Skid steer overheat blowing coolant

[Diesel86]

Hey all, I have a komatsu 35-1 track skid steer. Initially it would overheat after about 15 min at full work/rpm. Replaced the cooler as it was hopelessly clogged. So far replaces radiator, thermostat, rad cap, and visually inspected the water pump. Also replaced the upper radiator hose. Now it will run for 30-45 min and will start to blow coolant out the overflow. I am at a huge loss. PLEASE HELP!!

 

[farmshop]

I would look at pressure testing the cooling system. Sounds like a possible head gasket

 

[Tazza]

I would look at pressure testing the cooling system. Sounds like a possible head gasket

Bad head or gasket is the only other thing i can think of too, you have replaced or inspected everything else.

 

[Diesel86]

Bad head or gasket is the only other thing i can think of too, you have replaced or inspected everything else.

Well I just put a pressure tester on it cold and it failed miserably. But I can’t see anywhere where it’s hissing or leaking. I mean it’ll go from 14psi to nothing in less than a minute.

 

[flyerdan]

Well I just put a pressure tester on it cold and it failed miserably. But I can’t see anywhere where it’s hissing or leaking. I mean it’ll go from 14psi to nothing in less than a minute.

It sounds like it could be getting cylinder pressure into the cooling system from a bad head gasket. If the oil doesn't look milky, you might want to roll the engine over by hand a few times before trying to start it just in case the pressure testing forced some coolant into a cylinder.

 

[Tazza]

It sounds like it could be getting cylinder pressure into the cooling system from a bad head gasket. If the oil doesn't look milky, you might want to roll the engine over by hand a few times before trying to start it just in case the pressure testing forced some coolant into a cylinder.

remove the glow plugs and test it again, then spin the motor over and see if any coolant is sprayed out of a plug hole. The pressure needs to be going somewhere, if you don't see it in the oil, it has to be in the cylinders...

 

[farmshop]

remove the glow plugs and test it again, then spin the motor over and see if any coolant is sprayed out of a plug hole. The pressure needs to be going somewhere, if you don't see it in the oil, it has to be in the cylinders...

You might get a compression tester. If you find a cylinder that won’t hold a t would point to a head or gasket. You could also remove the drain plug briefly as water will be on the bottom of the pan