BadAzzSRX
New member
Would you guys please look at these pictures and give me your thoughts on cause of burn down. This came out of my nephews 580 Formula Plus.
This is the Carb side, notice the piece of piston missing on top.
This is the Exhaust side.
Here's the top of it
This is the Carb side, notice the piece of piston missing on top.
This is the Exhaust side.
Here's the top of it
I have heard of people saying that the scratches on th intake side are from snow ingestion.
daman
New member
That erosion of the piston looks like from detonation,lean,running bad gas
or not enough octane.
top of that piston look way lean
..
or not enough octane.
top of that piston look way lean
..
tedgoesfast
New member
my friends 583 did this is was water half froze main jet went lean istall a water seperator in tank
daman
New member
And wuz up with ski-poo and only one ring!!!!! lol!!!!!
YAMMIEGOD3:16
Active member
LEAN SQUEAK !!! 3:16 (yammie tony)
BadAzzSRX
New member
Thanx.
After I pulled the cylinders off, I found 1" of new oil sitting in the base................this doesn't seem normal to me. Something must be wrong with the oiling system. The rubber boot for the carb had some white corrosion on it where it mounted to the head. I think it might have sucked air there.
I guess at this point, I'll replace what it needs and get it back together. Clean carbs. Drain/flush fuel. Replace fuel filter and oil filter (it actually has one inline from the tank). Verify oiling system is operating ok. Then start it and spray it for air leaks. Does that sound like a sensible game plan??????????
After I pulled the cylinders off, I found 1" of new oil sitting in the base................this doesn't seem normal to me. Something must be wrong with the oiling system. The rubber boot for the carb had some white corrosion on it where it mounted to the head. I think it might have sucked air there.
I guess at this point, I'll replace what it needs and get it back together. Clean carbs. Drain/flush fuel. Replace fuel filter and oil filter (it actually has one inline from the tank). Verify oiling system is operating ok. Then start it and spray it for air leaks. Does that sound like a sensible game plan??????????
daman
New member
Yes, it's a good start....
YAMAHIZAL700
New member
Sounds like a good game plan to me.
YAMAHIZAL700
New member
HOw you making out?
terret725
New member
thats def detination. if it was lean it would be the exhaust side. thats intake. u might ahve been borderline lean and some bad gas put u over the edge. what were u runing for gas? id start runing premium if i were u. i run it no mater what just so i dont have problems like that.
BadAzzSRX
New member
I'm waiting for a new piston right now. The one I pulled out had 75.89 on it. Everything I've looked up says it should be 76mm. The dealers micro fiche verified 76mm, but his cross reference book shows Ski-Doo updated the micro fiche part number to a new part number. The new part number says it should be 75.89mm. 
The dealer told me Ski-Doo had a lot of pistons seizing back in the day. He thinks a lot of the cylinders were bored incorrectly or slightly out of tolerence making some tigher than others. To fix the tight ones that seized, Ski-Doo had Dealers put in slightly smaller pistons to correct it rather than bore/hone the cylinders out to the correct spec. So now my 582 is probably a 581.??
He also told me to check the main jets in the carbs. On this sled apparently the bigger jet is on the Mag side of the motor. He said normally the PTO side is richer. I bought the sled used, so I wonder if the previous owner had the carbs swapped. I'll no more when I get home to check it out.
I will be drainging the tank and switching it over Premium fuel as a precaution.
The dealer told me Ski-Doo had a lot of pistons seizing back in the day. He thinks a lot of the cylinders were bored incorrectly or slightly out of tolerence making some tigher than others. To fix the tight ones that seized, Ski-Doo had Dealers put in slightly smaller pistons to correct it rather than bore/hone the cylinders out to the correct spec. So now my 582 is probably a 581.??He also told me to check the main jets in the carbs. On this sled apparently the bigger jet is on the Mag side of the motor. He said normally the PTO side is richer. I bought the sled used, so I wonder if the previous owner had the carbs swapped. I'll no more when I get home to check it out.
I will be drainging the tank and switching it over Premium fuel as a precaution.
To me that looks like a four corner seizure, (common on sleds that ingested moisture/snow/water-fuel) with continued use lead to the melt down...but I'm no expert...did this in fact happen while powder riding or following close to another sled that was lifting a lot of trail snow dust or did it go under water for a brief second or so or just after gassing up...
BadAzzSRX
New member
I helped him do a full service on it last year, but he never got a chance to ride it. This year he said "it'll be ok, I don't need to service it again since I never rode it". We were on a small pond behind my house, he made several passes WFO. It had a full tank of last years gas in it and he hadn't serviced anything. He got 9 miles out of it before it popped. Hardway to learn a lesson..........
daman
New member
Weatherbyman
Member
Classic detonation. The white specks, piston melted at the ring.
Probably old bad fuel as the previous post implies.
Probably old bad fuel as the previous post implies.
sport-nitro
New member
You should have left it at the pond ,saved your money and sent him to illinois to buy my vmax 600
BadAzzSRX
New member
sport-nitro said:
Man you said it........
As soon as we get it together he wants to sell it. Anyone want to buy some Tired Iron????