Over heating, or I really did make a mistake

[rickyboy]

Hi again
I have a couple of 700 RMK's. I had an issue with both sleds over heating last winter. With them being liquid cooled, do they have to be ridden faster than what you might ride them ...say on a trail. Or in other words slower. My wife tends to lag behind on the trails, snapping photos and riding slow. Her sled over heated doing that. I did notice the cap on the fluid reservoir had popped and fluid was boiling over. I, then tried towing her back home when I became over heated. Lifting the hood of the machine I happened to touch/knock/brush my rad cap and it blew open, and started to boil. Needless to say it was a pain in the a$$ and had to get a ride home to purchase additional coolant. I took both sleds in to see what was wrong and the dealer had replaced the caps on both sleds. Pressure tested each and said they were both good to go. I never did get a chance to ride them again last winter so needless to say, I'm a little concerned about riding these machines slower than what some/most of you would ride them. I like speed, but the wife,.... not so much.
So again,... are these 700's more apt to over heat if run slower than say air cooled sleds.???

I posted a thread a few days ago about getting reverse and E start for these two sleds and had a great response ....thx again for that. I hope I can get some info on this issue of over heating.
Cheers.

 

[winter4ever]

They are cooled by snow and ice hitting the heat exchangers in your tunnel. So when riding on hard packed snow you should have your ice scratchers down. If you dont have any put them on. If this has been happening a lot I would be willing to bet that you fried your hifaxes as well, they require lubrication from snow as well. If you guys just do a lot of putting around like that I would recommend buying fan cooled sleds.

 

[whoisthatguy]

You can also wedge in an additional overflow bottle that catches the coolant before it spills onto the snow, just behind the coolant bottle. The coolant bottle overflow tube is inserted into the bottom of this additional bottle. When the engine gets too hot, the coolant runs in. When snow is put on the engine to cool it down, the coolant gets sucked back into the coolant system through the overflow tube. And you lose no coolant. I used a 1 quart thick flexible plastic bottle with a 1 inch diameter throat. The plastic must not melt with 220 degree temps or crack in -30 degrees below.

You can also keep the sled cool by shoveling snow onto the running boards where your feet sit. You can also kick snow onto the track, which will then spray it onto the front and rear coolers when you start moving. You should often ride briefly into the powder on the side of the trail, every couple hundred yards or until the sled cools down. The scratchers, also cause snow to be thrown up onto the track, that is then sprayed onto the front and rear coolers.

The engine will trap air in the top beneath the cylinder head cap. You must drive up on a 45 degree incline, park it, and bleed that air out of the coolant lines using an 8mm closed end wrench on the vent screw above the thermostat.

A defective water pump will also cause constant overheating. That occurs do to the nut that holds the impellar blade, backs out until the blade contacts the bottom side of the water pump cover. The blade then freezes in place and you no longer get coolant circulation. Installing a new impellar blade, a new nut and thread locking it in place, is an easy fix. Rebuilding the water pump, in not an easy fix.

 

[Dave64]

They also has a longer snowflap that came out in about 2003 or 2004 which helped their overheating issues, Ice scratchers will also help.

 

[modded93xlt]

Mainly the sleds need snow sprayed on the coolers to keep from overheating. Simple solution is get ice scratchers and ride faster... But I totally understand where you are coming from, my wife is the same and puts along down the trail. My suggestions depending on how much you want to spend would be

1.) Get digital thermostats and plumb them into the return line from the coolers, when you see the temps getting hot, find some powder to ride in for a few minutes, this will cool it down quickly. The benifit of the temp guage(KOSO makes a nice one) is that you can see the actual coolant temp.

2.) Get ice scratchers and make sure they are always down when riding on hard pack.

3.) they make a radiator kit for edge's. My buddy put one on his 700 edge X and never had an overheating problem again(down side to this is the radiator also needs air movment to be most effective, so depending on how slow she goes it might not work.

4.) swap her out to a fan cooled sled. this would eliminate the problems

I listed these in an order of benifit for the money, the temp guage is more exspensive than scratchers, but with it you can see as the sled is getting too hot and compensate accordingly, wheather that be ride fast to cool it down or have her ride in some powder for a bit.

Hope this helps the key with liquid cooled is they need the snow to spray the coolers, air temp is not enough to cool them.