B31 oil leak

[750rideruk]

My 53 plunger has an oil leak! ( I know they all do) and seems to emanate from the crankcase into the primary side and then out via the gearbox shaft and the breather slot in the back of the chaincase. Does any of the fine experts have any solutions to this leak or at least to minimise it. Otherwise it seems to be reasonably oiltight. There does not seem to be any oil seals in the exploded diagrams on Draganfly just an oil flinger ring

[idie]

You are correct there is no oil seal on the engine, the breathing should be done via the pipe on the bottom of the timing cover. There is a metal disc in the unit coming out of the cover. If there is no pipe then maybe someone has fitted a cover from an M20.

[martinh10]

What makes you think it's coming from the engine? Does the oil level in the chaincase rise? I have had oil leaks in the past in the region of the gearbox sprocket and these turned out to be  chaincase oil due to a poor chaincase sliding plate/cork/felt seal and gearbox oil from between the gearbox mainshaft and pinion sleeve (worn bushes). Of course, as Idie says, check your crankcase breather first.

[750rideruk]

Thanks for your reply Martinh. I ran the bike with no oil in the chaincase and after a 40 mile ride I was able to drain oil from it, so thats my reasoning to assume oil is passing from crankcase to chaincase. I have a breather in the timing side also

[idie]

Is the oil returning back to the tank alright. Is the flap valve in the breather working alright.It could be increased crankcase compression due to a worn bore or a broken ring. Drop the sump plate and make sure that the ball in the pickup tube is free.