DK 55 Turbo overheating issue

[Coyote machine]

My neighbor bought a used '07 DK55 Turbo which has 518 hours on it now. He's had it about a year, since last Spring.
It started overheating when our first big storm hit earlier this winter and his original radiator was damaged.
After going through two bogus (defective from factory units), he finally has a working radiator. Now it will run fine at idle all day long. When put under load the temp gauge spikes but returns to normal after a while. He's wondering if the T-stat is bad or if he has head gasket issues, because he says there seems to be a lot of air in the system. I think he's got exhaust gases from the engine blowing by the head gasket into the cooling system causing his spikes in temp and the 'air' he says is apparent.

I'm less familiar with testing for exhaust in coolant in diesels than with gas engines, so any experienced insight would be appreciated. Does a coolant overflow tank pressure tester render the results needed by showing excess pressure in the coolant overflow?

Any other thoughts/ ideas/ solutions?

Thx.

 

[LaVoie Equipment]

The quickest and easiest test is to remove the thermostat, heat water on your stove to 180 - 190 and see if thermostat opens.

Have you thought about your water pump? Is it turning - internally?

From there you will need to check compression. Pull a glow plug and use proper adapter.

It may be best to take to your local dealer if you are unsure or do not have the proper test equipment.

Tony

 

[MichiganIron]

Two ways to check for the warning signs of a bad head gasket:

With the tractor cool, open the radiator cap. Make sure the coolant is full to the top and start the tractor for a few seconds. Observe whether there is coolant bubbling from the radiator.

With the radiator cap replaced, start the tractor and let it warm up. Note the color of the exhaust. After a few minutes of warm up, the exhaust should be clear. Make note of any white colored exhaust.

These are the easiest field tests for coolant in the combustion chamber. If you have a bad head gasket, you will probably note bubbling coolant and white exhaust smoke.

 

[Coyote machine]

Thanks for your replies. I've passed them along to the owner. He is flatbedding it to his dealer tomorrow.
We're both thinking head gasket. It overflows the radiator with the t-stat removed, so I suspect the exhaust gases are getting into the coolant.

 

[charleyfarmall]

Double check that the radiator isn't packed with dirt...

 

[Coyote machine]

Double check that the radiator isn't packed with dirt...

My original post:
...his original radiator was damaged.
After going through two bogus (defective from factory units), he finally has a working radiator. Now it will run fine at idle all day long.....

Sorry Charlie, guess you missed that part

Tractor is at dealer awaiting outcome- thanks for your reply.

 

[Coyote machine]

UPDATE: The tractor has a blown head gasket and is being repaired by the local dealer. Waiting on further results...