Just got a used mtn Viper and had some old gas in it, pumped that out drained bowls, they looked great, and the thing will not start when left outside plugs bone dry , a few drips of gas in cylinders and fires and runs great, then takes a little longer than usual to warm up using choke in 1/2 position. Once the sled is warmed up it starts fine the rest of the day, 0-2000ft. 20-40 degrees could this adjustments, needles, idle air screws, etc. Got any ideas?
HELP Yami Viper won't start cold?????
- Thread starter jaws136
- Start date
sounds familiar...yer idle may be set to high...when it gets to around 30 degrees it wont start good at all...at least mine didn't...i will check around with some guys that still have mtn vipers and see what they say...may i suggest a 4 stroke it's way less maintence when left stock...if i figure something out i will let you know...
If it had old gas in it, I would pull the carbs and clean them. Take the pilot and main jets out and soak them in fuel injector cleaner. The varnish build up will reduce the hole size and cause it to run lean. Pilot jets have very small holes, so it dosn't take much varnish build up to cause a problem. HTH
I am a Yamaha dealer and and I agree with MTN_VIPER pull the carbs and throughly clean the jets I use Mercury Marine power tune to soak the jets in and spray it in all passages let soak and then spray with brake dry and blow all jets and passages out good and a lot of the times you won't see what was even in there because the jets and passages are so small
Thanks guys, the fuel looked good(clean no water, dirt, varnish) in the bowls so i stuck them back on. I guess they are coming off again. Hopefully this is it.
Don't forget to blow cleaner and comp air through the enrichener (choke) orifice. This controls your fuel supply for start up. Hold the choke lever on carbs full open and spray in the small orifice in the long shaft that extends into the bottom of the bowl. It should blow out in the carb throat.
