DDK - Die Deutschen Klassiker

Recently I found a crack on my 2L engine case, where a stud screws directly into the magnesium. I really need some advice on how best to deal with it and prevent it becoming a serious problem. I could leave it, seal it or perhaps use JB weld, I just don't know.
I’m guessing to fix it properly would require an engine strip, but that may or may not be possible this year and be frighteningly expensive.

If you cant strip the engine to have it welded and tapped true after then if it isn't leaking oil I would leave it alone, but protect that crack from corrosion (which will make the welding so much harder later on) and JB would be a good material to use after really cleaning the area and the crack as deep as possible.

As it has cracked I presume there is a tread issue or over tightening responsible and you don't want that crak propagating further so a strip wilbe due soon.

Welding magnesium castings is a specialist job, but quite easy to find people to do this usually in the motorsport industry.

I suspected it had been over tightened, not by me but by someone who thought they were helping. For now I’ll give it a good clean and use the JB but, I guess I’m looking at a rebuild, something I was trying to avoid.
Thanks for your advice.

Speak to Alan Barker from EMP engineering, they weld both aluminium and magnesium crankcases - he'll advise on best way forwards.

Thanks, I'll certainly give Alan a call.

I can't actually see a crack in the photo ? ............ I see what looks like two casting "lines" - above and below threaded hole . Maybe just photo angle or my bad eyesight ??
If it's just a crack on the bottom - you MAY get away with an "in situ" spot of TIG (loosen bolt - good clean,weld and refit bolt to a lower torque ?) , to hold things together , untill you get opportunity to strip , fix properly and rebuild ??

Cortina wrote:I can't actually see a crack in the photo ? ............ I see what looks like two casting "lines" - above and below threaded hole

Yes, looks like that to me. Would need a photo of the other side of the raised casting line. Or even file off the casting line to get a better view?

Razor blade.
If you can get some in along the line...it's a crack.

911hillclimber wrote:Razor blade.
If you can get some in along the line...it's a crack.

..... and even if you can't ..... it could still be a crack !!! (Razor blades go in straight lines ... sometimes cracks don't)

OK, the corner of one!
Could be the casting flash 'line' but if oil tight I would leave it.

Thanks guys. Looking at it again it may well be a casting line.