Well I blew up my new 02 Viper this past week end. It was about -30c, ripping along racing with an srx and an a/c f7. Put on 30 miles, cracked the throttle, hit 105 mph and blughh, she died. I started it up and it looked and sounded like it wanted to jump out of the sled and into the bush, so I quickly shut it down and hooked up the tow rope. I have started to remove the motor and found that #2 piston melted down scored the cylinder and the crank bearing is shot. The motor was to lean here are the reasons why: All stock and all stock settings, the gas station only had 87 octane with ethonol, it was -30c out, one screw for the clamp on the rubber boot to the carb was missing possably causing an air leak, and the oil cable was pulled out of it's holder. So any one of those or all of those caused the overheat. I will keep updating. I will be looking for parts as soon as I split the case and check the crank.
Wow! How many engines have went down this year? I guess we should not say Arctic Crap any more. Good luck with the repair. Al
blue missile
New member
i would'nt be quick to blame this one on yamaha, look at the details all of the above mentioned scenarios are human related and should not have happened.
daman
New member
did you read the lean part?? operator/owner error here..alswagg said:
Millinocket Rocket
New member
Haven't you guys in the midwest had ethanol for quite a few years now? We're just getting this past year or so in Maine.
blkmax600
New member
I hate to say it but I think this is a case of neglect.
YAMAHIZAL700
New member
With \all the sled burn downs this year my gut feeling is ethonol. It seems to be more popular in the last two years and lately we ve seen a bunch of burn downs. WHo knows. Vipers are know n to have the bearing issues so thats another part of the equasion.
Stock jetting with good maint, running 87 octane in Northern Ontario 2002 - 2006 was fine in those conditions on several Vipers for hundreds of miles. I too suspect poor maintenance.
Vipers are getting to the age where neglect is really taking a toll.
Vipers are getting to the age where neglect is really taking a toll.
Millinocket Rocket
New member
If the oil cable was out of its holder, wouldn't that be starving it of oil?
Millinocket Rocket said:
This is definitly not the fault of the machine. Yes we have had ethonol here for a while, but is is not in the premium 91 octane. Some of the small towns only have regualar 87 octane which has ethonol 10%.
I am not saying it was Yamaha's fault. I know poor maintanance was an issue but maybe the same apply's to fellows running Arctic. I have not seen any fuel stations in Indiana or in Northern Michigan which have Ethonal. This year has been a bad year on engines. We will probably see more of this in the future as the shelf life of fuel is getting worse. Good luck Al
daman
New member
if it was outa it's seat it would be pouring the oil in..Millinocket Rocket said:
Yes, which also leans the actual fuel mixture right? I feel that it is a toss up as to whether this will make it run hotter in the midrange.daman said:
However, at WOT the mixture should be the same with the cable pulled apart or not.
What are your thoughts on this, Daman or others?
daman
New member
i agree on that ding and the rest of your statment, i'd be nice to see some pics but i just feel it's lean failure all around and deto from shitty gas and. poor maint.Ding said:
TJ500
Member
Tg5593 said:
reasons are clearly written above... I'll number them more clearly..
1) -30 C
2) 105 mph
3) 87 octaane with 10% CH3CH2OH
4) carb boot probably leaking
5) oil cable out of holder does lean "fuel/air" mixture, but oil too is a combustible hydrocarbon so it's cause might not be as significant as all the rest.. one or all contributing together, who knows... it's all over but the rebuilding..
sorry to hear about this..
I'm going out to check on my carb boots immediately...
tj
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700
Member
Ethenol!
I have had nothing but trouble with 87 Ethenol in anything smaller than a car engine. After sitting too long it actually disolved the suction line in the fuel tank and completely gummed up the carbs. Yes I did let it sit too long but It will never go in any of my ATVs or sleds again. Avoid it like the plague!
As long as I'm at it, I think I'll blame the broken ring in my 440 on it as well 
700
I have had nothing but trouble with 87 Ethenol in anything smaller than a car engine. After sitting too long it actually disolved the suction line in the fuel tank and completely gummed up the carbs. Yes I did let it sit too long but It will never go in any of my ATVs or sleds again. Avoid it like the plague!
As long as I'm at it, I think I'll blame the broken ring in my 440 on it as well 700
I don't buy that the temp, speed, octane or oil cable contributed. However, the ethanol blend, carb boot, and possible dirty jets are likely culprits. Not trying to argue, this is just my opinion so it take it for what it's worth.TJ500 said:
Yes it really doesn't matter now, except it is always wise to identify the root cause in order to avoid a repeat. I would hate to see you put it back together and have it happen all over again.
Were you WOT or midrange throttle position when it occured?
valin
Active member
He mentioned he was racing, so you would assume WOT. At -30, he's going to be on the lean side, add that with 87 octane with ethenol, and yes, you're going to detonate. Even without ethenol in the fuel, there is a good chance of detonation with 87 octane fuel at -30. I find it very unlikely that the oil cable was an issue. I'm sure it wasn't running great in the midrange, and was probably loading up, but at WOT, the mixture wouldn't have been affected. The boots are faily ridgid, and if the other 3 bolts were securely in place, there was probably not an airleak. Of course, that is only an assumption. What would I do? Fix it, put in the 4th bolt on the intake boot, drain the fuel tank, throw in some good fuel, and drive it.
Ok here is some more info the oil cable was pulled out and taped, I think this is to compensate for the wrong cable adjustment. It should be about 20mm and it is only 4mm. don't think that had much to do with it. I was not racing at the time but I had been doing 85mph and cracked the throttle to 105 and it shut down. I have lots of pictures but not sure how to post them. The middle crank bearing is toast and everything else in the middle. I was told when I bought it(1 month ago) that the top end was just done. I will try to get the pics up and you can tell me what you think.
I thought when ethonal was added to fuel it bumped the octane to 89. This of coarse is if you start with at least 87 octane. If the fuel in this instance is 87 octane with 10% ethonal the base fuel must have been 85 or lower. Am I thinking correctly on this? If too much injection oil is added to fuel, the fuel burn will be lean, but the overall burn will have a lower temperature due to not being able to addiquatly burn the extremly oil rich mixture. The big question is now, 2nd seizer on engine, I would bet both are related. Why did the first siezure take place? Cloged main jet?? Was the carb boot bad at that time also?