XP overheating problem

[Visi]

This last summer I installed a new crank. After the rebuild my squish is about .054/.055. I am running three gallons of 110 per tank with a SLP head, Full SLP exhaust, SLP intake, and Trygstad Porting. I jetted supper conservative with 560 mains. On my first ride out I got about a mile and a half down the icy trail and it started overheating with the scratchers down. I pulled to the side of the trail and loaded the heat ex-changer with snow and waited for it to cool down. Waited about 15 min. and started back up the trail. about 300 yards it started overheating again and went into limp mode. I told the guys to keep going and went back to the truck. That night I emptied the gas out of the tank because it was about three months old and put new gas in. I also took out my thermostat. The next day I unloaded and warmed the sled up for about five minutes. Went down the trail at a different spot. The trail was groomed and had ok snow. The motor overheated again and went into limp mode. This time the rear heat ex-changer wasn't even hot. Again I went back to the truck. When I got the sled home I fabbed up a system to flush out the heat ex-changers. Nothing came out of the ex-changers. Now I am worried that my Water pump went out or I had too much of the LOCTITE-5910 and it got into the water jackets. I can pull the motor apart and get it back together in about a week but I really don't want to unless it is necessary. Anyone have any idea about what else could be going wrong. Thanks, I know it got lengthy.

 

[wayfst]

thermostat

 

[powerkeg]

Are you sure the engine was overheating? I have heard of people not having a good connection at the ground strap and for some reason causing the gauge to read an overtemp. Do you have a plug and play in line with your thermostat cause if the resistor is bad in that it will screw up your temp readings.

 

[islanddoo]

Had a similar problem with my 860 first time out. Not enough oil in the water pump cavity at start-up. Stripped out water pump gear, also when this happens no oil pump probably worth checking out. Easy to tell if you have any flow though, look into reservoir and you should be able to see some flow from the small tube.

 

[Red-eye]

air lock?

 

[Visi]

I took out the thermostat between rides. I will check on the ground connection. When I add antifreeze to the sled I use a hoist on the front of the sled and make sure it is higher than the back of the rear ex-changer. I did get some air bubbles back into the over flow last night after I blew out the ex-changers but no water was coming back from the line out of the head like it was when I fired it up for the first time. If the water pump gear is stripped do I just get a new gear or how do I go about it? The sled is set up for premix, do I add oil to the water pump before installing crank?

 

[Red-eye]

I took out the thermostat between rides. I will check on the ground connection. When I add antifreeze to the sled I use a hoist on the front of the sled and make sure it is higher than the back of the rear ex-changer. I did get some air bubbles back into the over flow last night after I blew out the ex-changers but no water was coming back from the line out of the head like it was when I fired it up for the first time. If the water pump gear is stripped do I just get a new gear or how do I go about it? The sled is set up for premix, do I add oil to the water pump before installing crank?

Fill the cavity while you have the engine out.

 

[Visi]

Great, I have some work to do then it sounds like. Thanks for the input. I appreciate it.

 

[islanddoo]

You have to replace the entire water pump shaft from skidoo around $200. Basically fill the cavity with oil with the motor upside down. Install water pump shaft and cover. You need a reservoir of sorts from the vent tube above the oil pump or where it was filled with oil to make sure oil is there always.

 

[Visi]

I have the race department set up for oiling the crank. I just didn't fill it first. I guess you live and learn. I just took the top end off and have the bottom end sitting on the work bench. I will get try and get it going this week if I can get the parts. Thanks for the help. I will make sure it's full this time.

 

[Visi]

Tonight I took the crankcase apart. I was looking at the water pump gearing and it looks good. There are no signs of wear on the gear. While I was spinning the gear it looked to me like the shaft was spinning inside the bearings closest to where the oil pump was, then it would reach a certain point and it would catch and you could see the balls in the bearing move a little and then release as the shaft turned. I didn't have a chance to see if the crank was not reaching the gearing either. Tomorrow I will take the water pump housing off and put the crank back in and spin the crank and see if the propeller spins. I will also check to see if the gearing on the crank is spinning too. Any other ideas guys? I will post pictures tomorrow.

 

[Visi]

Has anyone heard of an air bubble getting into the line from the oil delete reservoir causing the water pump/motor to overheat?

 

[portgrinder]

youre not circulating man. nothing should overheat in 300yards.

It takes a long time to get all the air out of a system, even with no t-stat. i've done it way too many times

did you put the right elbows in to replace the t-stat housing? you need a 1 inch 90 to go fromthe head line back to the coolers and then i think its a 1/2 to 3/4 90 to go from the resevoir to the line that goes down to the front of the engine.

 

[Visi]

Thanks man. I got it figured. The propeller is spinning on the water pump shaft.