I rebuilt my engine recently.. , 020 over piston (basic, no extra compression), but did not adjust the carb. As soon as water gets near my muffler, the engine chokes-- then it'll rev back up, then it'll choke some more... could this be related to not adjusting the carb (ie too lean)?

I have checked all the hoses on the carb, the ignition wires, and even tested it with just the right rear of the ATV in the water... it chokes... if the left rear is in the water, it runs great.. thoughts?

I should probably mention ... 01 sp500ho.


thanks!

 

btt

 

Be sure that the vent hose for the carb is not sucking water up it.

 

Sounds to me like you have a steam problem. When water hits the muffler you get steam and it is probably getting drawn into your airbox. Mine had the same problem before I re-routed the intake to minimize the steam problem. I am not sure if it is actually getting drawn into the engine or whether it gets in the airbox and chokes the filter causing a rich condition for a split second. Never the less it does go away fast. It is not a sign of a lean condition, it is a sign of not being able to burn steam. Try blocking your intake from the muffler with something while still allowing flow to the airbox.

 

Interesting---- I'm confused though-- how does the steam from my muffler make its way to the top of my gas tank and into the airbox?

Or do you mean it backs up in the exhaust pipe itself and enters the combustion chamber from the exhaust valve? My intake is the factor snorkel in front of the seat--by the gas tank.

The vent hose is much higher than the muffler-- i had checked that.

thanks

 

It doesnt realy matter if you vent hose is higher than the muffler. Also even if your intake is up by the gas tank steam can still get up there. Your plastic will hold the steam under it till it escapes through gaps or your intake and vent hoses will suck it in.

 

okay-- i'll check that stuff next time i'm out.

I'm only surprised that it suddenly happened-- i have ridden in the mud and water a lot and to just start doing this is strange. How did you re-locate the intake?

thanks!

 

I'm not really sure what type of machine you have, so I don't know about the application. Are you sure it is steam off your muffler or is it your header pipe? Either way, the best thing to do is evaluate the design of your airbox and see what kind of changes you can make. There is a boat-load of ideas for this type of problem around here.

I took a 3" flexible elbow from my airbox and angled it upwards next to the steering column. It usually keeps the steam out. I will still get steam if i really try to drown it will snow. I also noticed that the steam problem for me is due to how fast I approach a snow drift or puddle if you take it slow with minimal splashing the steam problem decreases.

Also, make sure you tightened all of your hose clamps and bolts when you reassembled. Something is different about it you just have to find out what it is, I know this is obvious, but most times it really is that simple. Sometimes the most stupid things will bite you. It happens to everyone.

How does it run when you're not blazing through mus puddles? Any backfiring or missing throughout acceleration?

 

I will check the hose connections again -- it is an 02 sportsman 500ho. The factory instake is under the plastic above the seat/behind the gas tank.

The machine runs great outside of the mud/water-- no hesitation, no problems at all when running in the dirt or shallow mud. I do have to "pump" the gas some w/choke on to start it when cold, and when it is hot, it still requires a slight push of the throttle to get it started, but it idles smooth & consistenly.

 

I think maybe you should take the carb off and take it apart and clean it, also check the hose the carb goes on and be sure there is no cracks in it.