550 pantera blowing engine - Snowmobile Forum: Your #1 Snowmobile Forum

kinb · 11-09-2007, 03:07 PM

I have an 05 pantera 550 liquid. I burnt a piston at 56 miles, dealer said the gas line was kinked off. i burnt the same piston at 650 miles, dealer said timing was off and replaced power pack. I burnt the same piston at 1250 miles and dealer said the crank seals were gone. I think they are grasping at straws and there is something more wrong with my engine. has anyone seen the same type of problem with this type of snowmobile? currently 1250 miles on engine and 1 more year warranty on machine.

**RJ Gleason** · 11-09-2007, 03:08 PM

That's a fan cooled right?

kinb · 11-09-2007, 03:10 PM

550 liquid cooled

**RJ Gleason** · 11-09-2007, 03:12 PM

Which piston?

kinb · 11-09-2007, 03:14 PM

sitting on the machine its the right hand

**RJ Gleason** · 11-09-2007, 03:17 PM

Mag side cylinder then.

Have you got any pics of the piston and cyl?
That would help with the diagnosis.

Without any visual aids, I'm going to say have the crank seals checked.

kinb · 11-09-2007, 03:21 PM

there is a hole in the center of the piston. the engine was repaired in march of last year and i did not ride it since, we lost our snow. the dealer replaced the crank seals the last time

red firecat 600 · 11-09-2007, 09:31 PM

that is not a seal leak that sounds like a timing or jetting issue causing a lean/hot condition, or the coolant system was not burped propley can you post pics of the piston

kinb · 11-09-2007, 09:40 PM

I o not have pics the dealer keeps the pistons but the piston gets melted away over time the plug turns a light gray with metal left on it. the piston will have a hole burnt through about 10mm in diameter and a concave crater about 20mm in diameter in the center of the piston. this engine has been done 3 times in 1200 miles

red firecat 600 · 11-09-2007, 09:58 PM

yeah thats not a air leak that sounds like a lean/hot condition but not a air leak lean i had that problem with my old sno pro it was a timing issue causing the problem

kinb · 11-10-2007, 07:35 AM

thats what the dealer said the 2nd time. so they replaced the power pack. this is why i am totally confused and cannot trust my cat

kinb · 11-10-2007, 07:42 AM

the first 2 time i would hear a pinging in the sled before she would go down the 3rd time it just shut off with no warning and the piston was not burnt completly through and once the engine cooled she started again. would it be a caomination of the 2 timing and crank seals and just maybe my sled is repaired. (hopeful)

**smallengineguy** · 11-10-2007, 08:15 AM

The pinging is preignition from being too hot or off timing. Are the stock plugs in it? May want to go down on the heat range.

tamacat · 11-10-2007, 08:28 AM

Good thing you still have a year warrenty left.

kinb · 11-10-2007, 08:28 AM

the stock plugs are still being used in the sled, what would you recommend

kinb · 11-10-2007, 08:30 AM

its good i have warranty but its not good when you are in the back woods being towed back out

**RJ Gleason** · 11-10-2007, 01:00 PM

Check the jetting and also the carb mounting flanges for any leaks or damage.

kinb · 11-10-2007, 01:34 PM

the flanges are ok and the dealer tells me the jetting is ok. do you kow of a cooler plug than the br9eya. iam aware the lower the number the hotter the plug but i am unsure what happens after 9 is there a 10. i am getting 21 to 22 miles per gallon maybe this is to lean and i should adjust the jets to a richer setting, any thoughts

kinb · 11-10-2007, 05:05 PM

i am thinking about changing to the br10eya. Do you think this plug will be too cold and get carbbed up and would i loose power. time will tell i guess

red firecat 600 · 11-10-2007, 07:26 PM

yes the br10eya is a good idea and 21 mpg is very good for a sled what kind of riding do you do trail back country ????