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crack in lower crankcase

ajh1

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Hi
So I thought I'd check the oil strainer as I have the engine out currently on my 80 cb750fa, lucky I did as someone had been quite handy with instant gasket:) But then I found this crack in the case. It looks like its only a surface crack in a non stressed part of the case. I wondered if anyone had seen similar cracks in cases. Hoping someone will say are they are common casting marks or something
Cheers

cb750f sump 1.5.jpg
 
Looks like you struck GOLD in the strainer!!!!! Nice nuggets! Might want to get that heliarc'd. Probably not a big deal but just for piece of mind. Wierd place for a crack though. I this the 1st time you have taken the pan off? Who knows how long it has been there since it is not an outer wall leaking oil.... Is the crack all the way through?
 
1st time Ive had pan off. I think its just a casting inperfection and probably been there forever. Apparently other people have seen similar cracks.

I'll just check it again when I next change the oil
 
On my own 1980 K there are similar-looking features inside the oil pan, but they're all raised "hairs" even though they look like cracks. On mine I could definitely tell they were extra material from the casting process. It's hard to tell from the photo whether that's an actual crack or a line of additional material on top of the smooth surface beneath.
 
On my own 1980 K there are similar-looking features inside the oil pan, but they're all raised "hairs" even though they look like cracks. On mine I could definitely tell they were extra material from the casting process. It's hard to tell from the photo whether that's an actual crack or a line of additional material on top of the smooth surface beneath.
Agree...mine has some...when i got my bike i shone a strong light under magnification to see it better.
I'd be more concerned bout whats on the strainer...bronze bits?...or slough??
 
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