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Discussion Starter #1
I recently bought a 2001 trail boss 325 owner said it had been sitting a while but ran. I noticed the choke had to pulled out for it to run. I drove it and the quad studdered. I figured the carb was dirty. So I bought a new carb for $40 off ebay. I did it for my Sportsman and its run perfectly. However I put this carb in and the fuel runs right through the carb and out the bowl but the choke doesn't need to be pulled. Also the idle is extremely high. I adjusted the idle but nothing helps. I think I got a bad carb. Also I noticed that the shutoff valve was. Bypassed. Would this cause too much fuel going into the carb. Also no fuel filter
 

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I am glad to hear that one of the cheap knock off carbs did work. I had to figure they did for someone but we only hear about the bad experiences here. As for you problem, rebuild the original carb. The new one is leaking through the needle/seat. Could be just a stuck float but you have to take it apart to find out. The high idle is probably just the throttle cable. Pop the top off the throttle housing and adjust the cable to make the etc switch right. The fuel shut off bypassed will not cause the leak.


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I would also wonder if the previous owner bypassed the fuel pump. You can still get the shut off from Polaris too. The pump is above the right front wheel. 3 tubes to and from it


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Discussion Starter #4
I figured I did get lucky. I do plan on cleaning or rebuilding the carb. Thanks for the info about the bypass. I just wasnt sure
 

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I am glad to hear that one of the cheap knock off carbs did work. I had to figure they did for someone but we only hear about the bad experiences here. As for you problem, rebuild the original carb. The new one is leaking through the needle/seat. Could be just a stuck float but you have to take it apart to find out. The high idle is probably just the throttle cable. Pop the top off the throttle housing and adjust the cable to make the etc switch right. The fuel shut off bypassed will not cause the leak.


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For the record - I have installed many Chinese copy carbs with 99% success, but I buy only from established reliable sources and only 10% didn't need to be tweaked to run right. The one 'knock off' I installed that could not be made to operate was replaced by the distributor and the replacement functioned as expected. I have even removed owner installed 'knock offs' and installed my own 'knock off' in order to make a Polaris 330 run right. I tried to make the owner installed carb work and gave up before putting more into it than it was worth. I have installed the 'knock offs' on Honda's, Suzuki's, Kawasaki's, Yamaha's, Arctic Cat's and Polaris's - I have installed them on the Chinese 'knock off' engines as well, but if it is a knock off engine with a knock off carb, then is a different knock off carb an upgrade or downgrade?

I look at carbs differently than most people - a carb is just a mixer - it mixes fuel with air - it doesn't make any difference who made it (as long as it is of quality construction) or what name is on it.

Just to prove the point, I installed a Kun Fu carb on an XR200 Honda and raced it in a hare scramble race. I finished the race in the top three which is where I expect I would have finished if I had the OEM carb on the bike. The carb was not a plug-n-play installation, it required rejetting to perform acceptably and the jets were not over the counter replacements - I had to re-thread the carb to take the jet I wanted to install and I had to re-drill a passage in the carb body to flow the amount of air that I determined it needed to flow, but when done, it performed nearly identical to the OEM carb. Idled perfectly, had acceleration without hesitation and didn't use any more or less fuel than the original carb.

90% of all carbs can be rebuilt and restored to original performance and 80% of those do not need rebuild kits, but those that can't be saved are usually damaged during a previous service by a novice technician (something that cannot be replaced is broken) or the material is corroded from water so severely that it cannot be removed without destroying the carb itself.
 

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Discussion Starter #6
I know it's been a bit. The carb was bad. I replaced with another and it runs and idles great. It revs good while in neutral but when I try to ride it and accelerate the engine sputters. It died on me twice. Almost like its starving for gas. What are your thoughts. the person I bought from said it was sitting for 8 months. I had already replaced the fuel. I'm going to put inna new fuel filter. But also thinking of replacing the fuel pump.
 

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If it's starving for gas at full throttle, it may need a larger main jet in the carb - if it's sputtering in the mid range getting from idle to full throttle, the slide needle may need raised (if too lean) or lowered (if too rich) - if it revs good to near throttle then sputters and then dies when returned to idle and need a bit of throttle to restart, then the main jet is probably too big and needs a smaller jet installed - if it run better with the air filter out, then it either needs a new air filter or the carb needs re-calibrated to run leaner.

Sounds like you are making progress and getting there.
 

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Discussion Starter #8
I replaced the spark plug and put in a new fuel filter. I also raised the needle 1 slot. It purrs in idle and when I give it throttle is sounds good all the way through. I need to take it out and test it to see. The last time I thought it was good it stalled several times and had a hard time starting. I'll let you know. Thanks for the ideas to try. I do appreciate it.
 
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