Water in airbox and through the motor...re-routing carby vent lines??

pdee4t
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10/26/2014 5:21am Edited Date/Time 10/27/2014 8:54am
Hi everyone.
Went riding today, ended up having to ride through some water ruts. Didn't realise how deep 1 of them was until I actually rode through it. It was almost to the top of my front wheel.
Anyway, the bike started blowing white smoke/steam, the oil became all bubbly and thin and wattery(wasn't milky but just looked very thin like it was water based), as well as the bike not wanting to start back up for a while(out of the water) and the inside of the muffler was all wet/wattery too.
(Its not a blown head gasket as the bike just had a rebuild and I also didn't lose any coolant).

Anyway, I brought it home, took the air filter out and checked inside the air box and found a little puddle of wet brown water inside the air box, just below the carby intake boot.
EVERYTHING else around the filter, including the filter itself was clean as a whistle, dry and still had air filter oil on it and the sealing surface where the filter seals against was not muddy or wet at all, just had rim grease on it, as it usually does....so the water didn't get in externally from outside the air box.

It got sucked up through the carby vent hoses that hang out the bottom of the bike(too much water going in at a fast rate), because that's the only other way it could've made its way into my air box, and through my motor then out my exhaust.
The bike did end up starting back up and running in the end, it wasn't hydraulic locked or anything, so I rode it back to the car even if the oil had a bit of water in it, and it wasn't too much water, but was enough to get into my air box.

Ive already done a few oil drains to get all, if not most the water out but i'm just wondering, what's the best way to re-route the carby vent hoses?? I have read the Dave Hopkins Carb Setup 101 method, wondering if there's other methods people use to re-route em? his method still has 1 hose facing below the bike.

It's a KTM 450 EXC 2004 model.
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smoothies862
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Fantasy
745th
10/26/2014 5:47am
try ktm talk. those guys have all the good tips for your bike. someone may have some good info here too,but that site is pure pumpkin.
hillbilly
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10/26/2014 7:43am
There is no vacum on those hoses hanging out the bottom.

You sure it didnt go in the filter, if you rode it then hauled home things cpuld dry out from engine heat.

There is a bowl vent on the back of the carb that would let water into the float bowl,same with those carb hoses,you should have muddy water in the bowl and it aint running right it that is the case. Water and jets dont mix.

Could the water went in the hot start opening?

And,if you had enuff water in the cylinder to contaminate the oil it would be blowing out the exhaust ,it takes a lot to bypass rings. If any water had been in the oil it would been milky,it was thin because of heat I'd have to believe.
pdee4t
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10/26/2014 8:55am Edited Date/Time 10/26/2014 9:04am
the water wasn't up to the level of the air box though. the entire air box is clean and the air box cover itself is clean-ish. no signs of mud from the water puddle on it.
so it had to of come up through the vent hoses somehow, the sealing surface for the air filter was clean as a whistle, no mud or dirt or anything. so I doubt it would've come from the air box after considering everything I just mentioned.
although the hoses don't create vacuum, I have heard of cases before where water creeps it's way up through them, especially considering I was in the water for a good 10-15 seconds before I got out of it.

the oil was a very dark brown colour(same colour as the water in the puddle). how could it of gone through the airbox and filter externally, when the air box and side covers are almost squeaky clean...doesn't make sense if that were the case.

there was only a little bit of water, so that's why the oil wasn't milky.
I also have a hot start lever on my carby that I put on, so it had no chance of getting in through there.
the exhaust was blowing very white smoke, like steam, for about 10 minutes.
pdee4t
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10/26/2014 8:57am
as you can see in the picture, that's all there was inside the air box. around the air filter sealing surface...it's all clean(ie: no mud or dirt)...just rim grease.



The Shop

lumpy790
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York, SC US
10/26/2014 6:09pm
not possible for water to enter the air boot via vent hoses. Water probably sucked straight through the air filter.
pdee4t
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10/26/2014 8:20pm
It is very possible for water to suck up through the carby vents. Do a search and see how many others it's happened to.
pdee4t
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10/27/2014 12:21am
on closer inspection, im just wondering if the fuel somehow mixed with the oil, causing the exhaust to blow out white smoke.
reason why i think this is because, after that water puddle, the bike didn't stall. I kept riding for 5 or so minutes until me and my mate stacked on a hill and the bike was on it's side for 5-6 minutes while helping him pick up his bike and roll it back down the hill(his bike has no side stand). When I got back to my bike, fuel was seeping out of the top of the fuel tank, where the cap sits, even though the fuel switch was turned off.
wondering if it would be that the bike was on it's side for a while, so the engine oil went up through the crank breather hose that goes into the carby intake funnel, then mixed it all together and out through the air box via gravity or something along those lines?

the fuel I used was yellow in color, the oil I use is like a light brown color, that's the same color that was in my air box.
the fact that it ran for 5 minutes without any effect probably means it wasn't actually water inside there?
10/27/2014 12:23am
The water that's in your engine more than likely was sucked up by the crankcase vent hose. When the piston moves upwards it creates a vacuum in the crankcase just like it does when its moving down the cylinder pulling in air through the intake.

