Hello, I am working on a 2000 Polaris Trailblazer 250cc. When I first got the 4 wheeler it was already not running. After cleaning the carburetor up, draining the gas, and installing a new ignition switch (due to it not having one) it would start up but was blowing gas out the back of the carburetor. I am only able to work on it over the weekend due to my schedule. It is now having more trouble starting. It will only start on the first pull for that weekend. This past weekend I took the carburetor off and sprayed some starter fluid in, it did start and blew it back out while it ran for the 1-2secs. Any suggestions would be helpful.

 

Do a compression check before you go any further. If it's under 100 psi probably time for a new top end.Spitting back through the back of the carb is one sign that compression may be low or crank seals may need to be replaced. If you do a top end I'd replace these cheap seals anyway.

 

Thanks for the information, I will let you know an update after the compression test.

 

I did a compression test it was topping at 92 psi

 

Time for a new top end at least. Pull the cylinder and have it measured as to the over size piston and rings needed. Wiseco is the best replacement piston around. This forged piston is a lot stronger than the oem cast piston. Also pull the rod up and down. If there is ANY movement(side to side play is ok),the bottom end needs to be split and a new rod kit,crank bearings and seals need to be installed.If you don't,the lower rod bearing can spit pieces up into the cylinder and take out a new piston and fresh bore job. Just a reminder to really check this out. Had too many people that this happened to over the years.