I purchased a pwk kehin carb pn 39pwk400tm and a velocity excellorator pn vepwk39 from hpd inc. I am having problems with the carb draining itself. After 2 days when I go to start my 2002 scrambler 2 stroke it will not start and I have to pour a small amount of fuel inside the carb from the top. I noticed that there was a valve inline with the overflow line on the stock carb. Is this a check valve and do I have to install it inline with the overflow line on the kehin? Also I noticed that when the quad is running there is a constant flow of fuel (not much) coming out of overflow line. To stop the draining I moved the end of the line above the carb so it would not drain out. This I’m sure doesn’t help the carb’s performance?

Also I was wondering what jet is called for for 2820 ft and 14 deg f, 50 deg f, 86 deg f ?

 

hey have same set up on my 99 scrambler no trouble like that on the pwk sorry? but there is or was a black wire off the cdi that gets rid of all safty features like your overide

 

so i just have to cut that wire?

 

Sounds like the needle and seat is not shutting off the fuel.

 

thats whats wierd. if it isnt shutting off the fuel i should have no problem starting it after not using it for a couple of days. the fuel coming out of the overflow while it is running indicates that the needle isn't shutting off the fuel from coming into the float bowl. on the other hand when it wont start it seems like not enough fuel is coming into the float bowl. i took the carb apart and checked that the needle valve was functioning. everything seemed fine.

 

Alot of times the end of the plunger will wear a small groove into it and just this small groove will not allow it to seal off.

 

this carb has about 2 hrs of use on it

 

No probs here. But they did send jets that were waaay to rich. I had to buy some smaller jets at a local dealer.

 

If you got it from HPD then I would call and ask them what's up? I got mine from them and as soon as I put it on fuel just started to pour out. I had to mess with the float level to get it to not pour out. I had a hell of a time with it for a day or two then never had a problem since.

Have you checked to see if the starting circuit is plugged somehow? I know it's new but stranger things have probably happened.