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

pedrosan · Senior Member

Oil Leak around the front right hand side of the engine

TTRfan · Super Guru

The bolt going down into the crankcase is an oil bleed screw - very useful to check the engine has oil pressure after a rebuild wink

Not known them to leak though. Are you sure the oil isn't dribbling down from the descrpressor plug on the LH side of the engine?

Maybe give the engine a really good clean and then run it up and see where the oil is coming from?

Brian

TTRfan · Super Guru

Any chance of a pic of the RH side of the engine?

pedrosan · Senior Member

Ive done the decompressor plug as this was leaking when I got the bike, I'll take a pic of the other side and stick it up, cheers. Out of interest, is there a washer on that bolt? I may try replacing it anyway as the easy option.

TTRfan · Super Guru

pedrosan wrote:
Ive done the decompressor plug as this was leaking when I got the bike, I'll take a pic of the other side and stick it up, cheers. Out of interest, is there a washer on that bolt? I may try replacing it anyway as the easy option.

Pretty sure there is a copper washer. Easy fix would be to take it off and anneal it.

Brian

pedrosan · Senior Member

Cheers Brian, I seem to remember the description of annealing on your modernising thread, I'll look it up and get that done soon. Fingers crossed its a quick fix!

TTRfan · Super Guru

pedrosan wrote:
I looked at the other side of the engine and the bung I had replaced 4 months ago at the compressor hole has gone already. I'll get a new one (any ideas where the best place in the uk is for them, I tried a search but couldn't get any joy) and put it in myself.
Cheers, Pete

The standard bung leaves a bit to be desired

Brett from Taiwan got someone to machine up a replacement in ally and banged it in with a bit of sealer for a much more permananent repair. Do you know anyone with a lathe?

Martin at MotoWard should be able to sort you out as you have the part number but another owner said the bungs were no longer available and you had to buy a whole head - see http://ttr250.activeboard.com/t48028573/decompressor-blanking-plug/ confuse

If you get stuck send me an email coz I have a couple of new Yamaha bungs tucked away safely here at TTR Towers wink

Brian

pedrosan · Senior Member

Well following other posts on this bible-like forum, I went to a russian site with the parts lists on, they seemed more comprehensive than those on boats.net but I may be wrong.

This is the bolt I was on about, and Brian by the looks of it you are correct, it has a washer.

leaking possibilty.png

I'll take it off, anneal the washer and put it back just for peace of mind.

Annealing as per yet another post (Brians project bike) is heating the washer up until its cherry red then dunking it in cold water to cool it instantly.

I looked at the other side of the engine and the bung I had replaced 4 months ago at the compressor hole has gone already. I'll get a new one (any ideas where the best place in the uk is for them, I tried a search but couldn't get any joy) and put it in myself.

Cheers, Pete

pedrosan · Senior Member

Thanks Brian, you're a legend. I'll try and get someone to do me an ally one, I like the sound of that. Can't believe its gone so soon, really disappointed. Hopefully between that and the washer I'll get to the bottom of my oily engine...