Drowned a WR400

Last weekends enduro ended up with a water logged WR, which obviously wouldn't start! Having emptied the exhaust, carb bowl and kicked over the engine without plug, the bike now runs OK. Have also changed the emulsion that was oil three times. Question is should I do anything else (top end off etc.?)

There are a few breather hoses that suck water up into the engine and carb.

Some of us WR450 owners have Tee'd off certain hoses and run the upper segments up to the airbox, or in my case, under the seat. I don't know which ones to Tee on the 400's. Do a forum search on the subject. May be the same ones.

I submarined my WR400 when it was brand new years ago. I did what you did, then changed the oil twice, and it's been running great ever since.

No worries mate!

Bryan in Denver...

There are a few breather hoses that suck water up into the engine and carb.

Some of us WR450 owners have Tee'd off certain hoses and run the upper segments up to the airbox, or in my case, under the seat. I don't know which ones to Tee on the 400's. Do a forum search on the subject. May be the same ones.

I keep seeing this whole deal about teeing off the hoses, any reason not to just run them straight to the airbox instead?

because it can still spit out oil from the breather and you dont want it going into the air box :cry:

Unless you overfill it we're only talking about a few drops here are'nt we? :cry:

I run my breather to the original designated place by yamaha e.g. on top of the boot between air filter and carb. I get a lot of oil in the boot from wheelies, but I do not see any problem with that :cry: :excuse me:

so what problems are you talking about? Especially if the breather is in the airbox???

While sitting on top of a dune with the engine breather hose less than an inch from the dry sand, engine idling, I noticed that the breather was blowing and sucking sand. When I removed the hose from the head that night the inside of the hose was coated with fine sand and dust. Is this OK? Not for me it isn't! I'd rather have a little oil showing up in the airbox low point any day. In my way of thinking 450cc of air has to come out that hose and then back in every revolution of the crank. That's a lot of sand. This breather belongs in the clean side of the air filter. Am I missing something here? Why was this not done by Yamaha? MMmm...

Regarding the carb vents, I would think they would need to exit at a point lower than where they origionate in order to drain any sloshed fuel. Also any fuel lying in a low point in the hose could cause pressure variations in the carb, leading to some problems. I'm leaving mine stock as there should be no sucking from these.

...Regarding the carb vents, I would think they would need to exit at a point lower than where they origionate in order to drain any sloshed fuel. Also any fuel lying in a low point in the hose could cause pressure variations in the carb, leading to some problems. I'm leaving mine stock as there should be no sucking from these.

I'm not 100% sure on this, as I've not been able to track a clear awnser on it, but I believe that the "vent" hoses on the carb will only pull air into the carb, therefore routhing them to the airbox is ideal, as it would keep water, sand, etc. out of the carb. I believe that there are seperate hoses for draining & overflow. Hopefully if this is incorrect someone in the know will come along & point it out. My question is if my asumptions are correct, which hoses are which? :cry:

I have my breather hose running to the airbox.

However there is one other sideaffect beside small drops of oil spitting into your airbox. If your bike is upside down for whatever reason (ie: you fall over on a steep hill) the bike will drain oil into your airbox. Enough oil actually that it will stall and prevent your bike from starting. (about 4 ounces from my experience)

Easy fix though. Clean air filter, top off oil, your good to go. :cry: And all this can be avoided if you pick up your bike right away, when it's upside down. :cry:

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