[thunder66]

I just got around to putting my 800 back together. It seems to run fine but I can't seem to get the cooling system to "burp" if you will. I've only managed to get it to take 1 gallon of coolant and it should ultimately except another 7 or 8/10ths of a gallon if I'm not mistaken. I've had both ends of the sled elevated, I've run the sled for up to 5 minutes with cap on and even cap off but the reservoir is still showing full. Anyone know any tricks to getting the air pocket out? Thanks ahead of time for any responses!

 

[xcrsp440]

That sure seems like a lot of coolant. My 600 held just a bit over a gallon when I had the engine out.

 

[thunder66]

From the manual...

600 MXZ 5.42 L 1.43 G
600 Ren 5.77 L 1.52 G
800 MXZ 6.12 L 1.62 G
800 Ren 6.47 L 1.71 G

 

[Thumb2bar]

With the cap off, sled running, are you seeing circulation of coolant? Is there a stream of coolant entering reservoir bottle? When you say full rebuild, what did you do? Did you drain block/motor from hose fitting off water pump outlet?

 

[thunder66]

With the cap off, sled running, are you seeing circulation of coolant? Is there a stream of coolant entering reservoir bottle? When you say full rebuild, what did you do? Did you drain block/motor from hose fitting off water pump outlet?

Yes, the coolant was drained from the fitting in front of the water pump. The engine was out of the sled and the coolant completely drained. New crank, monoblock and pistons. I'm not sure I'm seeing coolant moving in the reservoir but I don't recall seeing that in the past.

edit: I am wondering about the thermostat at this point. If it won't open I believe what I am experiencing would be the result.

 

[Mill]

Yes, the coolant was drained from the fitting in front of the water pump. The engine was out of the sled and the coolant completely drained. New crank, monoblock and pistons. I'm not sure I'm seeing coolant moving in the reservoir but I don't recall seeing that in the past.

edit: I am wondering about the thermostat at this point. If it won't open I believe what I am experiencing would be the result.

Running it for 5 mins won't work.

Take the thermostat out, reconnect it back and run it so the coolant flows throughout the system unobstructed.

I wouldn't want to run it without fluid in the block.

Lift the front of the sled while burping it.

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[thunder66]

Running it for 5 mins won't work.

Take the thermostat out, reconnect it back and run it so the coolant flows throughout the system unobstructed.

Lift the front of the sled while burping it.

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That's what I'm about to do. They could've have put the thermostat in an easier to get to location!

 

[Daag44]

It's not all that easy to see the coolant flowing into the bottle. It flows from the top hose, the one below the vent hose. As the coolant flows through the system the air constantly bleeds out of this hose into the bottle.

 

[DOOLIFE800]

Just did the top end on my 800 E-Tec. 2016 XRS. I also had to weld my heat exchanger at the rear so I had to completely flush that out and dry it before welding. I had to disconnect those hoses under the gas tank that feed the heat exchanger. How do you know that you got everything out of the heat exchanger? Maybe if you pick the rear of the sled way up. I can't believe you have to pull the thermostat out to bleed the system. Do you have access to a manual. If not I can take a picture of mine with the procedure. I did prefill my heat exchanger before installing the hoses so I never did do a full system bleed. But I did measure what I put in and it was exactly what the manual said.

 

[thunder66]

Just did the top end on my 800 E-Tec. 2016 XRS. I also had to weld my heat exchanger at the rear so I had to completely flush that out and dry it before welding. I had to disconnect those hoses under the gas tank that feed the heat exchanger. How do you know that you got everything out of the heat exchanger? Maybe if you pick the rear of the sled way up. I can't believe you have to pull the thermostat out to bleed the system. Do you have access to a manual. If not I can take a picture of mine with the procedure. I did prefill my heat exchanger before installing the hoses so I never did do a full system bleed. But I did measure what I put in and it was exactly what the manual said.

I don't know that I got everything out of the heat exchanger when I took it apart but I am confident that more than 8/10s of a gallon came out of the sled when I drained it and that is all I've been able to add. I'm thinking about the T stat because I'm wondering if it is stuck after sitting dry for months. I'm not thinking of taking it out to bleed the system, i'm thinking of taking it out to see if it is functional or not. I have a manual yes. You said that you put in the amount called out in the manual which is 6.47 Litres or 1.7 Gallons. Before I cut the 4 oetiker clamps to get the T stat out I'm going to put the pipe and muffler back on it and let it run while observing the reservoir closely to see if fluid is in fact circulating. I don't think it is but I am not sure so I'll pay close attention this time.

 

[Brptech]

You can try a Vacuum brake bleeder on it seal at the cap it will suck there air out of it make sure you have water pump Rotation ie The worm gear is not striped

 

[Thumb2bar]

You can try a Vacuum brake bleeder on it seal at the cap it will suck there air out of it make sure you have water pump Rotation ie The worm gear is not striped

That was going to be the next step if he confirmed no circulation into bottle. Sadly it is a common problem after rebuilds and need more emphasis from suppliers to consumers. Those gears need to mesh!

 

[sledhead_24_7]

Something to try.

Elevate the front to higher than the rear, that will allow the air to be pushed out of the heat exchanger to the motor where you can bleed it out or leave the radiator cap off, for a few.


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[Daag44]

Raise the rear to allow any air pocket to reach the rear of the heat exchanger, then raise the front to allow the air pocket to reach the coolant bottle. Whatever sequence is used - front to back or back to front - after a couple of times any significant air pocket should have dissipated into the coolant bottle. Air is constantly entering the cooling system and being purged while riding.

Sorry, I meant to raise the front and tilt the sled like mxzx700trygstadmod mentioned a few posts further to fill the heat exchangers.

 

[DTXRSB]

Use an Airlift. Worth it, esp if you work on your own vehicles, etc.

 

[12/3]

Raising the front has always worked for me...

 

[mxzx700trygstadmod]

Tip the sled up on it's side with the coolant bottle on the high side. That usually provides enough angle to let air pockets rise to the bottle. I usually have the sled running and tip it up with the bottle on the high side and with coolant cap off until it burps . Add more coolant as needed until cold full and repeat process as it may burp more than once. That has always worked for me anyway.

 

[adrenalator8]

So while it's running is the exchanger getting warm.?? if it heats up the system is circulating as it should. take it for a short run let it cool down and then check your level!