B7800 over heating?

[Rob 80]

Tractor will over heat if used for more than 15 min even if it's just idling. radiator is full and the radiator fan spins, screen is also clean.

Any other ideas as to why it's over heating? Has around 300 hrs on it.

 

[BeauGeste]

Failed water/coolant pump? Happened to me.

 

[Rob 80]

Failed water/coolant pump? Happened to me.

Is there a easy way to find out? This is a friends tractor.

 

[milkman]

Also, stuff gets through the screen, remove the screen and use a light to look through the radiator fins especially at the bottom of the radiator. May have to remove the radiator shroud to check it.

 

[ovrszd]

Crank it up. Have access to the radiator hoses. When gauge says it's hot is the top radiator hose hot? How about the bottom hose?

If top radiator hose stays cool the thermostat isn't opening.

If top radiator hose gets hot but bottom hose stays cool then water pump isn't circulating coolant.

If both hoses are hot then gauge is faulty.

 

[Thomas]

Check air filter etc. for the heck of it.

 

[Jim Nelson]

Tractor will over heat if used for more than 15 min even if it's just idling. radiator is full and the radiator fan spins, screen is also clean.

Any other ideas as to why it's over heating? Has around 300 hrs on it.

The only time I have over heated mine was mowing reeds and cat tails with a rear mount mower and the fluff from the cat tails plugged the radiator. I was watching the screen and keeping it clean but the build up in the radiator got me. I cleaned it up with compressed air then the pressure washer.

 

[Leejohn]

Best way to check water pump is to check and see if water is dripping on the bottom side. Then remove belt and check for movement in the shaft. That is after you checked belt and cleaned the radiator, next would be the thermostat. After all that then you well have to go for a head gasket or cracked head.

 

[JWR]

Crank it up. Have access to the radiator hoses. When gauge says it's hot is the top radiator hose hot? How about the bottom hose?

If top radiator hose stays cool the thermostat isn't opening.

If top radiator hose gets hot but bottom hose stays cool then water pump isn't circulating coolant.

If both hoses are hot then gauge is faulty.

OVERSZD has it 100% covered. Just do as he said.

 

[kuboman]

Don't forget that the radiator can be plugged up inside which will give you a hot top hose and cold bottom hose.

 

[ovrszd]

Don't forget that the radiator can be plugged up inside which will give you a hot top hose and cold bottom hose.

Yep. On a high hours older tractor that is a consideration. In this case, with only 300hrs on it, much less likely.

 

[kuboman]

Yep. On a high hours older tractor that is a consideration. In this case, with only 300hrs on it, much less likely.

Unless incompatible antifreeze were mixed and or poor quality water.

 

[4570Man]

I'd wash out the radiator first. If you don't resolve the issue I'd be checking the temperature with another set of gauges. I don't think my tractor's would overheat with a mostly plugged radiator idling. Especially inside of 15 minutes.

 

[ovrszd]

I'd wash out the radiator first. If you don't resolve the issue I'd be checking the temperature with another set of gauges. I don't think my tractor's would overheat with a mostly plugged radiator idling. Especially inside of 15 minutes.

Yep. To overheat in 15 minutes means a "closed" system. No circulation.