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Carburetor differences??

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Hello, I have a 717 Broadmoor and a 4211H. They have practically the same motors but for some reason when I tried to interchange the carburetors it won't work. The 717's carb on the 4211's engine will run but even with the throttle closed it is running full throttle. Then when you try to throttle up, it just dies. I don't have a clue as to what is up with them. I haven't ran the 4211 since last year but the issue was the inlet fitting gt broken off inside the carb and I tried to drill it out but the drill went crooked and compleatly messed up the carb. So I just pounded an elbow into the carb and sealed it with Bondo but that didn't work. Any help asto why they did that is appreciated because I don't want to buy a new carb and then it not work with my tractor.

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quote:Originally posted by Simplicity7013H

but even with the throttle closed it is running full throttle.

id="quote">You mean when the throttle lever it at idle the engine is running fast? If so, the throttle linkage that goes from the governer to the throttle plate is too short. Question: does Martin have a carb for a 12hp flathead L-head Briggs? I would at least fnd the upper body for one since the rest of your carb is still good. They put those motors in a lot of machines so finding one shouldnt be too hard.Also, the cutting out problem might be because the 717 carb is too small?

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Originally posted by 1978Simplicity7016H
id="quote">My dad and I are going to check at Martins place. He should have one. I really like the 4211 and I found out that the problem was the main adjustment screw. I just swapped them out and it works good now. I'll let you know if I find anything over there.

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The adjustment of the gvernor on those engines can be at best tricky.

The high speed jet is real finiky, and just about the time you get it smooth, the darn thing likes to fall out of the float bowl.

i always had issues with mine surging. This was even after I spent $138 for a new carb, (The carb from 1988 was all rotted inside, and could not be repaired).sm00

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