I got my 03 Viper ER out of the shed the other day to check it over and get it running before the snow comes. It started pretty easily on full choke, and would idle at half choke. As it warmed up a little it wouldn't want to stay running at half choke, but wouldn't run at no choke. It would idle alright if I held the lever between the half and no choke, but even after running for 7-8 minutes it stayed the same. If I opened the throttle it would run smoothly on no choke (I had the track raised so I could spin it) but as soon as I let off it would start stumbling and it backfired a few times.
The temp was in the upper 30's and there was actually pretty high humidity, but would that bother anything? I'm pretty sure the carb heaters were on if that makes any difference. I had the gas tank almost empty when I put it away in april and ran sta-bil thru the fuel system. Could the old gas have anything to do with it? I filled it up to half full with fresh gas before I ran it but maybe that hadn't circulated through yet. When I bought it last winter, it didn't idle very well but the dealership mechanic blamed that on the old gas in the system. I think he was right because after I ran a tank of gas thru it, it ran great the entire winter. The sled only has 1400 miles on it, so as far as rings and such it should be ok. Any ideas??
The temp was in the upper 30's and there was actually pretty high humidity, but would that bother anything? I'm pretty sure the carb heaters were on if that makes any difference. I had the gas tank almost empty when I put it away in april and ran sta-bil thru the fuel system. Could the old gas have anything to do with it? I filled it up to half full with fresh gas before I ran it but maybe that hadn't circulated through yet. When I bought it last winter, it didn't idle very well but the dealership mechanic blamed that on the old gas in the system. I think he was right because after I ran a tank of gas thru it, it ran great the entire winter. The sled only has 1400 miles on it, so as far as rings and such it should be ok. Any ideas??
Clean the carbs or have them cleaned.
Viper-Rules!
New member
Few things to check!
Have you checked your plugs? Your plugs could be slightly fouled up, which would result in a poor idle and cause back firing. Normally stabil will keep fuel fresh for a year as long as you add it within a few weeks of buying the gas. If the fuel was slightly stale when you bought it (ie the gas station doesn't sell alot of fuel) that could definatly be a possibilty. You should also check your power valves, they could be stuck half open or fully open which would cause a poor idle performance at low rpm. If this all checks out your carbs might need cleaning. You can try to increase the idle by adjusting the screw on top of the fuel rail near the middle cylinder. After the sled is warmed up the idle should be at about 1400-1600rpm. Good-Luck
Steve
Have you checked your plugs? Your plugs could be slightly fouled up, which would result in a poor idle and cause back firing. Normally stabil will keep fuel fresh for a year as long as you add it within a few weeks of buying the gas. If the fuel was slightly stale when you bought it (ie the gas station doesn't sell alot of fuel) that could definatly be a possibilty. You should also check your power valves, they could be stuck half open or fully open which would cause a poor idle performance at low rpm. If this all checks out your carbs might need cleaning. You can try to increase the idle by adjusting the screw on top of the fuel rail near the middle cylinder. After the sled is warmed up the idle should be at about 1400-1600rpm. Good-Luck
Steve
Like Ding said, the pilot jets are dirty, thats why it will run on the choke but not off the choke, the sled just pulls fuel from the choke circuit to run on the idle circuit which must go thru the pilot jets, youll find you cant see light thru them when you remove them, stabil or no stabil I have seen them plugged both ways, it all depends on the humidity and temp in which the sled is stored at, the hotter the shed in the summer the worse the gas gets.
jmendez29
New member
I'm not as experienced as these guys, but I had similar problem that ended up being the carbs. Last season, my SRX wouldn't idle to save its life. I either had to feather the throttle or flip the choke back and forth between half choke and no choke to keep it running. I hate working on carbs but a buddy talked me into cleaning them by myself and as soon as I did, it idled just fine. That would be my guess.
It was stored (covered) up on a "shelf" close to the roof in an uninsulated machine shed. It probably would get pretty hot up there with the sun on the roof. I'll take the carbs out tomorrow and see about cleaning them. I took apart and cleaned the carbs successfully on an Indy 500 once, but I don't have too much carb experience haha.
Also if I want to check the power valves, do I simply take the cover off where the cable enters on each valve? I'm not familiar with these at all, so if someone could explain it to me I'd appreciate it. Never worked on a 2 stroke before.
Also if I want to check the power valves, do I simply take the cover off where the cable enters on each valve? I'm not familiar with these at all, so if someone could explain it to me I'd appreciate it. Never worked on a 2 stroke before.
jmendez29 said:
That sounds exactly like my problem.
Ok nvm about the powervalves, I did a forum search and found all I need to know.
About 99% of the time, if it doesn't idle when you start it up after it's been sitting all summer, you will have to pull and clean the carbs and pay special attention to the pilot jets. When fuel evaperates from the float bowl it leaves behind a residue and the pilot jets being rather small, plug first.
Skidooslayer687
Member
I make it good practice just to take my carbs off before the start of every season and blow them out, just makes life a lot easier and cheaper in the long run from major engine damage. Lol plus if ya take them off lots you get real good at it, first time is a bit of a pain but after that its relatively simple. And as for cleaning the carb itself it isnt that bad either, im sure if you did a forum search on carb cleaning you would come up with an abundance of information on it.
Good luck
Good luck
marty f
New member
pilot jet
no brainer, pilot jet gummed up
no brainer, pilot jet gummed up
YAMMIEGOD3:16
Active member
WITHOUT A DOUBT PILOT JETS. 3:16 (yammie tony)
When I put the carbs back in will I have to bleed the cooling system because of the carb heaters? I have them out right now and I lost a little coolant when I took the hoses off.
Today I took the pilot and main jets (163.5 on all three I think) out and cleaned them, all three of the pilots were plugged. I cleaned out the bowls and then put it all back together and started it up, it seemed to idle fine at about 1800 rpm after it warmed up a little. I let it idle for a couple minutes then revved it up some, and after that it didn't idle the same, it wasnt running as smoothly and was more like 1400 rpm. It runs smoothly when I give it throttle. I also noticed that if I gave it hard gas it would bog slightly and usually make a "pop" sound. The temp was about 20 degrees. I haven't done anything with the powervalves yet if that makes any difference.
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try new plugs, just my 2 cents
I tried that, I didn't put new plugs in but I switched to some good spares and it made no difference.
Your motor probably doesnt like the old gas that gummed up your carbs
Probably need to go through and clean carbs again. Take the pilots out and clean them again. You should be able to see day light looking right through it from top to bottom. CLEAN CLEAN CLEAN the side ports!!!! You brought all that bad gas back into your fuel system
Probably need to go through and clean carbs again. Take the pilots out and clean them again. You should be able to see day light looking right through it from top to bottom. CLEAN CLEAN CLEAN the side ports!!!! You brought all that bad gas back into your fuel system
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