Tractor Experts....... need advice here......

[The Poultry Peanut]

Quote:

 

[mjdtexan]

Picture it this way.

there are two parts of water in a tractor (any water cooled engine really). One part is in the engine. The other part is in the radiator. The thermostat is in the middle. When the water in the engine gets to be a certain tempature (dictated by the thermostat) the thermostat will open and the water in the engine will go into the radiator and the water that was in the radiator will now go into the engine. The water that was in the radiator has been in there a little while and has had a chance to cool off.

Now

If there is no thermostat (or if there is a defective one) then water just keeps flowing and never stays in the radiator long enough to have cooled off and you wind up with an engine that overheats.

Did that make since?

Always have a thermostat. They are cheap most the time anyway.

In short, the thermostat allows you to excange hot water for cold water. Always run antifreeze too, even in summer, it transfers heat better than just water.

 

[rebelcowboysnb]

Ive heard that argument many times but the truth is that after the water speed passes a minimum flow rate the heat transfer rate stays the same an in most cases goes up as the speed of the water increases. Lets say a set amount of water stays in the radiator for 10 seconds each round an loses 10 BTUs of heat in that time. If you make the water move twice as fast it will stay in the radiator half as long each time but go threw twice as much. It will spend 5 seconds in the radiator an lose 5 BTUs each time around but because it travels threw the radiator twice as much it still it sill loses the same BTUs over the same amount of time. Its just like saying that if the wind blows fast enough it wont make contact with your skin long enough to cool your body. We all know that is not true. I have see hundreds of cars, trucks, tractors an equipment run fine without a thermostat an most times they run colder. If it is running hot it is most likely not the lack of a thermostat, something else is going on. That mith was started because there are a few cars over the years that the thermostat deflected the water to flow one way threw a engine an if it is not there the water will sit still in some of those water ports an that part of the engine will over heat.
Dodge made a V8 that was one of those engines in the last 10 years.

General rule when anything over heats is to check the fan, then the fan belt, then the water pump then the radiator cap pressure test, then check that the water is moving in the radiator an that there is no bubbles in then water. If that seems ok pull the thermostat an see if it runs cold. Somewhere in that will find the issue. If it runs hot after all that the radiator needs checked an cleaned.

It is always better to have a thermostat but it is almost never needed to keep the engine cold.

 

[mjdtexan]

Quote:
I've had them run hot while a thermostat was not in them and then run cool like they are supposed to when I put the thermostat in. Our experiances may be different but I am fairly certain that the thermostat is in there for a good reason, ¿que no?

 

[Tala]

Well I just got a $6.99 thermostat for my truck. It runs ok without it, it has always almost over-cooled anyway, ---- but in a car the heater doesn't work very well without a thermostat and it's pretty dang cold outside!

Anyway, point is that they are CHEAP as parts go, so if it makes ya feel better why not just buy one??

 

[rebelcowboysnb]

It does 2 thing. It helps create back pressure to help dislodge trapped air pockets in the block. And it brings the engine up to operating temperature an regulates it at that point. that give you inside heat an it makes the engine run at it optimum. What it does not do is restrict flow or regulate water speed after the water reaches a temp above what it is set to unless it gets to cold. Water speed is regulated by water pump pulley size.

It needs replaced but it is not the issue, it is someones (rigged)attempt at a fix for the issue.