Hello

Just picked up a 1996 Polaris Trail Boss from a friend of mine he was messing with the carb trying to get it to run.

It seams to start fine but will not idle and seams to flood out. It don't seam to matter what you do with the idle or mixture screws any ideas? Do the O-rings behind the intake boot go bad? That I would think would give me a lean condition. Could the Float be set wrong and gas be getting by the needle and seat? The only other thought I just had was maybe the Air cleaner is plugged have not pulled it yet.

The thing is when he bought it it ran fin it sat then the next time he went to start it it started acting up fouling plugs etc so that is why he rebuilt the carb and started fiddling with it.

I know the Compression is at least 100 PSI when we checked it but cant remember the exact number.

The carb is a Mikuni (SP?) I think it is a 30mm if I remember correctly. I am in Wisconsin.

Oh it seams to load up to when letting up on the throttle.

 

i would look at the intake boot itself..they have a habit of cracking. pull it off and check it over real good. pull the intake down/up/left/right. check the airbox boot too...it could have a crack in it. after that i would start looking at the crankshaft seals.

 

check the air filter fr sure as well as if the float isnt set right it would be flooding it out even w/ it setting there. check to make sure the choke plunger is shutting all the way as it would be letting more gas then normal pour in. imo.

 

Where in WI? Yep it should be a 30mm. Take your time when cleaning the carb, do a good job.

 

I am in Green Bay

ok pulled a little apart last night. Not down to the intake boot yet though.

I know the boot from the Air Cleaner to the Carb is cracked for sure that one I need to replace it was siliconed to try and fix it I noticed. The Air filter smells like gas and the inside the carb looked wet and it has not ran in 24 hrs.

The Carb was completely torn apart about a month or two ago and cleaned inside and out and a complete rebuild kit with a new choke installed.

I also notice two clear lines in there one just goes no place and is connected to the carb. The other goes to a "T" that looks like it goes to the crankcase and the carb and the other end goes to a VAC I am guessing check valve and then to no place. Are these anything. I have a pic if I figured out how to post it correctly.

When I tried to start it last night it sounded like a shot gun going off from being loaded up.

 

those lines your talking about are just vent/overflow lines. check the float level since everything was just redone in the carb...the float should sit level with the gasket matting surface when the carb is upside down.

 

those vent lines run up to the frame right where the seat sits there should be a couple of holes in the top of the frame where them vent lines just stick in...atleast thats where they are on my 96 400. and like statedcheck the float setting.

 

Thanks guys I will take a look at that Sunday afternoon and let you know what I find. Unfortunately that is the first chance I am going to have to look at it more.

 

Somthing else to keep in mind - 2 strokes are not meant to sit and idle. You can start them and let them warm up for 30 seconds to a minute, but much longer than that will give you loading and fouling issues.

If you have not already done so, replace the jets in the carb with the OEM sizes (Ask your dealer). Replace the main jet and the pilot jet with new ones. If the quad has sat like you said, these can be very difficult to clean out just right. It is easier to just replace them.

 

I will look what jet is in it could be the winter jet I know he tried that one.

But as idle goes I can't even get 2 seconds from it that is how bad it is. I am starting to think it is a combination of things so I am going to put in a new air filter and set the carb back to factory that is supposed to be good I think from 40 to 80 Deg F.