AP shaft seal on WR426.

Hi guys, I'm having problems keeping water out of the AP chamber.

Basically Its been such a wet winter here that the standing water is so much that I can't keep the water out of the carb.

I started out on sunday fine but after 3 hours and alot of puddles, it started coughing and spluttering and back firing.

Then it wouldn't idel or start.

Stripped the carb, cleaned it.

Went into my dealer, who told me about there being no seal ontop of the AP shaft, which on very wet rides allows water down into the chamber, screwing up carb. (This problem is adressed on the 450).

He surgested taking the shaft out and applying some silicone sealeant to the shaft, just enough so it seals but slides on twisting the throttle.

Has anybody else come across this or found a way to keep dirt and water out of the AP chamber?

Cheers, Rich.

The most common reason for contaminates in the carb is improper hose routing.

When you start or stall the motor, it sucks air (water/dirt) up the vent hoses into the carb.

You need to route all the vents above the carb.

Totally agree with Krannie.

My 400 used to play up in the wet until I moved 2 of the vent hoses up into the airbox. Used to stall after going through 1ft of water.

Never stalled since re-routing.

My AP boot is old and crappy and I use a piece off an old coat hanger as the pushrod (because I lost mine during trailside testing) which really wouldn't seal and I have never had water get into the AP.

Rode in the rain for 2hrs the other day, no problem.

Jetwash ... no problem.

Move those vent hoses


Yet another reason to NEVER talk to a mechanic at a dealer:


Cheers Guys, thanks for the feed back.

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