Is Crank Bearing Failure Common?

BETHEVIPER said:
kinda

correct procedure is
fill tank up completely and add stabil. This keeps mosture from getting in tank. Empty tanks expand and contract like your lungs pulling atmosphere into them, leaving moisture. Full tanks have almost no air pockets to pull atmosphere into.
run the sled to get stabil into the carbs and fuel pump.
spray fogging oil, wd40, or what ever you want everyone has a favorite, into the carbs through the air box or pull the boots back. Do this till the sled starts smoking badly.
shut off the sled. Then pull the plugs, spray into the hole while turning motor with clutch. Do this to each then spin plugs back in hand tight.
ball up a rag and plug off your exhaust outlet. This is where alot of atmosphere goes into the motor when sitting.
a good coating of oil/silicone on the outside of the motor and exhaust helps with rust unless you haul your sled on an open trailer, then your screwed.

also, remove atleast your belt. leaving your belt on in storage will leave pitting on the secondary in that area where the clutch touches the belt. The best thing to do, is remove both clutches, clean and polish them daily through the off season.

in the fall, remove the gas from the tank and put it in your truck. Do not run it in the sled. clean carbs and new gas, your ready to go.

I have a more complete list to store a sled properly some where on here but this is the short list, minimum you need to do.
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All good info and as mentioned, don't use the treated/stored fuel for the first ride.

I do have to disagree with an empty tank breathing. If the tank is void of fuel there is no expansion/contraction taking place. The fuel is the cause of the expansion/contraction (fuel temp lower than ambient air is drawn in, fuel temp higher than ambient vapors are expelled out).

I sent an updated storage check list from Yamaha to JK Auto last year but never saw it posted. It was an addendum to the owner's guide that changed from recommending storing with a full tank to draining the tank.

... my clutches seem to be the only thing that gets polished these days.
 

SRXSRULE2 said:
Just wondering, was it idling high because it was sucking air? Possibly crank seals or an intake boot leak? Only asking because i noticed you said it was idling high. High idle = lean, lean = destruction.
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Not sure if they were leaking but it idled at 3,200 RPM all morning. We are going to sell it to Al's Snowmobile for parts.
 
BETHEVIPER said:
kinda

correct procedure is
fill tank up completely and add stabil. This keeps mosture from getting in tank. Empty tanks expand and contract like your lungs pulling atmosphere into them, leaving moisture. Full tanks have almost no air pockets to pull atmosphere into.
run the sled to get stabil into the carbs and fuel pump.
spray fogging oil, wd40, or what ever you want everyone has a favorite, into the carbs through the air box or pull the boots back. Do this till the sled starts smoking badly.
shut off the sled. Then pull the plugs, spray into the hole while turning motor with clutch. Do this to each then spin plugs back in hand tight.
ball up a rag and plug off your exhaust outlet. This is where alot of atmosphere goes into the motor when sitting.
a good coating of oil/silicone on the outside of the motor and exhaust helps with rust unless you haul your sled on an open trailer, then your screwed.

also, remove atleast your belt. leaving your belt on in storage will leave pitting on the secondary in that area where the clutch touches the belt. The best thing to do, is remove both clutches, clean and polish them daily through the off season.

in the fall, remove the gas from the tank and put it in your truck. Do not run it in the sled. clean carbs and new gas, your ready to go.

I have a more complete list to store a sled properly some where on here but this is the short list, minimum you need to do.
Click to expand...

no need to fill tank i dont believe. no reason that moisture will collect in it. wd40 wont do much. fogging oil for sure. better off running fuel system dry with todays fuel, using stabilizer or not. 6-8 months is a long time. i am going to go with my original plan. which is to empty tank, run a line from pump into sperate container and run the bitch every 4-6 weeks using fresh gas with a little stabil. each time. going to put choke 1/2 way on for 15 sec. or so before i shut it off.(as long as it does not foul any plugs.) sled will be in basement in a fairly stable envir. wont have any surprises come riding season.
 
number1kyster said:
Not sure if they were leaking but it idled at 3,200 RPM all morning. We are going to sell it to Al's Snowmobile for parts.
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You don't want to fix it, shouldn't cost that much to fix

I have an 02 viper with 8000 miles on it just replaced the main seals just to be safe didn't want any problems this winter,I don't think they have crank problems you just have to take care of it, any 2stroke if you don't do the off season maintenance then you will have problems its not just vipers
 
09nytro said:
You don't want to fix it, shouldn't cost that much to fix

I have an 02 viper with 8000 miles on it just replaced the main seals just to be safe didn't want any problems this winter,I don't think they have crank problems you just have to take care of it, any 2stroke if you don't do the off season maintenance then you will have problems its not just vipers
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correct
 
stein700sx said:
Do not the Viper and Srx have the same bottom end???
:hide:
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The Viper has a "pork chop" crank[2lbs lighter]...SRX has a conventional "full wheel" crank. The cases, oiling points, oil pump, and crank bearings are all the same between the 2000+ SRXs and all Vipers.
I am currently running a Viper crank in my 2002 SRX, three seasons with no issues so far.
 
number1kyster said:
Not sure if they were leaking but it idled at 3,200 RPM all morning. We are going to sell it to Al's Snowmobile for parts.
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My 86 indy went to als when it died, but it was past its time. That viper is not ready to be stripped and parted out yet.
 
