Hey guys I bought this machine knowing it had a burnt clyinder. It ended up being worse than I expected. One cyl. Destroyed and the other two scored, Mag. piston burned through and filled the case with crap.
So I opened it up and here is what I found. My question is the outter bearing seemed noisy and had a bunch of crap in it. The parts break downs i've seen don't show serviceable parts for the crank. I'm thinking this needs at least a bearing a maybe a rod....? The upper rod bearing shows signs of heat and the pin was a b%$ch to get out.
The two bearings on either side of the oil pump gear seem to have rolling resistance but the others roll easy. Not sure what to do, I plan to keep this machine and don't want to half *** this and be fixing it again.... Hoping someone what more experence will chime in.
Oh and I'm thinking the water pump seal is bad too....
M
So I opened it up and here is what I found. My question is the outter bearing seemed noisy and had a bunch of crap in it. The parts break downs i've seen don't show serviceable parts for the crank. I'm thinking this needs at least a bearing a maybe a rod....? The upper rod bearing shows signs of heat and the pin was a b%$ch to get out.
The two bearings on either side of the oil pump gear seem to have rolling resistance but the others roll easy. Not sure what to do, I plan to keep this machine and don't want to half *** this and be fixing it again.... Hoping someone what more experence will chime in.
Oh and I'm thinking the water pump seal is bad too....
M
Attachments
mopar1rules
Active member
vmax mike, where are you located? also, i think the oil seal behind water pump is what's out. was there any little puddles/drips of coolant in belly pan under that weep hole in the crankcase? if not, than for sure that oil seal and not water pump seal.
I'm down in Janesville.... Hard to tell the guy I bought it from unbolted the head with out draining the coolant so the engine compartment was a mess.
I cleaned the chassis and where was alot of oil under the engine but hard to tell what it was from. Does kind of look like a puddle of the same crud
I cleaned the chassis and where was alot of oil under the engine but hard to tell what it was from. Does kind of look like a puddle of the same crud
Attachments
I'm more concerned with the crank right now..... any thoughts?
mopar1rules
Active member
you said the outer bearings sounded noisy. well, they always have that "ticking" noise to them, as its just the rollers in the bearing. to get the crap outta those 2 large end bearings, you can simply take a pick and pop out the rollers. then take the cage out and simply clean in parts washer. rinse good w/brake cleaner and reinstall cage, then rollers and oil good. i would bet the farm its just fine. i don't know what to tell you w/the rods, as i'm not the one rolling the crank around, checking for "grumblyness" or vibrations in the rods.
They feel fine.... rod end was def. hot and shows a silver color due to the alum. maybe I'm being too cautious. Is there a spec. some where for the top of the rod that I can measure and compare to?
Also why are the bearings on either side of the oiler gear stiff do they have a seal in them? The rest spin like you expect from a ball bearing but those two feel stiff like they have a seal. It would stand to reason that they might to keep that gear lubed.
I might just take a ride to briston to see Pete Nydahl and have him peek at this crank to make me feel better.
M
Also why are the bearings on either side of the oiler gear stiff do they have a seal in them? The rest spin like you expect from a ball bearing but those two feel stiff like they have a seal. It would stand to reason that they might to keep that gear lubed.
I might just take a ride to briston to see Pete Nydahl and have him peek at this crank to make me feel better.
M
They will feel stiffer. The area in the case where that oiler gear is runs full of oil and I believe does have some kind of seal to keep oil from pouring thru.
vmaxmike said:
I always get a second opinion!!! even then things have been overlooked on my sled!!!
I know I expect my sled to run 8,000rpm ALL DAY LONG..... anything slightly off at that kind of twist is going to work its way to broke FAST!!!!
take your time, ask ?'s, and replace anything that makes you even the slightest bit nervous!!!! If you dont you'll never get what you want out of it!!!
just my $.02
Storms
Detonation, no question about it. Note the top of the piston looks like a sand blaster hit it. Viper noted for detonation at low range due to aggresive spark timing and bad head design.
The Mag piston? That damage was the piston & ring fragments in the cylinder, the guy rode it 15 miles home...
Wash marks seem ok on the other two, don't they?
Wash marks seem ok on the other two, don't they?
bolin22
New member
yes you can get parts for the viper cranks. you need to look on an older fische. the new fische doesnt show a breakdown. contact hauck if you need info, they rebuild them all the time.
mopar1rules
Active member
the center piston looks like it had good wash going, as well as the pto, but it also looks like things were possibly starting to lean out, as indicated by the scoring on the intake side. but then if the mixture was lean and the exhaust was getting hot, usually the exhaust side of the piston seems to get scored first. but, something definetly caused the exhaust side of the piston on the mag cylinder to get very hot, to the point that it melted a hole right thru the side, and caused the ring lands to distort, and then the rings could snag the exhaust port and break, which the debris then beat up that piston crown. my buddy has this same thing happen to him on his stock '00 srx this year, when he filled up w/91 octane. 15 miles later, his piston looked like yours. so, maybe it was water in the gas? low octane?
mopar1rules IT WAS NOT HEAT that destroyed that piston. Detonation makes them look sandblasted. Heat alone melts the piston. The mag side is the cylinder that does not recieve an equal amount of cooling and that creates a hot spot that causes detonation.
You convince a guy it is heat and he does not fix the real problem and burns it down again.......................
You convince a guy it is heat and he does not fix the real problem and burns it down again.......................
mopar1rules
Active member
stingray719 said:
you make no sense. you say it was not heat that destroyed that piston, yet you can clearly see that the side of the piston, underneath the ring lands on the exhaust side, is melted thru. look at how the ring land flows/bends down toward that hole in the piston. its bent cause that thing was molten hot from HEAT! the damage on the piston crown is from the parts of the rings and piston between the ring lands, ramming around in there, while the guy drove it for 15miles or whatever. detonation doesn't hammer in .060"-.080" deep pits. detonation on a 2-stroke piston will have more fine pits, that look like a sharp needle like pick, was poking around on the crown, around the perimeter of the piston.
mopar1rules
Active member
vmaxmike said:
what mods are done to this sled and whats the current jetting? what fuel was being ran when it blew? how did the carbs look? how do the intake boots etc look?
Stingray... this sled was on non-ethanol super. So what is the soultion?
mopar1rules said:
1900 miles bone stock no mods and non-ethanol super.
I havn't opened the carbs yet but will in the next day or so, I'm thinking it was in fact dirty carbs but open to other ideas.
agree with mopar it did run lean ...check carb or air leak ..............