Ski-Doo Snowmobiles Forum banner
1 - 20 of 21 Posts

·
Registered
Joined
·
30 Posts
Uhh... 2018 850 etec with 3k locked up.

20 miles and 2 hrs into trip, water temp was 105F.

Stopped for 30 seconds, started it and took off at a 15 mph clip. 20 feet later it beeped and flashed "rev limit" then immediate power loss and I slapped the killswitch.

Locked up with maybe 10° rock back and forth. Took out the motor today and found a broken oil line which I guessed was the problem on the way home.

However the burned, melted, caught on fire with soot on the case surprised the hell out of me.

What the hell happened??!?!?
 

Attachments

·
Registered
Joined
·
30 Posts
Discussion Starter · #3 ·
I've seen this . It was on a summit that was over heated on trail up 2-3 times .
I had my scratchers down and the hottest it got all day was 135. Shouldn't the PTO oil feed have failed first? Unless the rod and inner bearing failed and got very hot then the oil line burned.
 

·
Registered
Joined
·
6,132 Posts
There have been a few threads about this in the trail section. It's caused from exhaust heat.

Bob
 

·
Banshee Builder
2022 backcountryXRS // 2019 BC 850- 16,238miles traded
Joined
·
8,569 Posts
ouch! sorry bout your luck man, out of warranty?
 

·
Registered
Joined
·
6,132 Posts
How was the oil lines under the plastic shield up under the exhaust? They are melting and cracking. You definitely had a fire.

Bob
 

·
Registered
Joined
·
30 Posts
Discussion Starter · #11 ·
How was the oil lines under the plastic shield up under the exhaust? They are melting and cracking. You definitely had a fire.

Bob
I know this line caught on fire under the motor, but how?

The water pump line next to the Y-pipe was fine, the MAG rod feed line was fine next to the fire.

Any ideas on HOW these 3 inches under the motor - away from the y-pipe - caught fire and the other rod feed thats half an inch away was fine?

Prevention methods? Do I build a heat shield mounted to the bulkhead under the Y pipe and heat tape the y pipe?
 

·
Registered
Joined
·
49 Posts
My 2018 summit electric start with just over 500 miles burned 10" off the oil lines under the motor & seized the motor with one day left on the warranty! They also replaced the starter & starter cable which also lead me to think the cable or starter maybe shorted out got hot & started the oil lines on fire? Dealer tried to say it was my fault because of the Grip N Rip bulk head kit that I installed but nothing comes nowhere near the burnt lines. Skidoo went good on the whole repair. Then I took the heat exchanger out 1/2 way through the second break in :blink: $5500.oo insurance claim! Bad luck sled but I Love the motor and the way the chassis responds.
 

·
Registered
Joined
·
471 Posts
I know this line caught on fire under the motor, but how?

The water pump line next to the Y-pipe was fine, the MAG rod feed line was fine next to the fire.

Any ideas on HOW these 3 inches under the motor - away from the y-pipe - caught fire and the other rod feed thats half an inch away was fine?

Prevention methods? Do I build a heat shield mounted to the bulkhead under the Y pipe and heat tape the y pipe?
Oil leak or fuel leak that caught fire under that specific area? Any low spots right under that area that might have allowed something flammable to pool up? Or, some fluid leaking from above and catching fire in that area? Brake fluid all good? It is flammable...
 

·
Registered
Joined
·
30 Posts
Discussion Starter · #16 ·
Oil leak or fuel leak that caught fire under that specific area? Any low spots right under that area that might have allowed something flammable to pool up? Or, some fluid leaking from above and catching fire in that area? Brake fluid all good? It is flammable...
ill check my brakes....

Can you check the injectors for leaks . Could of had fuel leak down there .
im going to order all new o-rings for all fuel system stuff.

i do recall a burning smell about 5minutes before it locked up but i thought it was the belt.

UPDATE: Ordered a new motor and am replacing all the oil lines with 450F degree oil line and sleeving with 1000F ceramic or fiberglass sleeving. Will also be wrapping Y pipe and top section of pipe, along with a new exhaust donut.
 

·
Premium Member
Joined
·
28,393 Posts
I got lucky and found a thread for a melted oil line. It's a different line, the one that feeds to the center cavity for the coolant pump shaft. Note the oil line melted underneath the protective sheathing and the sheathing itself survived. I don't know how or if it will help, but I hope it does because I'm not sure that wrapping the y-pipe is such a good idea. Before you do this I strongly recommend asking a reputable pipe builder for the 850 about the temperature effects on for the portion of the mix that gets scavenged back into the combustion chamber. Kevin Cameron wrote briefly about this in an article for CycleWorld (click here) and in a Dynotech Research article regarding detonation: "back pump mixture from the header pipe that has picked up too much heat (this is why nobody heat wraps header pipes anymore)." (click here).

The person I think that you could speak to is [email protected] (Grip N Rip Racing). He understands the requirement for ventilation on the 850 and the path for air flow. For example the first oem brace had no ventilation slot.

In the thread linked below, note how close the oil line for the center cavity is to the y-pipe.

Melting oil line beneath factory heat sheilding from oil resvoir to cr
Started By MACH1/Z, Jan 08 2020 02:21 PM
https://www.dootalk.com/forums/topic/1577551-melting-oil-line-beneath-factory-heat-sheilding-from-oil-resvoir-to-cr/
 

·
Registered
Joined
·
611 Posts
Wondering if the finned clutches are pulling air from the exhaust area? I have the front brp bulkhead brace that's solid, thinking of drilling some vent holes in it now.

Sent from my SM-G960W using Tapatalk
 

·
Vendor
Joined
·
95 Posts
Hey Utah-Doo-Doo, thanks for reaching out. We're sorry to hear of what happened with your unit and really hope no one was hurt. BRP takes safety very seriously and we would like to get an opportunity to find out more about what happened so we can ensure to build even safer vehicles in the future. Please email us to [email protected] with your VIN number, and a reference to this forum, or to your username. We are looking forward to hearing from you. Talk soon, Vanessa-BRPcare
 
1 - 20 of 21 Posts
Top