Yamaha TRX850 Enthusiasts Forum

Daft laddy question time but I need to make sure....

Can someone tell me where each of the following pipes end up (see first pic):

• The tube that comes directly from the underside of the fuel tank
  The higher of the 3 tubes that comes from the fuel pump
  The middle of the 3 tubes that comes from the fuel pump
  (I definitely know that the lower of the 3 pipes is the feed from the fuel tank)
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Also.....

• Where does the tube that comes from the front facing part of the right hand carb body end up (see second pic)?
  Ditto the tube that comes from the front facing part of the left hand carb body?
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Reason for asking is that the bike refuses to start after cutting out on me mid run last week and getting towed home. I've since taken the tank off cleaned it, stripped and reassembled the fuel tap, checked that the fuel pump delivers (comes from the top of the 3 feeds on the pump from what I can see) but still no joy starting. Then I noticed that there is no tube connected to the nipple that can be seen on the underside of the fuel tank and at the same time the tube that comes from the front facing part of the left hand carb body seems to be at a loose end.....? Haynes Manual not much use so stuck for inspiration.

Right Heelander your pictures don't seem to be loading but i'll have a go at answering best i can.

On the fuel pump you rightly say the lower one is from the fuel tap. the middle one is a vacuum pipe from the right hand inlet manifold, the section between the bottom of the carb and the cylinder head. the upper pipe is the fuel feed to the carbs. the pipe on the underside of the tank is a drain pipe and should route through between the back of the engine and the rear suspension.

From your description i'm guessing your talking about the pipes on the intake sections just below the carbs, one each cylinder. as i've said above one goes to the fuel pump. the other goes to the fuel tap. both are vacuum operated, this vacuum is drawn from the intakes.

If the pipe to the left hand intake is off, which operates the fuel tap, it won't be opening your fuel tap, ie no start. have you tried to start it in the PR or prime position. this bypasses the vacuum operate dvalve and allows a free flow staringht through the tap.

There is a pdf download of the TRX parts manual somewhere, i've got it and it shows good line drawing of all pipes and hoses, very useful

Thanks to rogerc and dixonj for helping me out. Rogerc your instructions worked a treat and normal service has resumed!

Feeling rather sheepish actually....reckon the reason the bike cut out in the first place was that it ran out of fuel. I then think I couldn't get it going again once back home because I missed the second vacuum tube going to the fuel tap which must have come off when I lifted the tank off and I never reconnected when reassembling everything

Every day's a school day.........