990 problem

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454chad

454chad

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cheboygan mi
hi everybody i am having some issues with my carb i just put a wt 990 on my mt first thing is i have my high set at 1 1/2 and low is 1 1/4 and at that setting i have to crank my idle all the way up but it runs great and starts good but it don't run rite on high speed it seems to be starving for fuel and runs missy after 1/4 throttle seems like it is running on the low speed jet and thats it i did install a super bee but that seems to be working rite thank you for any info
 
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you running the standard 30cc hy motor? If you are, set the low speed fuel needle @ 1 turn out. Turn the high speed fuel needle in 1/4 turn. You cannot destroy -seize the engine with the lo-speed adjustment. You can seize with the hi-speed needle adjusted too lean. Start the engine, let it warm up for 5 minutes or so. turn the lo-speed needle and listen to the rpm. clock wise leans the engine- counter clock wise richens the engine. find the point of highest rpm, then turn counter clock wise just a slight bit. OH, when I say turn the hi speed 1/4 turn- turn it in 1/4 turn from your 1 1/2 setting. This will still be a lot of fuel- rich. The only thing that screws up your kill switch is running a non-resistor plug, it could cause a no spark condition.
 
alfred e numan said:
you running the standard 30cc hy motor? If you are, set the low speed fuel needle @ 1 turn out. Turn the high speed fuel needle in 1/4 turn. You cannot destroy -seize the engine with the lo-speed adjustment. You can seize with the hi-speed needle adjusted too lean. Start the engine, let it warm up for 5 minutes or so. turn the lo-speed needle and listen to the rpm. clock wise leans the engine- counter clock wise richens the engine. find the point of highest rpm, then turn counter clock wise just a slight bit. OH, when I say turn the hi speed 1/4 turn- turn it in 1/4 turn from your 1 1/2 setting. This will still be a lot of fuel- rich. The only thing that screws up your kill switch is running a non-resistor plug, it could cause a no spark condition.
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i am running a 29cc stuffed crank i have tried the low a 1 turn and it runs worst then but still starts and idles perfect i tried the h at 1 1/4 and i doesn't help still runs like it is starving it is almost like it's to rich because it only revs to a certain point then flat lines
 
look very closely at the intake manifold gasket area, the gasket that usually leaks is the one that is next to the engine, the engine shroud hides it. look closely at the gaskets on the bottom end- case- cylinder gaskets. 2 bolt engines can be a chore to get leak free, but it can be done. no idea if this is the problem- its just a suggestion.
 
alfred e numan said:
look very closely at the intake manifold gasket area, the gasket that usually leaks is the one that is next to the engine, the engine shroud hides it. look closely at the gaskets on the bottom end- case- cylinder gaskets. 2 bolt engines can be a chore to get leak free, but it can be done. no idea if this is the problem- its just a suggestion.
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i checked all that it is dry no oil any where it might be a bad carb though thanks for your time
 
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