Oil leak between cylinders and gearbox...

Moderators: trixynut, Mincehead, dicky, phuk72, Jak, Kevtrx849

User avatar
trixynut
Site Sponsor
Posts: 2572
Joined: Fri Sep 22, 2006 3:48 pm
Location: Leicester, England

Oil leak between cylinders and gearbox...

Post by trixynut » Thu May 14, 2009 9:54 pm

Image

Image

Image

(Photos: cylinders on left, gearbox on right, taken from left side of bike)



Got a leak, behind the cylinders, in front of the gearbox. You can see the oil pooling around the bolt for the casing, bottom left in the second pic.

The external oilway is covered in oil, as is the base of the gearbox but the cylinders seem fine, so I was thinking the rose joint/bolt where the external oilway goes into the engine, but this is as tight as it can be. So what else?


Does this connection have copper or similar washers which could have gone? (looks like it in the pic)
Base gasket for the gearbox?
External oilway cracked? (never heard of it but..?)
Anything else?


What are my options for finding out? I'm thinking tank off, airbox off, clean it all and run the bike to see whats weeping and from where?

Cheers

Dave.

User avatar
Mincehead
TRX-Enthusiast
Posts: 6345
Joined: Sun Jan 25, 2009 1:40 pm
Location: West Sussex
Contact:

Re: Oil leak between cylinders and gearbox...

Post by Mincehead » Thu May 14, 2009 10:35 pm

Ok,first of all a degreaser and wash off,don`t run the bike just use an old paintbrush for the degreaser and something like a washing up liquid bottle filled with water to forcefully wash off the oil contamination.
I`m doubtful it`ll be the externall oil pipe that`s split,never known a mild steel oil pipe to go,although any flexible sections are weak points obviously.
It could be the banjo come loose but again it`s not very common.It could also be a stress crack on the cases,again VERY rare but I`ve seen it at oil gallery banjo`s before.
I`m guessing it`ll be the oil tank gasket(underneath the oil tank)loose filler cap,or maybe even the breather hose from the cam cover(split/perished).
A good way to find a slight/slow leak is some talcum powder around the dried engine,oil will show very quickly on it,just run the bike up to temperature on tickover and keep watching. :wink:
LOUD PIPES SAVE LIVES

User avatar
dandywarhol
Site Sponsor
Posts: 1639
Joined: Fri Nov 24, 2006 12:56 pm
Location: Edinburgh, Scotland

Re: Oil leak between cylinders and gearbox...

Post by dandywarhol » Thu May 14, 2009 11:40 pm

Or the breather pipe at the camcover kinked/blocked causing crankcase pressure to build up and pee out oil and mist.
1996 TRX 850, blue, Ohlins 46HRCLS, Race Tech Gold Valves, 0.90 springs, Venom pipes, R6 brakes............
1974 Yamaha RD250A, Candy Blue
1998 Yamaha SZR660, blue of course
1967 Yamaha TD1C 250, Blue and white

HansJ
Site Sponsor
Posts: 683
Joined: Fri Sep 01, 2006 9:27 pm
Location: Stockholm, Sweden

Re: Oil leak between cylinders and gearbox...

Post by HansJ » Fri May 15, 2009 6:53 am

It's not as simple as "someone" having missed the hole when filling oil?

If not, then the other recommendations before me could have been mine as well... Gaskets/washers for the valvecover, oilpipe, oiltank, breather. Can't remember how the airbox looks like, but if there's oil in it, I recall it has a hole for letting oil out?
IQiokW
*** Stalwart of the Sight ***

User avatar
idl1975
TRX-Enthusiast
Posts: 749
Joined: Wed Feb 21, 2007 9:19 am
Location: Surrey

Re: Oil leak between cylinders and gearbox...

Post by idl1975 » Fri May 15, 2009 9:08 am

HansJ wrote:It's not as simple as "someone" having missed the hole when filling oil?

If not, then the other recommendations before me could have been mine as well... Gaskets/washers for the valvecover, oilpipe, oiltank, breather. Can't remember how the airbox looks like, but if there's oil in it, I recall it has a hole for letting oil out?
Yeah, that would be my first thing to check - if you spill oil while filling (overfill or miss the filler) it will end up where it is in the pic. Clean it, then run it and see if you get fresh contamination.
-----

'04 Aprilia Tuono Fighter
'00 Scooby Sport Wagon

'76 TY250.

User avatar
trixynut
Site Sponsor
Posts: 2572
Joined: Fri Sep 22, 2006 3:48 pm
Location: Leicester, England

Re: Oil leak between cylinders and gearbox...

Post by trixynut » Fri May 15, 2009 1:04 pm

Don't think its an oil spill as I've not topped up for a while and the oil on the motor is definitely fresh.

I've checked the crank breather and the drainhole from the airbox and its not that.

Just seems odd that the 'oiliest' bit is the external pipe. Makes me think it is coming from above that.

Maybe I should be looking at the right side of the bike around the oil filler pipe area. The oil on the bike is on the left side but that may be because thats the way it leans on the sidestand.

Think a partial stripdown, thorough clean and a run with it on the paddock stand is in order, and hope its nowt too major!!

User avatar
idl1975
TRX-Enthusiast
Posts: 749
Joined: Wed Feb 21, 2007 9:19 am
Location: Surrey

Re: Oil leak between cylinders and gearbox...

