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Discussion Starter #1
Okay guys, my sled is a '02 Z370 with a single VM style carb
(VM-32 I think)
According to the owner's manual there are 4 simple adjustments a person can make to the carb
1. Adjusting Choke Cable
2. Adjusting Piston Valve
3. Adjusting Pilot Air Screw
4. Adjusting Engine Idle Speed
I'm pretty sure my sled is running rich, as it feels like it "flooding itself". eg. cruising at half-throttle, go to full throttle and it will either cut-out (though still running) or take off, and then cut-out.

My choke cable is fine, and the engine idle's fine, so I can rule out those two adjustments.
So I need to know, to lean out my fuel/air mixture, is it the Piston valve I need to adjust? or the Pilot Air Screw? Do i turn it in or out? how much do I turn it in/out?

The engine did the same thing last year, and we took it to the dealer to fix, he fixed it and it ran fine all year....same thing happenned this year, but this time, I want to fix it.

Thanks guys :)
 

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TRY ADJUSTING YOUR PILOT AIR SCREW TURN IN ABUOT A QUARTER TURN AND SEE WHAT HAPPENS.

GOOD LUCK!
 

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I agree. The air/fuel mixture seems not rich enough. Move the pilot air screw to let more air in.
 

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Discussion Starter #5
k, that didn't work, the pilot air screw doesn't seem to be the problem as the sled ran best with the screw where it was before I started messing with it.

The problem again: If I give it too much gas, it kills itself, though doesn't stall, if I go constantly onto the gas slowly, once I get to full throttle the throttle will cut out and won't come back until I let off the throttle. Sounds like it's running rich right? so how I do I fix this? note: the old gas from last year, and the fuel stabilizer is still in the tank, but I don't think it should be affecting performance this adversely... :confused:

HELP PLEASE!!! :eek:
 

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Discussion Starter #6
maybe it's not a carb problem....I just fooled around with it for a while....didn't help

Is is the gas? could the lower octane from sitting affect the sled so much?
 

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burn up that tank of gas and see if it runs better i guess, i have heard that the gas stabilizer stuff will cause sleds to do some funy things at times
 

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STABILAZER SUCKS,AND IMO SO DOES FOGGING I WILL JUST FIRE IT UP EVERY COULPE OF WEEKS IN THE SUMMER AND BRING UP TO TEMP AND I HAVE NEVER HAD A PROBLEM AT THE BEGINNING OF THE SEASON. RODE MY LAST SLED FOR FOUR YEARS AND NEVER TOUCHED ENGINE OTHER THAN ONE NEW SET OF PLUGS EVERY FALL RAN FINE AND NEVER STRANDED BUT THAT'S ONLY MY
OPINION
 

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BTW G-FORCE, TRY SOME DRYGAS SOUNDS LIKE YOU MAY HAVE WATER IN THE GAS.
 

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Discussion Starter #11
Thanks for the replies all
01MXZ800 said:
BTW G-FORCE, TRY SOME DRYGAS SOUNDS LIKE YOU MAY HAVE WATER IN THE GAS.
what's Drygas???

Haven't cleaned the carb, but the sled only has 500 miles on it, and I strain all my gas.

I'll throw in a new set of plugs too :cool:

Thanks :)
 

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DRYGAS IS AN ADDITIVE FOR GAS THE REMOVES WATER-GAS LINE
ANTIFREEZE THE SAME THING. I USE A HALF A PINT EVERY THIRD TANKFUL TO KEEP WATER OUT HOPE THIS HELPS

GOOD LUCK!
 

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Did you pull the spark plugs yet? Check the color on them. Should be burning a "Amber orangish." The way it sounds your plugs will be very dark if almost black. A rich micture.
I'd definately drop the float bowl and get a fresh tank of gas. No mater how much stabil you put in, there is always a chance for the carb to gum up/tarnish clogging the jets. Gas these days with all the additives goes bad much quicker, I've heard some people say 3 months tops before you get some serious tarnishing going on.

01mxz, do you store your sled in a shed/garage? Just curious as I know with my bikes I will only fire them up if I can run them at operating temps for ten minutes or so to keep condisation at a bare minimum. During storage I will not start them at all until I plan to put miles on em. Just curious if you've had any problems.
 

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Discussion Starter #14
Thanks again guys :cool:
chase9119 said:
Did you pull the spark plugs yet? Check the color on them. Should be burning a "Amber orangish." The way it sounds your plugs will be very dark if almost black. A rich micture.
I'd definately drop the float bowl and get a fresh tank of gas. No mater how much stabil you put in, there is always a chance for the carb to gum up/tarnish clogging the jets. Gas these days with all the additives goes bad much quicker, I've heard some people say 3 months tops before you get some serious tarnishing going on.
I did pull the plugs, one of them is a nice brown color, the other is black. I only have 1 carb though keep in mind :confused:

I'm going out to work on it tomorrow, maybe tonight, so I'll definetly get some fresh gas in there, and a new set of plugs, see what I can do about cleaning the carb too. I'll see what the Dad(pays the bills) thinks about adding some DryGas (is that just ethanol?)
 

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Ummmmmm......What is your spark plug heat? Do you have a BR8ES or a BR9ES? I opened up my sled and found that I had a 8 in one cylinder and an 9 in the other. Changed them both to 8 and runs super duper now!! :D

Edit: Drygas or Deicer (I think) is only like $4 a bottle and all you have to do is dump it in your gas. I dont think it is an ethonal.
 

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gas line deicer is like under a dollar a bottle at my local wal-mart, for that price it cant hurt to dump it in
 

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Discussion Starter #17
Just thought I'd fill everyone in:
1. Screwed around with the carb - didn't help
2. Drained old gas, put new gas in - didn't help
3. New plugs - Didn't help
4. Look in airbox/check air filters - didn't help
5. Found out one of the plugs was screwed - helped
6. Put one of the old plugs back in - helped (only with power though)
7. Screwed around with carb - didn't help
8. Went for a long ride - didn't help
8. e-mailed AC dealer - helped
10. call back from AC dealer - helped
Dealer says I have to clean the jets in the carb, he's 99% sure that's what the problem is. guess what I'm doing tomorrow morning? :cool:....this better work.....
 

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Discussion Starter #18
Cleaning the carb didn't help :(

So, my dealer, also a family friend, drove over to my cottage (an hour drive) and fixed the problem personally. It was the Emergency-engine shut-off switch....when you pressed the throttle certain ways it would cut the ignition to the engine....

disconnected it and everything runs good....soooo annoying....

Thanks for the advice everyone :cool:
 
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