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Discussion Starter · #1 ·
Now that i have my sled running i need to tune my carbs. Its got about a good hours use on it but nothing over 20 mph. Heres how it runs. It starts up alright, need to prime it like 10 times. (i started it today, used 6 primes, started but had to prime it when it sounded like it was dying). It w idled well but a little high once it was started, around 2500-3000 according to my tach. So i let it warm up for 5-10 mins and rode around. I came to a stop to check the idle and it went down, around 2000. So i ran around some more and came to a stop, it wouldnt idle withought dying. when i first started it it smoked a little, then the more i ran it the more the smoke went away, when i was done riding there was hardly any smoke coming out. I havent checked the plugs yet. Where do i start with the carbs? I htink the air screw is out about 3 turns. I remember when it went to low idle (when it was about to die) i woud hit the gas and it would bog for a second then catch back up. what should i do with the carbs? Increase my idle screws, turn my air screws in?...
 

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Discussion Starter · #2 ·
oh yeah, also when i was going i hit the throttle pretty much all the way in and it took about a second or so for it to catch up and take off.
 

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I would start with your plugs, just replace them its cheap. Then check your intake filter to make sure everything looks good.
Dont prime too much, thats the reason for the puff of smoke, now your plugs are probably fouled. If you have to prime a bunch of times then your running lean, hence shooting fuel into your carb(priming). Fuel screw clockwise= leaner. Air screw clockwise richer, not same for both. If your sled is old then you probably should take carb appart and clean out the jets.
Make sure your sled is fully warmed up before you do any adjustments on your carb.
Let me know if this helps.
 

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Discussion Starter · #5 ·
some of it helps. I have new plugs but my dad said wait and tune the carbs before you put the new plugs in. If i didnt prime it it would have died though. Dont know what you mean by fuel screw, i have and air/fuel mixture screw if thats what youre talking about. Carb im not sure if it needs clean becasue ive cleaned it twice during the summer and its sat dry all summer but its not out of the question. Yeah, ill make sure the sled is warm when i adjust it.
 

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some of it helps. I have new plugs but my dad said wait and tune the carbs before you put the new plugs in. If i didnt prime it it would have died though. Dont know what you mean by fuel screw, i have and air/fuel mixture screw if thats what youre talking about. Carb im not sure if it needs clean becasue ive cleaned it twice during the summer and its sat dry all summer but its not out of the question. Yeah, ill make sure the sled is warm when i adjust it.[/b]


How did you clean the carb . ( take it apart or run cleaner through it)?

ED
 

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Discussion Starter · #7 ·
took it apart, sprayed carb cleaner every where. Made sure main jet and pilot jet were cleaned, put new inlet valves in, adjusted them, cleaned the float spindlesand the floats. new gaskets.
 

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Discussion Starter · #8 ·
i took my plugs out and thats all i did. Id say its running rich, but maybe they're good, idk.

right side is on the right, left side is on the left...




right


left





i cant remember, is it turn the air/gas screws in to richen the mixture? Or turn them in to lean the mixture?
 

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I'm no expert :lookaround: , and pictures can sometimes be deceiving but, left looks ok right looks lean. But I could be wrong. :confused: G.L.
 

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Nick,

Regap the plugs to .018". The look like their .040" which is too wide. You cannot do a plug test with old crusty plugs at 20 MPH. You need 2 new plugs (gapped .018"). Do a run on a long straight trail at 1/4 throttle and hit the kill button without releasing the throttle. Take the plugs out and see if they are chocolate brown to cardboard color. Do the same test at 1/2 throttle and re observe the plugs. Repeat at 3/4 and full throttle.

1/4 = low speed screws and pilot jet
1/2 = Jet needle (Position of clip) and Needle jet
3/4 = needle jet and main jet
full = main jet

The above circuits must have correct float level to perform correctly.
 

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Discussion Starter · #11 ·
ok, my manual says .016 so ill do that. I dont know when ill be able to get on a long straight away. itll have to be done when im on the trail.
 

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Discussion Starter · #12 ·
just curious, what would a wide gap cause the engine to do?
 

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Weak spark causing hard starting, miss fires and cylinder drop out at high RPMs.
 
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