Recently had to weld up a hole in my cooling rail. I can’t find much on how to properly flush cooling system. Any help would be appreciated. Thanks
How to flush cooling system
- Thread starter TallCan
- Start date
N
I've done this about 3 times due to contaminated coolant caused by a bad head gasket but anyways this is what I do.
Remove exhaust pipe along with exhaust silencer.
Suck out as much coolant as you can in your coolant bottle. A shop vac works good. Next put something like a plastic bin of what not under neath your sled.
Loosen the hose clamp off to the inlet of the water pumping housing. Coolant will come out instantly. Have your shop vac ready.
Next take the hose going into your thermostat off.
Now with everything disconnected someone a buddy or set up a rig and lift the back of the sled up. Even more coolant will come out all the coolant that's in the tunnel.
Next I leave both hoses disconnected but put the cap back.on the coolant bottle and I know blow air through through the hose that came off the thermostat. This will push any remainder of coolant out of your system.
Now do the reverse. Install all.the clamps and fill the system with coolant with the front end of the sled lifted up. It will purge out most of the air itself but not all of it. You know you've done it right if your use almost 6 litres of new coolant.. next run the sled with with the cap on and use the bleeder screw on the thermostat housing. And that's all. You may need to top up after a ride or two.
I've done it this way 3 times with no air locks of over heating issues.
Good luck.
Remove exhaust pipe along with exhaust silencer.
Suck out as much coolant as you can in your coolant bottle. A shop vac works good. Next put something like a plastic bin of what not under neath your sled.
Loosen the hose clamp off to the inlet of the water pumping housing. Coolant will come out instantly. Have your shop vac ready.
Next take the hose going into your thermostat off.
Now with everything disconnected someone a buddy or set up a rig and lift the back of the sled up. Even more coolant will come out all the coolant that's in the tunnel.
Next I leave both hoses disconnected but put the cap back.on the coolant bottle and I know blow air through through the hose that came off the thermostat. This will push any remainder of coolant out of your system.
Now do the reverse. Install all.the clamps and fill the system with coolant with the front end of the sled lifted up. It will purge out most of the air itself but not all of it. You know you've done it right if your use almost 6 litres of new coolant.. next run the sled with with the cap on and use the bleeder screw on the thermostat housing. And that's all. You may need to top up after a ride or two.
I've done it this way 3 times with no air locks of over heating issues.
Good luck.
Northshore hit it pretty well, I'll just add that I'll loosen all the main hose clamps I can get to, and then with the shop vac on the expansion tank I'll loosen the other hoses enough to introduce air to the system. That way you can suck a pretty good chunk of coolant out, once you find the right hose to disconnect. After I've got most of the coolant out, I'll suction every hose I can get to individually.
I did a full flush and refill on my sled a year or so ago, and I'm pretty sure you can't get more than 90% or so of the coolant out without dismantling everything. So, if you really want to flush all the old stuff out you'll want to fill with water a couple times and run it enough to cycle it through the whole system. That shouldn't be at all necessary in your case though, and you don't want to do it if the sled is somewhere that it could freeze – I just mention it for the case of badly contaminated coolant. If you're just doing a drain and fill, all you have to do is make sure you've got the right anti-freeze mix and get the nose up in the air to help burp the system.
I did a full flush and refill on my sled a year or so ago, and I'm pretty sure you can't get more than 90% or so of the coolant out without dismantling everything. So, if you really want to flush all the old stuff out you'll want to fill with water a couple times and run it enough to cycle it through the whole system. That shouldn't be at all necessary in your case though, and you don't want to do it if the sled is somewhere that it could freeze – I just mention it for the case of badly contaminated coolant. If you're just doing a drain and fill, all you have to do is make sure you've got the right anti-freeze mix and get the nose up in the air to help burp the system.
Just outta curiosity ... how big of shop vacs are you guys using? I'm doing the top end on an Axys for the first time and am having hell getting all the coolant sucked out with my 6.0HP Craftsman shop vac. I don't recall having this much trouble on the Pro RMKs?
V
Mine is a 12 gallon Shop-Vac.
I just talked about this the other day on the 850 forum. Sounds like a lot of excess work. Just remove the 2 screws holding down the thermostat housing and remove the thermostat. Put the hose end, with housing still connected, into a bucket. Then set your shop vac to blow instead of suck. Put an old t-shirt or green scrubbie other filter over the end of the shop vac hose and blow straight into the engine. All of the coolant will come flying out of the hose/housing end. If your shop vac is squeaky clean, you won't need a filter on the hose.
