600 venture help - Snowmobile Forum: Your #1 Snowmobile Forum

rayri · 01-23-2005, 10:24 PM

just picked up this sled, took it out for a run today it back fires and there no power sled won't go over 45, but will rev up to 7-8
grand, the belt looks like new, and there was dry gas put in the fuel,, and there is also a virbration comming from the track

thanks ray

yamahabob · 01-24-2005, 11:25 PM

is this a twin or tripple?

Chances are your sled isn't sparking on all cylinders......take out 1 plug at a time with it still in the cap and place it on one of the bolts on the head, pull the chord with the key turned so it will spark and make sure all plugs are firing. If they arent change the spark plugs and if that still doesnt work, try replacing the coil.

My friends sled is actually doing the same thing.. but he is sparking on all cylders......i just put k&n air filters on the sled and ever since than it's been acting up......mainly cause i havent had it jetted properly.

Does the engine sound unhealthy when u are driving?

rayri · 01-25-2005, 02:30 PM

it is a 3 cyl, i will try the spark on the plugs,

thanks ray

rayri · 01-25-2005, 06:04 PM

getting spark on all 3 cyl,

yamahabob · 01-25-2005, 07:10 PM

my guess is that its something to do with the carburators. Either the jets are clogged or someone has added......like upgraded air filters or exhasut. the easiest thing to do is take it to a shop and let them see what they can find out......you could always try some carburator cleaner.....and just for the hell of it, open the chaincase and make sure everything looks good in there.

**smallengineguy** · 01-25-2005, 09:49 PM

How do the plugs look? Wet and black, or tan and dry?

rayri · 01-26-2005, 08:30 AM

plugs are wet and black