engine dying after water crossing

[Johnnyboy]

I am wondernig if any of you have this problem or a remedy. I have an 83 kdx 200 that will almost always die after a water crossing. I have a uni-filter and stock air box with all the water and mud guards in place but it will still die. It doesn't matter if the air filter is freshly cleaned or really dirty or even if it is a shaoolw water crossing that doesnt even come up to the engine. Some of my carb and engine breather tubes are getting a little short... could this be the problem? I kind of doubt it. What I think is happening is the water hits the engine and creates a bunch of steam which chokes out the engine. It takes about 10 or 15 kicks and then it runs bad for 3 secs and then I'm off like it never happened. Anyone have suggestions on how to fix this? Or do you think it may be something else?

 

[dirt bike dave]

If the water is not getting anywhere near the carb and air filter, it is probably your ignition. The likely culprit is the cover over the flywheel on the left side of the engine. Make sure both surfaces of the cover are flat, and try sealing with silicon sealant. Check your other electrical connections while you are at it - it sounds like moisture is splashing onto something.

 

[91KDX]

I had the same problem with my 91 KDX, I lost an egg hunt because of it (no biggy). Every time I went though water it would quit, so I took my bike home, and sealed all of the wires up. The rubber plug in the cover of my flywheel came out and the wires going to my head light were exposed and were getting wet. What you can do if your on the trail and go through a stream or river is spray WD-40 or some oil based spray on the out side of your spark plug and any other electrical wires. The oil is water resistant so it coats the wire preventing it to ground out. Also try and keep the splash down...

 

[David Trustrum]

In addition a decent plug cap is a good idea. NGK make one for jetskis.

 

[Gates]

Check you air boot and box for leaks. It only takes some vapor being sucked into the carb to cause those symtems. If any air is bypassing the filter to the carb it will die. I know, I did not tighten my air boot once and we checked everything about the ignition. Finally we tighted the boot and all was OK. It does sound more like a wire problem though.

 

[MX175]

All good plans, but make sure you don't have a crack or something in the CDI unit or coil under the gas tank. Both of these can cause problems. But if I was a betting man, I'd look at the flywheel cover and the rubber plug first.

By the way Johnnyboy, I am visiting some friends in Boulder this June. Could you e-mail me directly with suggested areas to ride to hit some high country, preferrably single track rather than 4-wheel drive. We are headed to the Rampart Range area, SW of Denver.

 

[Canadian Dave]

Good advice. I'd also consider installing T vents on your carb just in case the carb is drawing water into the float bowl through the vent tubes. My friends KLX300 did this when ever is saw water. They are easy to make yourself just head down to the local hardware store and pick up some appropriate tubing and T or Y shaped connectors and splice them into your existing vent lines. Run the new line up near your airbox and let the original lines exit near the bottom of the bike as they originally did. This will allow air to be drawn from either end of the tube and prevent water from being drawn up into the carb. If you need more detail than that just say the word.

David

 

[Johnnyboy]

Thanks guys those are good suggestions I'm inclined to think it may be water getting drawn into the float bowl or a leak around the stator. Good suggestions.

 

[Johnnyboy]

MX175 I cant seem to get your email, it's blocking me. Can you post it or send me an email?

 

[John Harris]

The above tips are all good and probably will solve the problem. However, if I understand your KDX is one of the good ole air cooled ones. I always had difficulty with keeping an air cooled 2 stroke running after plenty of cold water--seems like cylinder just temperature shrunk around a hot piston and things just did not do right until cylinder warmed up again. Keep it above an idle while in the water, even if you have to use the clutch!

 

[whazup]

we had that problem on all the air cooled kdx 200's and it would happen just from a puddle we would loose spark. we cured the problem with a malcom smith red rubber plug cap, they do not carry the brand anymore. so a good plug cap would be a good starting point.