Am i correct in saying that viper crank pins are not welded at the pins from the factory. If they are identical other than being lighter, it seems odd i know of 8 vipers lost center rod bearing. 3 of them in my garage right now. Anywhere from 3,500 to 9,500 miles on them. Just sayin.
 
ottawaair said:
Yep. Be very careful or they will BLOW right by you..

I don't see this happening. "Blow Up" right by me maybe.
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yeah stock vipers are not super fast but i find them to be powerful enuf. actually i really need to get a deeper lugged track, 2 much spinning most of time when u crank it, got decent picks. i think the oil cable setting is 2 lean from factory not enuf oil at smaller throttle openings.(mid range cruising) around 19.5 is my setting. i like it there. fine tuning jetting for conditions is important. an area where i need to put some time.
 
snomofo said:
I do have to disagree with an empty tank breathing. If the tank is void of fuel there is no expansion/contraction taking place. The fuel is the cause of the expansion/contraction (fuel temp lower than ambient air is drawn in, fuel temp higher than ambient vapors are expelled out).
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so your going to stand by the statement that a plastic 12 gallon tank, vented to atmosphere, empty, in a constantly changing temperature is not going to breath????? It is all about lessening the amount of air exchanging into the tank as well as the other side.

The other side is, gas that is dried onto the inside of your tank and inside of your pump and fuel lines leaves a mineral residue, this residue is washed off and mixed with the new gas as sediment, to either go through the carbs or to stick in the filter. If the tank, fuel lines, pump and carbs are filled, there is less of this mix with new gas. Carbs will evaporate a litte through the storage and need to be cleaned anyway.
 
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Clean and polish the clutches daily in the off season :D
That is dedication to the nth.
I'd be crazier then the nuthouse squirrel if I did that, lol.
 
ottawaair said:
Am i correct in saying that viper crank pins are not welded at the pins from the factory. If they are identical other than being lighter, it seems odd i know of 8 vipers lost center rod bearing. 3 of them in my garage right now. Anywhere from 3,500 to 9,500 miles on them. Just sayin.
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The cause of the problem is not the crank,(same bearings as srx) not the oilpump(same as srx), its the head and the ign. timing!!!

The center and mag cylinders have MORE compression then a srx does(compression adds heat) and the mono head cools less on the mag cyl., and to put it over the edge is the ign. timing, it has 8 degrees more then a srx(advanced timing adds heat to the piston).
The carbs have LEANER needles and nozzels in them sthen a srx does so its much,much easier to get detonation, thats what wrecks the rod bearings!! I have replaced many srx cranks as well to failed rod bearings. If you have sustained detonation, you will have a failed rod bearing in short order. It just gets beat to death from deto.

every viper you see blown up is the center and mag cylinders, not the pto... because the pto is less compression and even with the larger ign. timing it will survive from less compression(less heat), so the compression ratio of the center and mag is right over the limit for todays junk gas, and the timing just adds to the problem.
If you can reduce the compression in the other 2 cylinders you will eliminate the problems. You can do this by using aftermarket heads or reworking the stock head to balance out all 3 cylinders to the pto one(less compression). Or.... you have to richen up the fuel to protect against it, (raise the needles )and up the octane is the only way!
 
Part of the preflight for any recreational type aircraft is to drain a small amount of fuel from bottom of fuel tanks into a sight glass to check for water sediment ect.. this is because partially full fuel tanks breath and take in water laden air that cools. condenses, and deposits moisture in the tank, just like dew on the grass in the mornings. This is why aircraft fuel tanks are normally left full when the aircraft is going to be sitting for a while. A light aircraft will create GALLONS of water in their fuel tanks in a suprisingly short period of time!
LOL!....don't have to do this on B777s as they don't sit long enough and burn most of the fuel in their tanks when in use.
 
sideshowBob said:
A light aircraft will create GALLONS of water in their fuel tanks in a suprisingly short period of time!
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Hmm. I don't ever remember draining anywhere near a gallon, let alone a quart out of anything unless there was something abnormal going on or something that sat for years. Create gallons of water quickly? In what?....a Convair? LOL. :)

I store my sleds with Avgas. I run it through the system and store them this way but don't run it during the riding season. Personally... I don't like fuel pumps, lines and tanks sitting dry in the off season.... nor do I want today's junk ethanol gas sitting in them. Store them and get rid of the stored gas in the spring and then run fresh gas. I don't fill the tanks because I'm not overly worried about condensation in the that gas I'm going to get rid of in the spring and clean the carbs. It may not make a bit of difference but since Avgas doesn't go bad in a matter of months, I feel better with that type of gas sitting in the system.

Everyone has there own ideas as to which methods are best. Anything is better than letting a sled sit without fogging or without running it at all in the off season ...and then trying to run it in the spring with old gas that at best, may have been treated with some snake oil in a bottle. I know some really do not like the idea of starting them now and then during the summer ...but I feel that if you run them long enough and get it very warm on a track stand to get some oil moving through the parts....it's better than letting it sit. Obviously fogging is probably the best method. I'm fogging everything this summer but some years I just use the run every once and a while method.
 
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bottom line: for most situations- fog engine- make decision on fuel system. dont forget about the damn rodents.(if sled in vulnerable enviroment) at least remove air filter and stuff some rags in box. u should open hood fairly often to make sure they dont go to town on ya.
 
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