Stuck themostat: I think?

[PastureKing]

In my less than 12 posts, this is the first that I have attempted to attach a photo.

If you see the photo, it is a thermostat from my JD950, which has been overheating. I replaced the water pump and thermostat last year, but it is again overheating this year. The thermostat that I replaced last year... appeared just as this one does, with the rod extended out and to a ~120 degree angle.

It seems to be stuck, but I don't know enough to know if this is normal, if it is stuck open or stuck mostly closed.

Finally, what are the cons for running my tractor without the thermostat until a new one arrives. I need to do cut a pasture soon.

Thanks

 

[Midniteoyl]

You have the right thermostat? There appears to be some kind of damage to the stat and I can only think that its because its the wrong one.. Or installed wrong.

You can run all you want in the warm months without a thermostat.. just let it warm up a few extra minutes before running hard.

 

[TractorTech]

It is definitely stuck open. Just because it was a year ago that you replaced it doesn't mean it can't be at fault. It is either a bad design or poorly made.
The thermostat acts by trapping hot water in the radiator long enough to let it expel excessive heat. Meantime, cooler water warms up to pre-determined temperature of thermostat until hot enough to open. Without the thermostat, the water continuously heats up until the system overheats.
Go to an auto parts store and try to match up with an import model thermostat if a direct cross reference is not available. It will get you going for now.

 

[Baby Grand]

<snip>

Without the thermostat, the water continuously heats up until the system overheats.

<snip>

With a stuck closed thermostat, yes. Without the thermostat, or with a stuck open thermostat, the coolant will flow through the radiator continuously, resulting in a cooler operating temperature. Not such a problem in hot weather, but something you need to fix before it gets cool/cold, or your engine will never "warm up".

 

[PastureKing]

It is a genuine JD part from the JD retailer. It can only be installed one direction.

I'm going to see how long it runs without overheating now.

 

[sd455dan]

In my less than 12 posts, this is the first that I have attempted to attach a photo.

If you see the photo, it is a thermostat from my JD950, which has been overheating. I replaced the water pump and thermostat last year, but it is again overheating this year. The thermostat that I replaced last year... appeared just as this one does, with the rod extended out and to a ~120 degree angle.

It seems to be stuck, but I don't know enough to know if this is normal, if it is stuck open or stuck mostly closed.

Finally, what are the cons for running my tractor without the thermostat until a new one arrives. I need to do cut a pasture soon.

Thanks

That thermostat is not only (stuck WIDE OPEN) it looks to be hyper extended or damaged, throw it away and install a new one...

The spring side always goes toward the cylinder block / or head... Good luck.

 

[RobJ]

With a stuck closed thermostat, yes. Without the thermostat, or with a stuck open thermostat, the coolant will flow through the radiator continuously, resulting in a cooler operating temperature. Not such a problem in hot weather, but something you need to fix before it gets cool/cold, or your engine will never "warm up".

Actually in certain conditions yes without one could cause overheating. It helps to regulate the water flow through the radiator. It's primary purpose is to maintain a constant engine operating temp, which is better for your engine. Stuck open and you may not notice it right away, closed and you will soon.

 

[ovrszd]

That thermostat is definitely bent. I can't even figure out how it could get bent like that??? I'm curious to hear the answer for this problem.

 

[mfreund]

Actually in certain conditions yes without one could cause overheating. It helps to regulate the water flow through the radiator. It's primary purpose is to maintain a constant engine operating temp, which is better for your engine. Stuck open and you may not notice it right away, closed and you will soon.

How could no thermostat cause overheating?? No thermostat would cause engine to run cold, could not cause overheating.

 

[Clint S]

How could no thermostat cause overheating?? No thermostat would cause engine to run cold, could not cause overheating.

Like he said it helps regulate the flow of water through the radiator by causing resistance. In some instances running without a stat will cause the fluid to circulate too fast. It will not stay in the radiator long enough to cool.
T stats, like said above are to get the engine up to operating temperature and keep the engine running in a temp range. If it's too cold they close, but if it's too hot they open and stay open . If you have cooling issue not running a stat or running a cooler one will not prevent or fix the issue. It will just take longer for the overheat to happen.