'05 Summit 800 overheating help

[skidoochick564]

I'm hoping you guys can give me some ideas here. I bought a '05 summit 800 with a 159" track from a friend, and everything had been great with it til our last ride out. It was on a fairly warm day, on hard packed trail, and the temp light came on about a mile up the trail. I was leading my mom and a friend who don't sled much, so I couldn't ride off the trail through the trees to get more snow in the track. Still I tried to get off in the powder where I could. Well, a couple miles later it completely overheated, white steam coming out everywhere, and I thought the thing blew up. Turns out the antifreeze just boiled over and made a horrible mess so we towed it back to the parking lot and the ride for that day was over.

Now, the sled used to have a 144" track and went to a 159" so it's definitly not a trail sled and I'd attribute overheating to the bad snow conditions and what we were riding that day. The heat exchangers haven't been extended so I know most of the snow isn't even reaching them when it gets thrown up by the track. But a couple weeks ago we rode into town on hard packed trails and the temp light never even came on. Does this sound like a thermostat issue or just a bad snow conditions deal?

I did find a longer snowflap and have put that on, and have also considered installing ice scratchers. I've also tossed around the idea of extending the heat exchangers but that looks like it involves a lot of fabrication work and I'm not sure how practical this is. Has anyone else had these kind of issues when going to a longer track?

 

[MARCUSO]

I had some heating issues with my summit also. It was definitely the snowflap, My suspension was dropped a couple of inches and the snow juts flew out the back.
Scratchers are important also. They keep the sliders lubed and also the coolers get some snow.
Sometimes just working the sled while going up in elevation heats it up, as opposed to coming down the trail.... or riding on flat ground.

I would think you should be ok with the shorter cooler.

 

[Tackbtch]

Thermostat

I have had issues with the stat on my 02 and 06. Both failed and caused like symptoms. I have deleted the stat on both sleds. The 02 is now gone but we ran it like this for two seasons with not a single issue, the 06 is on its second season with no stat. Just have to warm up the sled before any wot is done. Very seldom do we over heat on marginal snow, we also run scratchers when on low snow or icey trails. Like your sled the 02 went from a 151 to a 159 with no mods to the cooler or snow flap. I am a firm believer in no stat on the doos. Dino

 

[Impatientforsnow]

you may want to do a compression test done the motor the rings may be going bad if they have not been replaced yet the 05 was a bad year for this..

 

[bikerjustin]

Last Friday my friend and I went out in poor snow conditions as well looking for shed moose horns. Because this was our mission and not riding we were riding extremely slow and there was no powder snow to be found from the recent warm temps. I had the ice scratchers down but still there was hardly any snow being thrown up to the cooler. My temp light came on repeatedly and I was getting coolant boil out from the reservoir. I just sped the sled up to a higher speed and got some cool air through to the motor and I was fine. I think most people will shut the sled down and throw snow on the cooler which won't do any good because coolant is not circulating with the motor shut off.

You have to remember that these mountain sleds are not designed to stay cool riding trails, the cooling system relies on powder snow getting to the cooler to keep water temps normal. If these Summits were meant for trail riding there would be a fan on the cooler.

Ice scratchers will certainly help lube the hyfax and potentially get snow to the cooler but they need powder and fresh air.

 

[MARCUSO]

Last Friday my friend and I went out in poor snow conditions as well looking for shed moose horns. Because this was our mission and not riding we were riding extremely slow and there was no powder snow to be found from the recent warm temps. I had the ice scratchers down but still there was hardly any snow being thrown up to the cooler. My temp light came on repeatedly and I was getting coolant boil out from the reservoir. I just sped the sled up to a higher speed and got some cool air through to the motor and I was fine. I think most people will shut the sled down and throw snow on the cooler which won't do any good because coolant is not circulating with the motor shut off.

You have to remember that these mountain sleds are not designed to stay cool riding trails, the cooling system relies on powder snow getting to the cooler to keep water temps normal. If these Summits were meant for trail riding there would be a fan on the cooler.

Ice scratchers will certainly help lube the hyfax and potentially get snow to the cooler but they need powder and fresh air.

Yes I agree with you, but I think the benefits of a faster speed would be more stuff getting thrown on the coolers, rather than the wind blowing.. The majority of trail sleds are water cooled also.

 

[AKtoad]

thermostate delete should help also the low to mid range always runs hot because they are usauly the leanest. If you give it some quick burst of throttle and spool the water pump up and flood the cylinders with gas to cool the combustion chamber it will also help. All of this is no replacement for snow though so I trick I learned to keep the sled cool on the way to good stuff in the spring is: Get a milk crate and put it on the back of the sled and fill it with as much snow and ice you can find at the truck, when on the trail the holes in the bottom of the crate will feed the cooler with cold snow, then when you do get to the good spring snow take off the crate and pick it up on the way out to refill for the ride to the truck. Works like a champ