Yamaha TRX850 Enthusiasts Forum

I have noticed since riding my TRX (1996 model) this year that the oil level has increased slightly over time. When I had the bike serviced in July I mentioned the increasing oil level to the mechanic and that I could also smell petrol in the oil. I got the mechanic to replace the seals in the fuel tap after reading posts on this forum where members had experienced similar problems. Since replacing the seals (which the mechanic used genuine Yamaha parts) and after not riding the bike from the end of September the increase in oil level has got so bad that it is now up to the filler cap.

After reading several more posts I decided to check if the fuel tap, pump or both were the problem. Firstly, I loosened the vacuum hose from the tap which was dry. I then loosened the hose from the tap to the pump which leaked fuel whether set to "on" or "reserve". I then loosened the hose from the pump that supplies fuel to the carburetors which again leaked fuel. I believe that if the tap is set to "on" or "reserve" with the engine not running that no fuel should flow. I'm guessing if fuel is leaking past the tap and pump this is why the oil level is rising. If so have the tap and pump both failed at the same time or is it just the tap? I have seen used taps and pumps on Ebay are they worth a punt or am I wasting my time.

Any help or advice would be appreciated.

Cheers

It`ll be your tap, it`s not functioning properly and should only release fuel under vacuum. It WILL however allow flow if turned to PRI (prime) whether the engine is running / turned over or not.
Fuel tap repair kits are available on Ebay now (I think). And if not try contacting NRP:

http://www.nrp-carbs.co.uk/yamaha_fuel_ ... ir_kit.htm

The TRX is not listed but they`re a very helpful lot.
By the way, I sincerely hope you are not running the bike with this petrol-oil mix as lubricant?
You WILL ferk bearing / component surfaces very quickly!

Try this:

Turn the fuel tap to OFF, change your oil and filter COLD, do not run the engine. Then use / run the bike but as soon as you stop it turn the fuel tap to the off position and do not turn it to on again until you are going to use / run the bike. Monitor your oil level in between.

with the tank in place, you can check the tap by disconnecting the fuel out line, putting it in a suitable container, and using a syringe and some aquarium air line to generate vacuum see if the fuel flows on demand.
neither of my TRX have an 'off' position on the tap.
they only have on, prime or reserve.
cheers
fung

Damn you`re right fung!!!!!
That`s the problem with not being around the TRX all the time as you Aussies are, and being blessed with great weather for much more of the year that we are over here in Scotland can merely dream of.
Today`s howling gale and driving rain bearing testament to that!

Ok, well in that case disregard all the utter sheeite obout turning the tap to OFF I spouted on my last post Milan Mule.

Mince
hard times are over
immigrate mate