SOHC.co.uk Forums > CB350/400

Engine oil leak

(1/2) > >>

rosco:
Hello all Im back online after many months away ( not in prison )
On returning to the garage ,My CB400/4 has developed an oil leak which is coming from the front nearside engine mount ( I know, Bolt to long ) But is it possible to just split the lower crankcase off Without a full strip down once the engine has been removed. The old brain cells are a lot  rusty after a long lay off Please be gentle ??  Thanks

exvalvesetdabbler:
Yes, I did that to replace the primary chain and cam chain. You will probably need some new seals that blank off the ends of the gear shafts. All the gears will stay in the top half of the engine when it's upside down. Just be careful of any loose dowels or split ring bearing retainers dropping into the works. I think the gear selector arms will need to come of before splitting.

Dave

McCabe-Thiele (Ted):
Are you 100% certain as to the source of the oil leak?

Very easy to find what you think are cracks in the casing that turn out to be casting marks.
Oil can easily run down from the cylinder head etc.

Yetanotherbike:
As a youff, incredibly, despite the warning in the Haynes manual, I managed to get the bolts mixed up. The inevertable happened when I torqued the engine mounting bolts up and I heard a large cracking noise. I could see the crack adjacent to the engine mounting lug which if memeory serves me correctly is next to an oil gallery.
A mate reckoned he could weld it, however it still leaked, so I ended up getting another crankcase from a breakers yard.
I would not consider mixing crankcase halves for a millisecond. So in a worst case scenario I would prepare yourself for a full strip down.
However As McCabe-Thiele (Ted) quite rightly suggests, double check that the crack is in the casting before you assume the worst.
If the worst is the final conclusion, then you're in the right place for an answer.

exvalvesetdabbler:
If it's on the left side, don't rule out the seal on the final drive or build up of oil thrown off the chain  that's trickling down.

I would remove the sprocket cover and give it a generous dose of gunk and then see where fresh oil emerges before pushing the panic button.

It's easier to put a thick feeler guage in when tightening these bolts and stop once the feeler guage is tight.

Regards
Dave

Navigation

[0] Message Index

[#] Next page