1981 931B Cooling question

[surferboy120]

Hi everyone,

I have a great little 1981 931B I have been using. It runs like a charm outside of the question I have. I noticed the coolant will come out of the overflow from the radiator. This means the radiator cap is seeing enough pressure that coolant is getting past and coming out of the overflow port. Dozer takes about two hours of use before I stop and let it cool down and add fluids. I did change the radiator cap to a new OEM cap and still the same. I dont see coolant in the oil and the machine runs perfectly.

Question.... Are these machine prone to getting air bubbles in the coolant system or is this a symptom of something else like thermostat or water pump? I would love to see where you guys would start given you have more experience on these old machines than myself.

Also would there be any benefit to an overflow tank for the coolant from the radiator rather than a drain line to the ground?

serial - 29Y1109

The engine is a 3204 direct injection model and the 45V31446 engine serial number is for a 3204DI

Thank you in advance.

 

[Welder Dave]

There iss something you can loosen to help bleed air but I can't remember where. If everything is in order shouldn't need an overflow tank.

 

[surferboy120]

I know there is a bleed bolt on top of the radiator but also I believe there is one elsewhere. I left my book where the machine is so I will be working on t this coming weekend to see.

 

[Welder Dave]

I think it was somewhere near where the top rad. hose attaches on the engine. Spending some time burping it could help too.