help needed

[Nbecker100]

Blew head gasket in my 1991 318i due to overheating, not sure of the cause because I replaced the whole cooling system. I'm assuming the block is clogged. I replaced the head gasket but I still have milkshake under my oil cap and it has a decent bit of blow by now. I had 0 blow by before I took it apart. Any idea why it has blow by now? All help is appreciated

[bmwman91]

It is common for the M42 to crack the head when overheated (especially badly enough to blow the HG). Did you get the head resurfaced and inspected when you had it off after the initial failure?

[Nbecker100]

bmwman91 Nope, I never got it inspected or resurfaced

[bmwman91]

Well, it sounds like you have an opportunity to pull the head and inspect it. At a minimum, reinstalling a 30+ year old aluminum head without having it machined could easily be the problem even without any cracks.

[Nbecker100]

bmwman91 Ok thanks, I'm thinking of doing a m50 swap instead of messing with the m42

[jsnppp]

Thats a major change of plan :-)