Cutting out water crossing

Has anyone experienced their bike cutting out when crossing water that's about 1.5'- 2' deep? is there a fix or something that can be done to corect this problem. I checked my air cleaner after the ride and there didn't seem to be any evidence of water in the air cleaner. Someone said the vent tubes. This was on the Mystery 250 in Nevada what a great ride. Thanks for any help

Mike Kaveney

I have noticed the same thing when crossing water.

Once, I stalled the bike on a tree log in water that was high enough to submerge the breather hose. I noticed a gurgling sound as I was kicking to start it. I kicked it a lot before I got it running. At the end of the day, I drained the oil and it was white and milky in color. I assumed it was the breather hose sucking in water.

It is the vent tubes on the side of the carbs that is causing the stalling.

If you put a "T" fitting off the carb and run a line up and into the airbox from each side of the carb this will help alot. You can get the "T" and hose at a auto store. Or PC racing and Pro Circit make a vent tube "t" kit with a filter that mounts in the airbox that the vent lines feed into.

When the vent tubes go under water it creates a vacume or something and the carb cant breath. Heck Im not really sure what happens but stalling is the result.

Actually you don't have to "T" the lines. The carb has 2 vent hoses coming off of either side of the carb for a total of 4. If you take 1 from each side and run them into your air box. 2 in airbox and 2 hanging down. You will not have the bog problem.

I asked the same question two weeks ago & was told to put in a T piece on each of the two breather hoses coming from the carby. Also put a T piece in the engine breather hose aswell because the motor WILL suck water into the top end through this hose. This is the hose that comes from the tappet cover & runs down to near the gearlever.

Does this apply to a 2001 wr426? I have no problem with it stalling in water... My brother also has a 2001 wr250 and it does not stall in water?

OK...here we go...We have had numerous discussions concerning this issue during the past year or so. The problem occures when water gets inside the left side housing where all the electrical components (Generator) are. Even just a little water causes a disruption which causes the bike to sputter and miss until the heat of the engine evaporates the water. It's getting in through one (or Both) of the inspection plugs. After numerous rides and normal heating and cooling the plugs will work their way loose and there is just enough room between the threads to cause this problem. Many of us have applied a thin coat of silicone to the threads and have not had anymore problems.

DEAN400....Do NOT under any circumstances attempt to start your bike with the breather hose submerged. The pipe maintains positive crankcase ventilation, when running it has a constant exhaust pressure, however when you kick the bike it initially sucks air in and if it is submerged it turns into a drinking straw filling your engine with water.

This T fitting issue has been debated since this board came online. No one has every difinitively proved it was better than the way it has been routed from the factory. Some like it some don't , but the majority of us have just left it alone.

Good bike maintenance will for the most part will help you avoid many of these problems. Keep an eye on you fasteners ,electrical components and Oil changes and Ol'Blue will never leave you stranded.

Good Luck...

Bonzai :)

Yamakazi, If you are getting water in the generator side of the case you have bigger problems. the Ignition generator is submersed in oil. How a little water will affect this is beyond me. I just installed a wr stator last night on my yz400 and unless there is something wrong with my bike the entire lh case is filled with oil including the generator. This is not like my yz250 2 stroke were the stator was dry all the time. If you are gettin water in the cases I doubt it is affecting the generator which is designed to work submersed in oil.

I have had great success with the rerouting of the vent tubes up to the air box. Was riding with a guy last year on a DRZ that kept dying in the water. We routed just 1 of the breather tubes up to the air box and no more problem. The problem develops with all carbs, 2 stroke and 4. When crossing a water crossing the carb breather tubes hang down into the water. When the cool water hits the carb it causes a pressure difference with the cooling air in the carb. The vent tubes are underwater so can not equalize the pressure, the carb can not then feed fuel/air to the engine in the proper ratio and the engine dies.

The other issue of a electical problem may be something else, but if the bike runs proper after being removed from the water try this. Its free and is a proven trick with off road racers around the country.

Route the 2 hoses to your air box, either via a "T" connection, or just pulling the two hoses up and terminating them in the air box....problem fixed. Worked magic on my bike, I couldn't even get my bike to stall, tipped over on it's right side, muffler submerged, in the middle of Jenny Creek, just sat there and idled :):D !! I was laughing my a$$ off at that sight!

Dodger :D:D

Hey guys thanks for the reply's. looks like I will try to vent the two tubes on the carb

Mike Kaveney 99 WR

endurodog knows the way, the rest are talking in brail, the engine breather tube wont suck, its a breather that releaves crank case pressure!!!

Originally posted by YAMAKAZE:

No one has every difinitively proved it was better than the way it has been routed from the factory. Some like it some don't , but the majority of us have just left it alone.

Bonzai :)

Not sure what kind of proof you want/need, but my 01 426 wouldn't cross any water over about 12" deep. I "T" fitted two of the tubes and it's now a submarine. I crossed *many* streams during last years Colorado 500 and the bike never faultered.

Endurodog also mentioned the fix above. We were told this by Team Green mechanics on the same ride.

Do what you want but there is no downside with t-venting the breather hoses..

Merf

I'm thinking that if you go to a junkyard and buy an old Hummer exhaust system...rig it onto the stock exhaust header...and then run the two vent hoses off of the carb up your new exhaust stack, you can cross 8' deep water.

Just my $0.02... :)

Of course, there's no water here in CO whatsoever to cross...so I cannot prove my theory personally. Someone want to try this? :D

Merfman, according to TT lore the breather is exactly what it is called....a breather, in......out.....in......out..... So when the engine is running it vents slightly. However when the engine is stopped and you try to restart, the breather 'sucks'. So if the hose end is under water when you kick, you'll get a belly full of water, mid, grit etc.

Merfman...Check your PM....

Bonzai :)

Originally posted by The Missile:

Merfman, according to TT lore the breather is exactly what it is called....a breather, in......out.....in......out..... So when the engine is running it vents slightly. However when the engine is stopped and you try to restart, the breather 'sucks'. So if the hose end is under water when you kick, you'll get a belly full of water, mid, grit etc.

???? where did I say anything to the contrary? I'm just saying that IF you vent the hoses and one end becomes clogged (blocked by water) that the other end (the one in the airbox) will allows the carb to breathe. Is all.

I'll try to get some pix soon of my mod.

Merf

Originally posted by blue beast wins:

the engine breather tube wont suck, its a breather that releaves crank case pressure!!!

Oh yes it will. It has been proven many many times by myself and others. The hose will definitely suck up water if you try to kickstart with it submerged.

Reroute two of the carb vents, and reroute the breather and you will be set for water crossings. Don't forget to grease your swingarm - the water will wreak havoc on the bearings in there.

You may have a submarine there.

is your kick starter under water too??

[ June 17, 2002: Message edited by: blue beast wins ]

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