Post by idl1975 » Fri May 15, 2009 2:13 pm

trixynut wrote:Don't think its an oil spill as I've not topped up for a while and the oil on the motor is definitely fresh.

I've checked the crank breather and the drainhole from the airbox and its not that.

Just seems odd that the 'oiliest' bit is the external pipe. Makes me think it is coming from above that.

Maybe I should be looking at the right side of the bike around the oil filler pipe area. The oil on the bike is on the left side but that may be because thats the way it leans on the sidestand.

Think a partial stripdown, thorough clean and a run with it on the paddock stand is in order, and hope its nowt too major!!
DOH! #-o #-o #-o #-o #-o

Well, hopefully it's something you DON'T have to drop the motor to fix.
-----

'04 Aprilia Tuono Fighter
'00 Scooby Sport Wagon

'76 TY250.

User avatar
slow codger
Site Sponsor
Posts: 2699
Joined: Sun Oct 01, 2006 9:35 pm
Location: The Fens

Re: Oil leak between cylinders and gearbox...

Post by slow codger » Fri May 15, 2009 8:58 pm

:? New copper 'O' ring at the bottom of the banjo? thats where it looks to have been weeping.

Dave E
An infiltrator from the dark side!

ekoja
Site Sponsor
Posts: 1370
Joined: Fri Mar 31, 2006 1:45 pm
Location: Gold Coast Australia. GOOOSD.

Re: Oil leak between cylinders and gearbox...

Post by ekoja » Fri May 15, 2009 9:49 pm

Sherlock had a similar problem on his Diversion at Walcha IIRC, I just cannot remember what the fix was.
You there Scott?.

User avatar
steve speed
Site Sponsor
Posts: 1780
Joined: Sun Jan 14, 2007 9:11 pm
Location: rochdale England

Re: Oil leak between cylinders and gearbox...

Post by steve speed » Fri May 15, 2009 10:07 pm

the trick with copper is get it cheery red with heat then drop in cold water ,,hey presto new soft copper washer ,,, we used to do this with triumph head gaskets
TRX850 ,The thinking mans R1

User avatar
Mincehead
TRX-Enthusiast
Posts: 6345
Joined: Sun Jan 25, 2009 1:40 pm
Location: West Sussex
Contact:

Re: Oil leak between cylinders and gearbox...

Post by Mincehead » Fri May 15, 2009 10:34 pm

`Annealing` is the technical term Steve,it`s used to make the copper more ductile.
Quenching isn`t necessary,in fact it`s better to heat the copper to `dull red` then let it cool naturally. :wink:
And yes,unless copper`s badly deformed/compressed it`s always reuseable.
By the way,similarly you can soften/anneal aluminium the same way but to guage the correct heat a wee bit of washing up liquid can be used,this will boil off and the aluminium will blacken,this is the point to take away the heat source and allow the worked piece to cool.
LOUD PIPES SAVE LIVES

User avatar
steve speed
Site Sponsor
Posts: 1780
Joined: Sun Jan 14, 2007 9:11 pm
Location: rochdale England

Re: Oil leak between cylinders and gearbox...

Post by steve speed » Sat May 16, 2009 9:26 am

i just rub a bar of soap on aluminium and when it turns black,,,, bingo bango,,, same thing really :D :D
TRX850 ,The thinking mans R1

User avatar
trixynut
Site Sponsor
Posts: 2572
Joined: Fri Sep 22, 2006 3:48 pm
Location: Leicester, England

Re: Oil leak between cylinders and gearbox...

Post by trixynut » Sun May 24, 2009 3:45 pm

Image

..ok, so sprayed with degreaser, cleaned thoroughly, dried, and went out for a blast.

Got back, and the investigation has turned to the right side of the bike..

..there's oil on the main external oilway from the oil tank to the right front of the engine (the 'shiny pipe') and some spots above this on the end of an overflow pipe but as its from the carbs, its not that. So working upwards from there, theres no oil coming out from any of the gaskets on the oil tank (bottom one or middle one) and no oil on the small diameter external oilway that runs from one side to the other at the back of the cylinders, but there is oil on the oil filler pipe.

So, I'm pretty sure I've worked out what it is ................................. but I'm not saying!! :oops:

.. but theres a clue in the photo!! :D

User avatar
Mincehead
TRX-Enthusiast
Posts: 6345
Joined: Sun Jan 25, 2009 1:40 pm
Location: West Sussex
Contact:

Re: Oil leak between cylinders and gearbox...

Post by Mincehead » Sun May 24, 2009 3:57 pm

Split filler cap O ring?
Sorry I cannot view those images at this pc.
Last edited by Mincehead on Sun May 24, 2009 3:57 pm, edited 1 time in total.
LOUD PIPES SAVE LIVES

User avatar
Jak
Site Administrator
Posts: 4787
Joined: Thu Mar 30, 2006 11:21 pm
Location: neither here nor there

Re: Oil leak between cylinders and gearbox...

Post by Jak » Sun May 24, 2009 3:57 pm

8-[ there's no cap ... or am I being blonde (again!)
This forum is (and will remain) free of advertising
Please help keep it that way : click here for details of how to donate towards forum costs

Post Reply