tractor with no thermostat?!

[George2615]

We are dealing with fact, not opinion. 50% of opinions are wrong regarding coolant moving too fast to transfer heat. Unfortunately there seems no way to reach these people with fact.
larry

I guess not

 

[Winmac]

There may well be other issues that the po hide by removing the Tstat, only way to find out is to install it and see how it works.

 

[The Fred]

Do you have a way to check the coolant temp such as a thermometer or infra red gun? You might have a faulty temp gauge. My old CASE 310 had a bad one. I found a vintage replacement on Ebay.

Once you see that the engine is running hot feel the rad for heat. You can throw some cold water on the radiator fins with the engine running it should cool right down.

I wouldn't worry one bit about the lack of thermostat until you find the actual issue, obviously a t-stat is a restrictor but for diagnosis purposes it's fine to leave it out.

Engines can overheat if the coolant is not mixed properly with water. New coolant (not pre-mixed) is very viscous and tends to not circulate well. Check the coolant for freeze point or else run plain water until the overheating is fixed.

Good luck, Fred

 

[Egon]

If the air moves fast enough it might heat things up.

 

[SPYDERLK]

Do you have a way to check the coolant temp such as a thermometer or infra red gun? You might have a faulty temp gauge. My old CASE 310 had a bad one. I found a vintage replacement on Ebay.

Once you see that the engine is running hot feel the rad for heat. You can throw some cold water on the radiator fins with the engine running it should cool right down.

I wouldn't worry one bit about the lack of thermostat until you find the actual issue, obviously a t-stat is a restrictor but for diagnosis purposes it's fine to leave it out.

Engines can overheat if the coolant is not mixed properly with water. New coolant (not pre-mixed) is very viscous and tends to not circulate well. Check the coolant for freeze point or else run plain water until the overheating is fixed.

Good luck, Fred

Good points.

.... OP - Something to check instantly. Does the system overheat but if you stop and let cool does it still have all its water. ... or does it pressurize quick when you run it and start losing water? If so its probably a head gasket or crack. Take cap off cool and start it. Does it blow bubbles?
larry

 

[Soundguy]

i'd be flow testing the rad with a garden hose too.

then after that, checking the water pump

 

[AGRIMAN]

I think Fred's suggestion is a good first step, make sure you have an overheating problem and not a faulty gauge. The temp gun is a good suggestion, but if it's running in the red as you said, you should see some steam around the cap and be able to smell that it's hot. I have replaced several of those factory temp gauges with mechanical one's as they go bad with age and the factory replacement parts are expensive.

As others have said, I suspect the problem is going to be that the radiator is not flowing the coolant as it should. I guess we all are assuming that you have blew/washed the fins out. Place your hand (or a piece of paper) in front of the radiator with the engine running. You should be able to feel the air being sucked through the radiator fins or the paper should stick to the radiator, if not then blow out the fins and check the fan shroud. Without a fan shroud, the fan will pull air from around the radiator and not through it.

Although I don't totally agree with Spyderlk, I do agree that running without a thermostat is not the cause of your engine overheating. On engines that are running wide open throttle under heavy constant load and in bad conditions, I have seen some slight improvements in cooling temps when the system is somewhat restricted over no restriction, but normally it's not enough to get worked up over.

What I usually do is take the old thermostat out and cut the tabs which basically just separates the base of the thermostat “flat washer” from the opening/closing plunger. I then put the “flat washer” part (with the restriction hole) back in and run with it, but I wouldn't hesitate to run without one either.

 

[CircleRat]

More than likely the PO took out the thermostat because it was already overheating, but the easiest way to put that to rest is to simply install the new thermostat and run it. If it stops overheating, then problem solved. If not, continue with the step-by-step diagnosis.

 

[pmsmechanic]

I could be wrong but I've read somewhere once that the purpose of a thermostat was to control water temps and slow the flow of the water through the radiator so that the air has time to cool the water flowing through the rad. I would install the thermostat and test from there.

 

[Gary Fowler]

The issue that the flowing thru the radiator to quick to cool folks should look at is this. IF it is flowing so fast thru the radiator to cool then it is also flowing thru the engine too fast to heat so it should equal out with heating vs cooling.

I have never seen the fins on a water pump wear out, just the bearings and seals so I would suspect if it isn't leaking it is ok. With a full radiator, one should be able to visually see how the water pump is flowing water via the up-swell of fluid coming from the bottom of the radiator.

I don't believe any vehicle will overheat from not having a thermostat. A plugged radiator core, either internally or externally, would be my first impression. If the OP has washed the radiator core and blown out any mud or trash then the next phase would be to flow test the core to see if it will drain thru as fast as a water hose will put it in. A trip to the radiator repair shop for a boil out or rodding of the core will likely solve the problem assuming there is a problem and not a defective gauge or sending unit.