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Hello, I just picked up a couple 89 ski's one is a Mach1 the other is the mx lt. Both run however the mach 1 is giving me some carb trouble. The guy I bought it from said it would not idle while riding it.
Basically whats going on is that once it is primed it starts right up, runs until the gas from the prime burns then dies. If you have the gas lever pressed a bit it will run fine. I have fully disassembled the carbs and cleaned them pretty well.Checked all fuel lines and fuel filtersfor garbage, checked the fuel pump, checked the gas shutoff lever. I did have it idling at one point, but it was reallly rich and bogged under gas until around 30 rpms then it would begin to rev fine. When I first examined the carbs the screw located on the opposite side of the idle screws where fully seated, so I turned them out like 1 and a half turns. the pilot jet I believe, the one inside the float bowl next to the main jet, was also fully seated, so I turned out 2 and 1/4 turns. Probably not the correct setting, just using some streetbike carb settings lol, anyway its still not working.

I have come to the conclusion that it is the mixture screw setting or something along those lines. Can anyone help me out with the correct turns out or how the stock setup of the jets should be? I also was browsing another post and saw that the carbs are not the same...or one carb is for a specific side, if so could anyone give me the correct numbers for that also? Any help would be appreciated, I have ordered a manual but ti hasn't arrived yet.
 

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The 1989 Mach 1 needs to have the pilot jets tightened back up (brass jet ahead of the main jet). Sounds like the float levels need to be set too. Float level is checked at the end of the float tab to the float bowl gasket flange 16-18mm.

The correct carbs are : VM38-171 (PTO side) and VM38-172 (MAG side). Main jets are: 260 (PTO side) and 290 (MAG side). Pilot jets are 45. The Jet needles are: 6DH8/2 (2 being the needle clip in the second groove from the top). Needle jets are:p-2 (480). Throttle valves are 2.5 cut away.

The air screws should be 1 1/2 turns out from lightly seated. Idle speed screw should be on the same side as the air screw and should be set to acheive 1800-2000 RPM at rest warm.
 
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