Ford 6610, too much radiator pressure

[mikewood869]

Our 1982 Ford 6610 is putting out too much radiator pressure and is just blowing it out of the overflow tube after a 1/2 hour or 45 minutes at pto rpm of run time. After 6 hours of run time, I had to add a 3/4 of a gallon to get the coolant level at the top of the cores. I was thinking that the tractor needed a new thermostat, but when I pulled off the thermostat cover, there was no thermostat in there. I put a 188 in for giggles and now the tractor will start blowing coolant, that takes 10 to 15 minutes or less of pto rpm to start releasing coolant. The fan belt is tight, the water pump doesn't have play in it, I put a different radiator cap on it (there was a 13 psi cap so I tried a 16 psi that I had lying around), and that didn't work. There's also not that many bubbles when you first fire up and watch the coolant move around in the radiator. There is no water in the oil, but there is oil in the radiator (the radiator cap builds up oil). Would it be time to do a head gasket again or do I need to get something tested? There is a good amount of blow by and if you plug up the valve cover breather tube, it will shoot out a paper towel fast.

 

[derwen1959]

Could it be head gasket or worn cylinders or could
it be same problem as ford digger further down this
List and that is porous block which ford had a bad
reputation for

 

[paul]

I’d be worried about the ports block deal.

Paul

 

[mikewood869]

The what?

 

[mikewood869]

I hope not. It hasn't hydro locked yet. We just had this thing split last month.

 

[David G]

Water will only expand so far, if it keep blowing then something else is doing it.

I would suspect a combustion leak.

 

[mikewood869]

(quoted from post at 11:28:40 09/22/20) Water will only expand so far, if it keep blowing then something else is doing it.

I would suspect a combustion leak.

Any other easier way of telling where its leaking from without having to pull it apart?

 

[hurleyjd]

Looks like you have tried everything but one thing and it is what I would do. Either buy a new radiator or take you old one to a reputable radiator shop and have it rodded out. That might just solve your problem.

 

[sotxbill]

Fill radiator to very top,,, and look for bubbles while its running... keep adding a bit of water if you need to, to keep it at neck...

if you keep seeing bubbles, you have a problem, blown head gasket, cracked head.....

If no bubbles... check for good water flow when thermostat is open... Get an ir gun and check for a 20 degree drop between top of radiator and bottom of radiator to show correct flow and proper cooling..

Also some of the engines in the later models required a double ended thermostat or they would overheat. These engines had the huge bypass between the thermostat housing and water pump that the bottom of the thermostat had to close this bypass, otherwise the water would simply bypass and not go through the radiator correctly. I dont know if you have that later model or not that is on later the 7710 II series. These tractors would run cool until forced to work hard and then overheat with a normal thermostat.

 

[hurleyjd]

Water pumps vanes can be completely gone and the shaft still be tight. Can you see movement of water when the engine is running there should be a surge when the thermostat opens. You observe this with cap off and looking in the top of the radiator.