Detonation in Skidoo 850

[rknight111]

My older 17 850 ended up with detonation in the mag side of the engine taking out the jug, piston and head. The engine had approximately 1400 km. First thing im thinking is Bad Fuel? Any other thoughts. Can we send the fuel in to see what the octane is and where and what are the procedures for that. As an Environmental consultant we have special procedures for handling fuel but we are not doing BTEX we are looking for octane.

 

[maxwell]

as i said on the phone i havent seen an 850 go down from detonation yet...generally thats a polaris deal. Post photos of the cylinder,piston and head

 

[rknight111]

as i said on the phone i havent seen an 850 go down from detonation yet...generally thats a polaris deal. Post photos of the cylinder,piston and head

Ill ask Tom at Motts to send me some photos

 

[Caper11]

If it truly had detonation, there would of been a warning flash on the screen and the ECM would flag it.

 

[Mountainman52]

My older 17 850 ended up with detonation in the mag side of the engine taking out the jug, piston and head. The engine had approximately 1400 km. First thing im thinking is Bad Fuel? Any other thoughts. Can we send the fuel in to see what the octane is and where and what are the procedures for that. As an Environmental consultant we have special procedures for handling fuel but we are not doing BTEX we are looking for octane.

The 2017 SKIDOO SUMMIT 850 was ........EXPERIMENTAL SLED from SKIDOO...........LOTS & LOTS OF PROBLEMS MOST PEEPS CALL THEM POS............

 

[ctd]

Tom is very wise, we've had some interesting discussion on cause of death. Always ending well & in agreement, I would be interested in seeing some photo's.

The KR detection & retard is very good with E TEC's, it has saved many from catastrophic failure. I've seen failures when you have a very slight lean condition the causes over heated piston crown.........won't trigger knock. Those you can see the motor suffered over a long period of time.

If you are getting fuel from hi volume gas pumps unlikely to have bad gas. Metal tanks are bad news, trouble with steel & built in trailer Aluminum. Restricted flow from plugged in tank fuel filters, has been a issue.

One more bad fuel comment, NA motors in elevation will run happily on low octane fuel. The cylinder pressure is so low premium fuel is hurting power.

 

[tmo1620]

Tom is very wise, we've had some interesting discussion on cause of death. Always ending well & in agreement, I would be interested in seeing some photo's.

The KR detection & retard is very good with E TEC's, it has saved many from catastrophic failure. I've seen failures when you have a very slight lean condition the causes over heated piston crown.........won't trigger knock. Those you can see the motor suffered over a long period of time.

If you are getting fuel from hi volume gas pumps unlikely to have bad gas. Metal tanks are bad news, trouble with steel & built in trailer Aluminum. Restricted flow from plugged in tank fuel filters, has been a issue.

One more bad fuel comment, NA motors in elevation will run happily on low octane fuel. The cylinder pressure is so low premium fuel is hurting power.

Yes that’s very true, the only time I’ve ever had fuel issues (octane codes) was riding around home, I have to run straight av gas to run around here and run 50/50 in the mountains

 

[rknight111]

We were riding in Swan Hills at there rally. Road 45 km of the 130 km trial.

 

[tmo1620]

We were riding in Swan Hills at there rally. Road 45 km of the 130 km trial.

So you were definitely in the lower elevations of the swan hills then, still roughly 3200’ though

 

[oler1234]

I have a octane tester, it is fairly accurate. Not lab grade though, just need a sample

You can burn a engine down from lack of octane

 

[mclean]

I have a bunch of race fuel that is a 7 years old. I'd love to have it tested haha.

 

[ABMax24]

I have a bunch of race fuel that is a 7 years old. I'd love to have it tested haha.

If it's sealed I bet it's still good.

 

[mclean]

It has moved with me 3 times haha. Time to start using it in the lawn mower or 3 wheeler or something

 

[sledneck__11]

It has moved with me 3 times haha. Time to start using it in the lawn mower or 3 wheeler or something

I got a buncha furry fuel and my filler neck cracked on one and let it air out but my shop has smelt like race fuel for about a year so thats nice.

 

[tmo1620]

If it's sealed I bet it's still good.

Yep if leaded fuel is stored properly it is good for a very long time

 

[Modman]

It has moved with me 3 times haha. Time to start using it in the lawn mower or 3 wheeler or something

I can testify that lawnmowers don't like race gas. Here's my lawnmower on C12...LOL..... kept the bugs away though!

 

[mclean]

Hahaha same thing happened to my buddies when we used it in his lawn mower years ago

 

[tmo1620]

I can testify that lawnmowers don't like race gas. Here's my lawnmower on C12...LOL..... kept the bugs away though!
View attachment 254623

Lol there goes that idea to get rid of my av gas lol

 

[Outdoors]

Lol there goes that idea to get rid of my av gas lol

Late night piss bombs around the fire!

 

[BILTIT]

Lol there goes that idea to get rid of my av gas lol

Just dont run it straight, try 50/50. My sleds and my boat require avgas, maybe i could just take it off your hands lol.