Ford 1900 cooling problems

[cgun6891]

Hi All, Im new here, but I joined to gain the benefit of all of the tractor wisdom here. I have a 1981 Ford 1900 with the 3 cyl. Shiabura diesel. It overheated last summer when brush hogging and the PRV on the coolant system blew. I hadnt noticed the temp gauge. I discovered the screen was clogged, then when I started again, I could see the water pump shaft was really floppy, so I replaced the water pump.

After hosing out the radiator and bleeding and refilling the block, I started the tractor and it didnt look like any coolant was flowing, so I disconnected the hose from the where it goes into the termostat and it wasnt pushing any water at all... what gives? I even primed the water pump to see if I could get it to pump but no dice... what am I missing?

 

[Harry in Ky]

In theory what you're describing seems pretty normal. Coolant shouldn't flow into the top radiator hose until the thermostat opens. That won't happen until it runs for a while.

 

[cgun6891]

In theory what you're describing seems pretty normal. Coolant shouldn't flow into the top radiator hose until the thermostat opens. That won't happen until it runs for a while.

I probably should remove the thermostat and see if it is siezed up....

 

[Harry in Ky]

No, you should run it awhile and see if it opens on it's own. There may well be nothing wrong with it.

 

[cgun6891]

No, you should run it awhile and see if it opens on it's own. There may well be nothing wrong with it.

I thought it was fine but this afyernoon I took it out to plow and about 15 minutes in, it started dumping coolant out its overflow like it was boiling coolant... might need a full phosphoric acid flush maybe?

 

[Harry in Ky]

The Japanese small diesel engine designs have many advantages in general. Unfortunately, they are not very forgiving when overheated to much of a degree. Your history of running a bush hog with a plugged radiator AND a possibly faulty water pump at the same time, running it until it blew out the radiator cap puts things into questionable territory. Replacing the thermostat and a professional radiator flush/test service MAY be of help, but it's also possible you now have a head/ head gasket issue coming on.

That said, how full did you fill the radiator? I don't think it has any sort of coolant recovery tank so excess coolant will escape by any means available until the level is down to a comfortable point. With the system full and the coolant cold it should be visible above the tubes but well below the filler neck. The liquid need room for expansion when things heat up.