Ive got an 04 mtn viper, ive put 5500 miles on it...shes never had any problems, except for a tree or 2 jumping out in front of me. End of last season, started beginning of april, the dcs light starting popping. It only happened 2 or 3 times that first day. I contributed the light to the riding conditions that day, warm spring afternoon, high elevation 11,000+ and back down to 7500. Next time I rode, normal riding conditions for my area, happened again after 30-40 minutes of riding trail, so I took it back to the trailer. Thought it might be bad gas (rash of bad gas around the area, few sleds damaged), drained most of gas, replaced with new. Took the sled out one last time, was beginning of may, did it again after an hour of riding. Light only goes off about 7000 rpm, around 40mph. So I put fuel stabalizer in the tank, ran it for 10-15 mins to get it mixed and in the system, and parked it in the garage for the summer...
Flash forward to last week, tried to move the sled, it wouldnt start. Dead. Changed plugs, nothing. Doesnt even think about turning over. Pulled the plugs again to look at them, and I happened to notice the left side motor mount bolts were gone. I know they were there before the beginning of last winter. Maybe that was causing the dcs light to pop? excess vibration, knock sensor thinks its detonation?
Im sure I need my carbs cleaned, its been a couple years, hopefully thats why it wont start...its the dcs light that worries me. From what I can see in the cylinder, doesnt look like any detonation pits or scars. sorry about the long story, but anyone have any ideas about this? Im hoping its as easy as the motor mount bolts...
thanks
Flash forward to last week, tried to move the sled, it wouldnt start. Dead. Changed plugs, nothing. Doesnt even think about turning over. Pulled the plugs again to look at them, and I happened to notice the left side motor mount bolts were gone. I know they were there before the beginning of last winter. Maybe that was causing the dcs light to pop? excess vibration, knock sensor thinks its detonation?
Im sure I need my carbs cleaned, its been a couple years, hopefully thats why it wont start...its the dcs light that worries me. From what I can see in the cylinder, doesnt look like any detonation pits or scars. sorry about the long story, but anyone have any ideas about this? Im hoping its as easy as the motor mount bolts...
thanks
If its been a couple years on the carbs,,, bet U got some crud in there to cause a lean condition.... Replace mounts and definitely clean the carbs and give it a try.... good luck...
ViperXC
New member
Cleaning those carbs every fall will do wonders. I have lost a couple motor mount bolts along the way as well.
do you think the missing motor mount bolts would/could cause the dcs light to go off? little bit excess vibration that the knock sensor might think is detonation?
instal said:do you think the missing motor mount bolts would/could cause the dcs light to go off? little bit excess vibration that the knock sensor might think is detonation?
Excess vibration could definatly cause a sensor to malfunction. The reason it wont start is the jets are probably plugged. Clean the carbs and she should fire up. Get some bolts put back in 1st though. Good luck


carbs have to be plugged...tonight I syphined all the old gas out, put in 2 gallons of good clean gas 91 octane, 3 brand new BR9ES plugs and pulled about 25 times, nothing. I pulled the plugs after and they were for the most part bone dry. Looked inside the cylinder, looked the same as before I started pulling. Am I wrong to think that the plugs should at least be somewhat wet after 25-30 pulls?
3 words...clean the carbs!!!
For some reason Im sorta nervous about doing that myself, first time and all. I bought her new in 04 and have never cleaned the carbs myself...local shop wants to charge me 5 hours labor minimum, @ $97/hr, so im looking at $500 (thanks to the triple cylinders). I know I can do it, with all the faq's on here and all the repair manuals I have. Just wish I had someone looking over my shoulder that knows what their doing...
simple advise: you have 3 carbs on a rack there. take them apart 1 at a time, leaving the other 2 intact. remove all the bowls, careful here, the stock phillips screws are easy to strip out. now, pay attention as your removing components from only one carb. ie, pilot, main, air screw(run this in first counting the turns so you can reset later). now clean that carb and its components and you have 2 untouched carbs for reassembly reference, consider them the "someone looking over your shoulder". by the time you get to the third carb, you probably wont need to look at the other two. jump on in there, get your feet wet, you can do it! pay attention to detail and you will be fine. good luck!
5 hour???
They are ripping you off bigtime. They will do that in 1 hour or 1,5 hour if they are really slow and lazy. I am no mechanic but I could disassemble those (as much as you need to clean them) in half an hour, follow mrviper700's "how to clean carbs" post and then put them back together.
