Hey guys I'm new to the site, and I would like to start off by saying this seems like a really friendly message board to be a part of. I'm a newbee to the atv world and I just recently bought my first atv. The machine is a 1995 Polaris 300 4x4. I bought it last week and only got to take it out 3 times before experiencing some problems. The guy I bought it from rebuilt the engine and it only had 1 hour of ride time on it when I got it. He showed me pictures of the rebuild and receipts for the parts, so I know he isn't full of it. The carb was cleaned, and it ran pretty good when I got it. It did seem like the idle was kinda low though. When I parked it yesterday it started backfiring and bogging when I gave it throttle. It will idle for a while, but it does eventually stall. I pulled the plug and it was wet. Did I buy a lemon or could this be an easy fix? I'm kinda bummed out because my wife and I were planning a riding trip this weekend that is going to have to be postponed. Any help that you guys might have would be greatly appreciated. Thanks a lot.
-Elliot

 

Sounds like an issue for old polaris tech. He's really good wiith that stuff. You could have any number of problems. The carb may not be adjusted right and/or it may not be getting enough air. Would explain why it's running rich and bogging/stalling. Best bet is to get your hands on a manual so you can be sure the carb is set right, make sure you have good air flow, and make sure there is good spark. If you have those then it is time to dig deeper and start checking valve clearance, compression, etc. Hopefully it's an easy fix and you're riding with your honey soon.

 

welcome to the forum. i'm pretty sure that is a 2 stroke 300 so no valves to worry about. make sure the etc is set right w/ about 1/8" gap(this is the gap between the stop and throttle)so the throttle override is not kicking in. if it is floooding(too much gas)maybe check the carb float for being right highth. did this guy bore out the cylinder and put new rings when he rebuilt the engine?? wondering what the compression is as well as mentioned. you need to start some where and the carb is the easiest place. also make sur the choke is not sticking which will give way too much gas as it is a richen port that lets gas pour right in if the plunger is not all the way closed. keep us posted.

 

Good catch Sten-almost forgot about those old 2-strokes.

 

Yes, the machine is a 2 stroke. The previous owner honed the cylinder and installed all new wiesco parts including rings. I don't have a compression tester but when you pull start it, it does seem to have a lot of compression. I'm going to try and track down the choke on it. I was a mechanic for a few years, but never once have I messed with a carb lol. Everything I have ever worked on have been fuel injected 4 strokes, so bare with me. I guess you could say I'm a carb tard. Thanks for the quick responses guys.

 

I went out and played with the choke for a while and it didn't have an affect on how terrible this thing is running. I looked at the etc but I'm a little unsure of where to make the adjustment. There is a little screw that goes through what looks to be a limiter. That adjustment is maxed out the whole way and there seems to be about 1/4-3/8" of play between throttle tension and stop.

 

Wow, do I feel stupid. I just dropped a new plug in it and now it runs like a dream! Thanks folks. BTW nice looking mustang Sten.

 

thanks. btw, we have all been there,done that lol