oil in your ATV coolant tank?

[Charles Collins]

Have any of you guys ever found oil in your coolant overflow tank? The oil in the crankcase is clean. 

[Samuel “Sam” Frady]

If the leak is in a oil pressure galley the oil pressure would be higher than the coolant pressure so you would have oil in coolant but not the other way around. However in this case it would be in the radiator as well not just the overflow. (Radiator contents not specified in question). Also is oil disappearing over time with no smoke.

[Charles Collins]

I have to take off the front rack/bumper assembly, to open the radiator cap. But, common sense says that if it is in the tank, it is in the radiator, too. I will be taking the rack off, in the next few days, to replace the cooling fan. I will address the oil in the water issue, at this time. 

 

Thanks!

[brotho]

Sounds like bad head gasket

[Steven E]

If you can find a leak down tester , put 80lbs in cylinder at TDC and listen for leaks...look for bubbles in radiator.

[Charles Collins]

Good idea! A friend, who use to work at an ATV repair shop, told me that the oil seal behind the mechanical seal in the water pump, has probably gone out. That has been the best explanition so far, but I have not had time to pull it down. 

 

Thanks!

[gsrick]

So what did you find out?

[gsrick]

I suspect that the oil will be in both, but since the oil is lighter it will be at the top and will be the first thing pushed out of the radiator into to overflow tank.

[gsrick]

Did you notice it over heat at any time?

[Tommy K]

Head gasket

[Ahren Longo]

I would suspect the oil seal behind the H20 pump as well. Could be head gasket too though. I'm not sure if there is pressurized oil behind the H2O pump or not but I do know that there is oil pressure though the head gasket and if it ever got too hot it could damage the head gasket and the oil would leak into the coolant system. Some coolant would leak into the oil after shutdown and would collect at the top of the engine. Pull the rocker box cover and see if there's chocolatey goo in there. If there is you've got a faulty head gasket.

[Southsuicide]

head gasket bro