Yellow waxy material in radiator reservoir of my Kubota RTV 900

[Gary Fowler]

I hadn't looked at my radiator fluid level since last summer so I thought I had better check it for freeze temp. I opened up the overflow reservoir and the top had a yellow greasy/waxy substance all around the neck and on the suction hose. It has swelled the hose to the point that it just fell off the top. I managed to fish it out and reverse the hose and the bottom half wasn't swelled from the oily, greasy yellow substance. It hasn't has the fluid changed since new but it still showed good to as high as my gauge went (-40) but it was a bit rusty orange looking. I bought some Prestone today to change it out with as soon as we get some decent weather. I just don't know what the yellow gunk was. Any one ever see this stuff. I suppose it could have been some kind of algae but it sure looked just like soft margarine. I have never put anything in the radiator not even water and it was clean last summer.

 

[Diamondpilot]

I hadn't looked at my radiator fluid level since last summer so I thought I had better check it for freeze temp. I opened up the overflow reservoir and the top had a yellow greasy/waxy substance all around the neck and on the suction hose. It has swelled the hose to the point that it just fell off the top. I managed to fish it out and reverse the hose and the bottom half wasn't swelled from the oily, greasy yellow substance. It hasn't has the fluid changed since new but it still showed good to as high as my gauge went (-40) but it was a bit rusty orange looking. I bought some Prestone today to change it out with as soon as we get some decent weather. I just don't know what the yellow gunk was. Any one ever see this stuff. I suppose it could have been some kind of algae but it sure looked just like soft margarine. I have never put anything in the radiator not even water and it was clean last summer.

Does the radiator have a cooler for say the tranny or power steering? Reason I ask is both my father's Corvette and my friends Cadillac have both had the transmission cooler fail in them. My father got lucky and the tranny fluid went into the rad. Mt buddy not so lucky with the caddy. It pumped the coolant into the tranny and cost $4000 to fix.

Do some investigation.

Chris

 

[Gary Fowler]

Does the radiator have a cooler for say the tranny or power steering? Reason I ask is both my father's Corvette and my friends Cadillac have both had the transmission cooler fail in them. My father got lucky and the tranny fluid went into the rad. Mt buddy not so lucky with the caddy. It pumped the coolant into the tranny and cost $4000 to fix.

Do some investigation.

Chris

Thanks for the insight. I will do a bit more looking at the problem. I plan to change out the anti-freeze. The RTV has the radiator stuffed in up under the seat and it is hard to see what all it tied into it. I didn't think to check the transmission oil. I will do that also.