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Posted

I don't have any lack of power on short hills, but when I get a long uphill road the ATV will slow way down to about 30KPH. If I work the throttle to give it more gas it just gets worse. Then if I let up on the throttle it runs better, but of course slows down even more. Am I looking at a carb problem, or what? I tried getting at the air screw, but can barely get a screwdriver in it and then can't adjust...won't turn at all. I cannot find a fuel adjustment screw anywhere I can see on the carb, and the manual does not show one. My plug is burning black, wouldn't that be too much fuel, and how do I correct that? It may be that the engine is flooding when I go uphill and throttle up.

Posted

Are we talking steep enough hills that it would change the float level enough to run to lean?? Short hills the fuel level wouldn't be changed enough to be effecTed? ?? Just a thought

Posted
Are we talking steep enough hills that it would change the float level enough to run to lean?? Short hills the fuel level wouldn't be changed enough to be effecTed? ?? Just a thought

I'm talking about a long hill maybe a half mile and about 40 degree angle. The first 70 yards or so don't seem to bother it, then it starts acting like it's starved for gas, but pumping the throttle just makes it worse. If I idle down to about 3kph it will keep going, barely. As soon as the hill goes to about 20 or 25 degree slope, it starts improving. Short hills, no matter how steep don't phase it.

My fuel pump is working when I take the fuel line off and test it. (I do have a new one I might try). The plug is burning rich, but no buildup. I'm also working with a full gas tank, the air lines to carb, and fuel tank are clear as is the breather line from the carb that hangs over the air filter housing. I'm operating in the same climate and altitude as I have been for the last 4 years.

Posted
I'm talking about a long hill maybe a half mile and about 40 degree angle. The first 70 yards or so don't seem to bother it, then it starts acting like it's starved for gas, but pumping the throttle just makes it worse. If I idle down to about 3kph it will keep going, barely. As soon as the hill goes to about 20 or 25 degree slope, it starts improving. Short hills, no matter how steep don't phase it.

My fuel pump is working when I take the fuel line off and test it. (I do have a new one I might try). The plug is burning rich, but no buildup. I'm also working with a full gas tank, the air lines to carb, and fuel tank are clear as is the breather line from the carb that hangs over the air filter housing. I'm operating in the same climate and altitude as I have been for the last 4 years.

Plugged pipe?

I always start with a good carb cleaning to eliminate that aspect.

Posted

Ultimately, it would seem, I need to clean the carb. First, I have added carb cleaner to the gas. I'll give that a chance. Getting the carb out is going to be a project. So much plastic, so much iron, so many rusted bolts to get at before getting any access to that carb. Surely there is a better way to build these machines for access to the mechanicals.

Posted

Really seems to me like your float is out of adjustment in your carb...the needle valve that controls fuel level in bowl...going up hill pushes fuel to back of carb make float sit higher stopping fuel from coming in sooner I'd make sure your float level is at spec

Posted

Okay, after all, it's almost always the simplest answer. When this problem began, I remembered that the breather hose from the carburetor was difficult to get at. I regularly get mud wasps in the hose and have to clean it out, so I decided to get a new longer hose. Well, apparently that restricted enough air so that it would starve for air on the long tough hills. I cut the hose down to about 10 inches and "voila" the problem was solved. Now, I have plenty of power for those long uphill roads (we can travel on the highway here in Panama) through the mountains. No more bogging down.

Thanks for all your suggestions, they were still on the money for possible solutions for this type of problem and they did lead me to the carburetor for the end result.

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