A forum for owners of Yamaha TTR250 trail and enduro bikes!

Martinm · Veteran Member

Generator oil leak

TTRfan · Super Guru

The only persistent generator cover oil leak I have suffered was caused by a crack around one of the bolt holes in the cover that only opened up when the cover was bolted up Took me a while to find that one.

If your cover is OK then a decent gasket plus sealant should make it all oil tight. There must be something else happening. Could there be something trapped that prevents the cover fully seating?

Brian

Martinm · Veteran Member

Doesn't leak at all when engine is off just starts leaking when engine is running seems to come out through the wires I'll have to take it back off and investagate further hopefully covers OK 🤞after putting back on last time I would have garenteed it not to leek after putting sealent both sides of gasket 🙄

I've adjusted tick over now bikes runing lovely on tickover

Martinm · Veteran Member

Heres a link to my you tube channel I started bike up then turned it off and recorded results here youtu.be/f6E025VRtAg

Martinm · Veteran Member

Can't really see from that video

ttboof · Super Guru

Agree it's hard to see have you put sealer around the rubber plug the wires come through the gasket seals the rest but if the rubber is a bit hard you need a flexible sealant around the edge of the plug

Martinm · Veteran Member

Yes I put plenty around the side of the rubber plug I have since preasure washed engine to see where its coming from so took all the sealent off but I was very generous with the sealent because I didn't want it to leak again

Martinm · Veteran Member

Les you may have solved it my sealent may not be flexible, I used the red instant gasket I'll have to check it

ttboof · Super Guru

I used this stuff because for some reason locktite products are hard to come by around here

I only put it on one side of the gasket in case I wanted to take it off and made sure it was all around the rubber plug but only on the sealing surface.

Martinm · Veteran Member

I've now ordered simular flexible gasket sealer I'm sure this will sort it because now thinking about it the gasket stuff I used wasn't like the flexible stuff I've used in the past but I would of thought the amount I put on it would have sealed it and I left it a hole day before starting it up.
Anyway I'll try again

-- Edited by Martinm on Sunday 6th of January 2019 10:38:01 PM

Martinm · Veteran Member

Re done with flexible sealant still leaking slightly 😡😡😡

JOHNYBOY · Super Guru

but have you cleaned all the oil off with brake cleaner so it is dry for the sealer & let it cure another thought your crankcase breather is not blocked causing crankcase compression so it is leaking from the weakest point just a thought john

Martinm · Veteran Member

I cleaned oil off with carb cleaner and given plenty of time to go off but when I took bike for a spin exhaust got red hot and I touched the gasket sealer and it went back to liquid so that maybe why it's leaking again

Martinm · Veteran Member

Or it may have a crack in side cove like Brian suggested

ttboof · Super Guru

Bugger it's still leaking maybe it's a rare crack in the cover

It's not uncommon for sealant still exposed to air not to set they use the exclusion of air to trigger the curing process . So the sealant on the clamping faces sets leaving the excess to be wiped off .

Different with silicon based sealants where it all sets

Learnt this from a loctite rep when we had sealant and thread lock setting in the containers if not stored clean and correctly

Martinm · Veteran Member

Thats interesting about the sealant les, think mine needs new cover
Anyone got a spare cover that's not got any cracks in 😉

JOHNYBOY · Super Guru

ttr steve is your man plenty of parts & good advise