They are ripping you off bigtime. They will do that in 1 hour or 1,5 hour if they are really slow and lazy. I am no mechanic but I could disassemble those (as much as you need to clean them) in half an hour, follow mrviper700's "how to clean carbs" post and then put them back together.
instal said:For some reason Im sorta nervous about doing that myself, first time and all. I bought her new in 04 and have never cleaned the carbs myself...local shop wants to charge me 5 hours labor minimum, @ $97/hr, so im looking at $500 (thanks to the triple cylinders). I know I can do it, with all the faq's on here and all the repair manuals I have. Just wish I had someone looking over my shoulder that knows what their doing...

staggs65
Moderator
like snowdad4 said, to fix this go to the hardware store and replace with stainless button head allens, well worth it, your going to be doing this every yearscrews are easy to strip out
ok, so i got the carbs out of the engine tonight...that was actually pretty easy. Tomorrow I get to clean them.
Questions:
The slide height is a different height on the center carb, not by much, maybe 2mm...should this be?
On the cylinder closest to exhaust, the air jet is turned maybe a quarter different than the other 2 cylinders...should this be?
Tomorrow when I open it up, what main jet and pilot jet should I find in there? Im riding 8,000ft-10,000+, usual temps -5 to 35 degrees f...a 141.3, 143.8 or 145 or what? When I bought it new, the shop said it was set up already, but Im still wondering. How do I know specific jet #'s? Is it stamped onto the jet itself?
Questions:
The slide height is a different height on the center carb, not by much, maybe 2mm...should this be?
On the cylinder closest to exhaust, the air jet is turned maybe a quarter different than the other 2 cylinders...should this be?
Tomorrow when I open it up, what main jet and pilot jet should I find in there? Im riding 8,000ft-10,000+, usual temps -5 to 35 degrees f...a 141.3, 143.8 or 145 or what? When I bought it new, the shop said it was set up already, but Im still wondering. How do I know specific jet #'s? Is it stamped onto the jet itself?
and whats the normal fuel screw setting? when I get to that, im going to tighten down first and see how many turns in it goes, so I'll have an idea where to set it back to, but any idea what the normal setting is?
Definitely find another dealer-shop to get quotes or general information of a sleds spec's.. Welcom to TY.. you'll find help here...
slide heights should be the same. they are adjustable. dont know if its covered in the tech pages, if you cant find it, let me know, i will give you the info. dont have any jetting info in front of me for the 04, again maybe listed in the tech section. the jets are stamped. the pilots are on the side, the mains on top. tiny as little numbers that for me require a magnifying lens or one of my kids.instal said:ok, so i got the carbs out of the engine tonight...that was actually pretty easy. Tomorrow I get to clean them.
Questions:
The slide height is a different height on the center carb, not by much, maybe 2mm...should this be?
On the cylinder closest to exhaust, the air jet is turned maybe a quarter different than the other 2 cylinders...should this be?
Tomorrow when I open it up, what main jet and pilot jet should I find in there? Im riding 8,000ft-10,000+, usual temps -5 to 35 degrees f...a 141.3, 143.8 or 145 or what? When I bought it new, the shop said it was set up already, but Im still wondering. How do I know specific jet #'s? Is it stamped onto the jet itself?
so i have a 140 main jet in there...on the spreadsheet for jet settings, that jet is for temps to 40 degrees f. i only ride in temps that high for maybe a month...should i have that as a main jet?
For 8300-10000 at -20F to 0F it shows 145 mains, 55 pilots, needle at 2.5, and fuel screw at 3-1/8...im sure others will chime in on what you should run...i think by running that 57.5 pilot you dont have to turn the fuel screw out as far, I could be wrong though. If that was me Id change out to like a 143.8 main and maybe even a 145.
If you run that 140 main in colder temps you may run too lean. NOT a carb expert by any means. Unsure if that 57.5 pilot will make up for it or not.
On a side note after reading youve been running that for 5500 miles why change it? If it's worked for that long?
If you run that 140 main in colder temps you may run too lean. NOT a carb expert by any means. Unsure if that 57.5 pilot will make up for it or not.
On a side note after reading youve been running that for 5500 miles why change it? If it's worked for that long?
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then to top it off, carb closest to exhaust has a 142.5 main jet...while the other 2 mains are 140's...is that right? So my carbs are as follows:
carb closest to exhaust- 142.5 main, 57.5 pilot, fuel screw 3.3/8 out
middle carb- 140 main, 57.5 pilot, fuel screw 3.3/8 out
clutch side carb- 140 main, 57.5 pilot, fuel screw 3.1/8 out
and exactly, should I change it, its been running fine for 5000+ miles...I do go through alot of spark plugs though...
carb closest to exhaust- 142.5 main, 57.5 pilot, fuel screw 3.3/8 out
middle carb- 140 main, 57.5 pilot, fuel screw 3.3/8 out
clutch side carb- 140 main, 57.5 pilot, fuel screw 3.1/8 out
and exactly, should I change it, its been running fine for 5000+ miles...I do go through alot of spark plugs though...
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