If you put your finger over the crankcase vent hose you will notice it pulls your finger, then blows it off. Given enough time submerged in water, and a couple hundred or thousand rpm, water will make its way up this hose and into your precious engine.

Now for the water in the air boot. You either failed to allow the filter to dry completely between washing and re-oiling, or you over oiled the filter and it has passed through taking some fine dust with it.
pdee4t
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10/27/2014 12:36am
the filter was completely rung out and dry as I always do.
how about my theory? is that possible?

the bike was not submerged in water for a long period of time and as I said, I rode for another 5 minutes straight after it.
10/27/2014 2:32am Edited Date/Time 10/27/2014 3:00am
5 or 6 years ago I had something similar happen to me. I clipped a diagonal log that was lurking under the surface of a water crossing and took a trip over the bars. My bike and I both went for a quick swim. Once I got the bike out and dumped my boots I tried to start the sucker. It didn't fire so I pulled the pipe off to check for water and that was dry. Then I looked in the air boot and saw exactly what it's in your picture. Turns out the water went straight through the filter and into the crank. The carb had water in it too, which I assumed leaked down through the jets and passages as it passed through the carb. The trans oil was contaminated as well, which I later traced to a poor seal on the power valve linkage cover. I was using a bio-degradable filter oil at the time, switched back to BelRay after a couple at home "scientific" trials involving buckets. Good stuff, it's stickier than Ron Jeremy's couch. Just sharing my experience with a soggy bike, your mileage may vary.
10/27/2014 4:05am
Just read through your thread again and noticed your ride is a four stroke. Disregard my previous post as it is more two stroke related. With the bike was on its side the float would not work properly and fuel could have been running into the cylinder and bled past the piston thinning out the oil. Did the oil smell like gas? If the filter element got a bit wet the moisture could have been sucked through and caused the white smoke and hard starting due to decreased air flow. It would dry out pretty quick with the amount of air those things pump.
10/27/2014 5:41am
Not to be a smart ass, but I think the best solution is to make sure that your front tire is never completely below water. I've been riding for 39 years and this was only a problem for me once. I learned that the edge of a lake might be shallow but it could get deep fast. Then it never happened again.
pdee4t
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10/27/2014 5:53am Edited Date/Time 10/27/2014 5:58am
Just read through your thread again and noticed your ride is a four stroke. Disregard my previous post as it is more two stroke related. With...
Just read through your thread again and noticed your ride is a four stroke. Disregard my previous post as it is more two stroke related. With the bike was on its side the float would not work properly and fuel could have been running into the cylinder and bled past the piston thinning out the oil. Did the oil smell like gas? If the filter element got a bit wet the moisture could have been sucked through and caused the white smoke and hard starting due to decreased air flow. It would dry out pretty quick with the amount of air those things pump.
don't really know what it smelt like, didn't really smell it.
you mean if the filter element got a bit wet from the fuel that bled passed the piston?
is there a way the fuel could've somehow gotten into the filter/passed the intake by laying on its side?

also, the bigger question is how long does it typically take for water in the oil to start corroding things, like bearings, etc? I am wondering if I should take the motor apart to inspect because I rode it for a bit like that and left the wattery oil in the motor for awhile(just under 24 hours).
pdee4t
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10/27/2014 8:20am Edited Date/Time 10/27/2014 8:21am
The water that's in your engine more than likely was sucked up by the crankcase vent hose. When the piston moves upwards it creates a vacuum...
The water that's in your engine more than likely was sucked up by the crankcase vent hose. When the piston moves upwards it creates a vacuum in the crankcase just like it does when its moving down the cylinder pulling in air through the intake.

If you put your finger over the crankcase vent hose you will notice it pulls your finger, then blows it off. Given enough time submerged in water, and a couple hundred or thousand rpm, water will make its way up this hose and into your precious engine.

Now for the water in the air boot. You either failed to allow the filter to dry completely between washing and re-oiling, or you over oiled the filter and it has passed through taking some fine dust with it.
I am considering re routing the crankcase breather hose and putting a filter in it but how then would the air get into it if the filter is blocking up the open end of the hose?

At the moment one side connects to my crankcase and the other side connects to the carby intake funnel(there's a hole in the intake funnel it connects to), which allows air in.
Moto75
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10/27/2014 8:54am
I would guess there was enough water in the airbox for the filter to suck some in. With it being oily, it would not hold water & any water that got on the filter would dry out quickly with running it. The vent houses should see no vacuum. All air is designed to flow through the venturi. Air passing through the vent lines would 1) Not be filtered. 2) Cause a lean condition since it's not flowing through the venturi.. - Your bike would not run right.

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