Went swimming.....engine missing bad.

Hey guys, I need some help here. I'm seriously bummed :).

I just got back from riding and was having a ball when I hit a serious "puddle" (it was drippin off my goggles). I stopped the bike to reconnect my odometer cable (came unscrewed up top). I started the beast with no problem, but when I went to go up a hill, the engine was missing badly (sputter, sputter, pop,pop). Major loss of power. I ran it about 20 more minutes and still had the same problems. 1st and 2nd gear..no noticeable change, shift to 3rd, mushy throttle and misfiring.

I'm headed to the garage to change the oil to see what it looks like. Any input would be appreciated.

Sounds like you may have gotten water in the

carb or in the tank or in the inside of your

ignition cover.



"01" KTM 520 EXC

Mesa, AZ

Sounds like the old "water in the float bowl" trick to me. I would try draining the carb before doing anything else…

okay, changed the oil and it looks okay. Little whitish on top as it drained.

Ron, help a guy out. How might I drain the carb. A big thank you in advance :).

A bit of an explanation for water in the tank or floatbowl acting up only sometimes is that when you open the throttle, gas comes up an out the main jet, which draws from right near the bottom of the float bowl. Hence at part throttle it may be ok, but when you hammer it it gets a big gulp of water. Then the water bits occasionally come down the gas line from where they settled in the bottom of the tank, and settle in the bottom of the float bowl, ready to cause more trouble. After you've de-watered the tank and bowl, add a bit of alcohol to your full tank of gas to get the rest.

Do these bikes have a drain on the float bowl? I'm at work so I can't run out to the garage and look. My XR400 needed a 12mm wrench to loosen the float bowl drain plug. I used to carry one in my fanny pack for a deep creek crossing that managed to fill the bowl with water every time. All I had to do was turn off the fuel, remove the drain plug and watch water spill on the trail. Replace the plug, turn on the fuel and away I went.

I hope this helps...

Yep, there is a drain. Just looked at HLS.

Mojo - drain that sucker! :)

Yes, they have a drain. Not sure if it's a drain, but it'll get the fuel out :) It would be the same bolt you remove to access the main jet. I'm not sure what wrench size, I'm to busy reading ThumperTalk :D :D



97 KDX220, 86 TTR225, 99 WR400f, WR timing, throttle stop trimmed, air box lid removed, White Bros head pipe, silencer and air filter. De-octopussed. Works frame guards and Thumper Rad Guards, Scotts steering damper. Odometer and headlight removed. Moose hand and mud guards. YZ stock tank, IMS seat and number plate. Renthal Jimmy Button "highs" and Renthal Soft half waffle grips. AMA, SETRA, Happy Ramblers MXC.

Ron....HLS?? I'm an idiot and need pictures :).

Where can I see what you looked at?

BTW - Here is the creek in the fall. It's much deeper in the spring!


Mojo - It's the bolt looking thing on the very bottom of the carb. Go look at http://www.hlsm.com

Sorry about being vague.


I drained the carb twice and it seems to be improving. I don't want to tick off my neighbors too much by going up and down the street.

Thank you for taking the time to help with my little emergency. You are what makes this such a great place. If your ever up north, or I'm that way, I owe you a cold one.


(Nice picture, that's about how deep it was for me).


Two remove the float boal bolt, you will need a 14mm. We do a lot of main jet changing here in the altitude.

Actually Dougie, it's a 18mm bolt (at least on mine). Thanks for the input. I think this one is cured.

Couldn't you just turn off the gas and lay the bike on it's side to drain the bowl?

I've never been able to get all the water out that way. Usually to fush it out I'll turn the fuel line on for a second or two while the bolt is out, but that's not a good idea. The best thing to do is tee the vent tubes so water wont get in the float bowl in the first place. Have to admit I have not done this to my WR yet and have stalled it in that crossing pictured above.

Going there on Friday the 13th but it may not be passable this time of year. I've ridden my old XR600 through there when it was so deep that the water came up over the seat and the Yosh exhaust was under water! Sounded like a big bad motor boat. I spent a lot of time waterproofing that bike, it was amazing.

The 3mm allen screw on the bottom left portion of the carb is the drain screw. Just trace the hose on the bottom of the carb down, and put some tape on it to identify it. Drain it into a can and dispose or properly.

If you take the bolt out, the gas will pour all over the place. What a mess.

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