WR deep water crossing carb vents redirect

Hi everybody!

We just got back from the tough trip (400 miles in two days) through the most wild and ndevelopped terrain. While crossing the rivers, depth up to the 3'2" almost everybody had the engine full of water :thumbsup:. Another problem was water getting into the carb through the vent hoses..

I remember we had a deep discussion about this issie some time ago, but I did not pay much attention then, now I ask your help on this issue.

What should be done on my WR450F to improve performance and avoid water suck while river crossings!!

Another question is what might be the potential danger if the water finally gets into the engine and mixes with the oil ( I run on Motul 300V factory line Syn)???

Please help.

Here is some advice grabbed from other posts.

What you are experiencig is a breather resriction such as would happen with your gas tank if you were to plug off the vent tube on the gas cap.The gas won't flow out to the carb.The same happens when you ride into deep water that closes off air flow into the floatbowl.This allows the gas to flow from the floatbowl out though all the jets. Your WR400 has four breather tubes that run from a tee conector on both sides at the top back of the carberator and run down between the back of the engine and shock.Try pulling the tubes that come off the top of the tee and run them up under the seat along the top edge of the air filter box and tie them off to the frame.This fixed my problem on my yz400f. Dan Lombardy Grapeview Wa.


I, too have routed my carb vent tubes for deep water. But I didn't use a tee except on the float bowl vent tube. On the earlier model carbs, there are tees built into the carb so that four hoses are routed to the bottom of the bike. I took one hose from each tee and routed them to the airbox. I teed off the float bowl vent tube, routing one hose up and one down. On the newer carb models that's not necessary, but I think you still have four hoses, two on each side of the carb, routed to the bottom of the bike. You can route one hose from each side up to the airbox and it will accomplish the same thing as teeing off the lines. I've got a friend with an '01 model and that's what he did after he rode through deep water and had bad stalling problems while mine cruised right through. Now he can tackle deep water without stalling, too.

Otherwise do a search of the WR450 forum for "carbs water". You should be able to find an answer.

If you think you have water in your engine, CHANGE YOUR OIL IMMEDIATELY. :thumbsup:

This has pictures of how to "de-octupus" the WR250 and applies to 450


has been very helpful to me

DOHHH I posted in wrong forum

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