[David Anthony]

About to replace my head gasket in the 95 vmax. While taking the head off i obviously lost a lot of coolant. When I get the new gasket and put it back together how should I go about adding coolant back in? How do you do this without creating airbubbles in the system?

 

[Coolhand]

You need to pop the pressure cap off and fill it and the overflow bottle to full. Then lift the front end up as high as you can get it. Then run it at idle while the air dissipates. You have air in the system already so the only way is to let it idle and slowly come out of the pressure cap. Just like in a car when you change the radiator, you leave the cap off and as it warms up the levels drop as the air leaves the system. But with it being liquid cooled and having radiators/exchangers on the tunnel the front end must be higher then those. Best way to do it is to run it on a hill or a snowmobile trailer with the front tilted up some. Or use a jack and get it as high as the jack will go.

 

[David Anthony]

Thanks for the help!

 

[snowmoer]

There are also bolts that can be removed at the rear heat exchanger. You have to remove the seat to get to them. You pick the front of the sled up like Coolhand is talking about. Remove the bolts and start to fill with coolant. When the coolant starts coming out of the holes, put the bolts back in. Then, keep filling until full. Start it up to burp the air out of the system.

When you take it out for a ride, you will need to add more coolant. Even though I could not get any more air out of the system on my 96 in the shop, I had to add coolant to the overflow bottle a few times. There were still air bubbles hiding in there that only riding it would bring out.

 

[David Anthony]

When filling it with the front lifted do you fill through the overflow bottle or the pressure cap?

 

[Coolhand]

Fill both to their fill points. Coolant bottle should say full when hot or cold. IIRC Mine does but its a Polaris. Just lift that front end up as high as you can get it and leave the cap off. Over time with it idling and hitting the throttle now and then so it don't load up of course the air will dissipate from the system.

 

[kccats]

Fill through cap and have sled running and warmed up and as high as you can.

 

[snowmoer]

I filled through the cap. When I was on the trail with the sled warm, I would then just top off the bottle and it would get sucked into the system. But getting all the air out in the shop is the best.