ENGINE GETS RED HOT

[CharlieS]

But, but, more coolant is moving around. Each pass picks up less but there are more passes???

This may be irrelevant but on my truck installing a thermostat with too large an orifice will ensure that the temperature gauge never leaves the cold pin and if it's cold out I'm even colder and trying to see through a frosted up windshield.

Empirical observations!

More coolant is moving, but the temp of the coolant being transfered from the radiator to the block is not as low with no tstat installed.
Thermostat = restriction which means the coolant has more cooldown time in the radiator, thus its a cooler temp when mixing/replacing the coolant in an engine.
The thermostat is nothing more than an automatic tempratiure sensing valve that opens when it senses too much heat, and closes when it senses not enough heat.

In your truck scenerio, i suspect there are other forces that come into play, however in any liquid cooled engine scenerio, too large of a radiator, for example, will make the coolant hard to heat to operating temp in cold weather, as will having the improper tstat installed. volume of liquid transfer from the water pump is a factor, diamater if hoses connecting block to radiator, or even a partial heater core blockage. An effecient cooling system is a well engineered package, not just any radiator, hooked up to any old engine. Too much total coolant capacity is as ineffecient as not enough coolant capacity. Radiator design is also important, in that how many square inches of cooling surface in how many rows of transfer tubes, whether its a cross flow, or vertical flow design and i'm sure other factors are involved.
These also would apply to any common liquid cooled engine design regardless of application.

 

[Egon]

temp of the coolant being transfered from the radiator to the block is not as low with no tstat installed.

Agreed on that but as there is no restriction the coolant flow is higher is it not.

Now on my truck as soon as we got a Thermostat with a smaller bypass orifice installed the engine warmed up, the windshield defrosted and I became much warmer.:thumbsup:

 

[rjkobbeman]

A thermostat is designed to keep an engine warm, not cool. If you remove the thermostat, your engine will run cool.

At some point, as outside temps get high enough, I imagine the thermostat stays open -- which would be like no thermostat installed.

 

[FredH]

Although A full open thermostat is allowing flow it is not the same amount of flow that no thermostat would allow , thus giving the the coolant time to cool as it passes through the radiator . Try pulling a long grade with a heavy load or even a heavy trailer first with a thermostat then with-out .


If thermostats were not required , why would virtually every type motorized vehicle have them ? It is not like they are making money on a $3 or $4 part .
But as I mentioned before , a brand new $4 thermostat almost stranded a $40,000+ boat .

Back to the thread though , I would start simple as my first suggestion , i.e. the coolant mixture percentage . Next check thermostat , 1) is it working , ( simply put into a pan of boiling water by suspending from a piece of wire ) , 2) Is it installed correctly ? Next would water pump, not only is it functioning but is the gasket installed correctly ?

Fred H.

 

[Wayne_H]

Nonsense! Think about that for a while and then explain it to me.

Easy, the water does not spend enough time in the radiator to cool off.... It is an age old problem, old mechanics know it well.

Wayne

 

[Egon]

Easy, the water does not spend enough time in the radiator to cool off....

But doesn't it make more passes and all those little increments from each pass add up.

 

[Jim Thompson]

I'm certainly no expert on this, but, it seems to me that the question is one of efficiency. Certainly you have increased volume with no thermostat installed and the coolant would pass through the radiator more times but it would also pass through the engine more times thus gaining heat with each pass. Without the ability to efficiently dissipate the newly acquired heat, it seems to me that you could reasonably expect a net increase in heat with each pass - thus overheating.

I am well aware the people frequently removed the thermostat from engines in the 40s and 50s with seemingly no adverse effect. I also would not place a large wager, one way or the other, that at some point that they didn't encounter heating problems associated with that action. For those of us who remember those years, people also were known to run only water with no coolant. Knew a fellow with a couple of John Deere LAs who replaced the coolant with oil until he could replace a leaking head gasket.:laughing:

 

[user.69169]

Well now gents this here thread sure wnet both up and downriver, and the fellow who started it still has the problem.

I gotta figure the red hot description was a little off cause the pistons would sure as heck lock up before the block got that hot. Back when we run alcohol for antifreeze it was pretty dang common for an engine that hadn't run in a while to run hotter than hades when she first got going again, and every dang time it was cause of all the accumulation of rust that looked like cornflakes in all the water passages. Of course if a fellow didn't like his job and was fixin to quit he could clean out a few ashtrays in a choke & puke and put about 2 handfulls of filters that he busted open into the return hose and then start that truck up and cook an engine in a few miles. I've seen it done where the temperature gague didn't even go up cause there weren't no water around the sensor probe. I've seen guys who loaded them cigarette filters into the fuel filters too, and that is one mess.

Now if that was my engine first thing I'd do would be drain all the coolant and set it aside. Then I'd hook a garden hose up to the bottom engine drain and get water flowing just so it was trickling out the top of the radiator and start the engine up. Once you get her running you turn the hose off and let the engine get hot. You probably best clamp off the heater hoses when yo do this cause you don't want the crud plugging the heater core.
Once she gets hot you open the hose up and watch the crud & crap flow out top of the radiator. Yu do this a couple times and that engine got itself a clean cooling system.

Far as thermostats go, back when I started driving trucks didn't come with heaters. I had to pay an extra fifty dollars to get a heater in my Diamond T pickup back when I bought it. Them trucks didn't have thermostats cause they didn't need to get hot enough to heat the cab. Thermostats open and close at a set temperature to keep the engine running at that temperature probably some for efficiency and some for to have hot water going through the heater core.

 

[doall]

open station tractors don't have heaters, but they do have thermostats for a reason. I used to wrench for a living, take a thermostat out; sooner or later it'll run hot. The water is not cooling if it just flows straight through the radiator. The engine is way hotter that the radiator is cool in a short time.

 

[Egon]

If'n you got a big radiator wouldn't the distributed flow in the radiator be quite a bit slower than in a very small radiator?

 

[user.69169]

open station tractors don't have heaters, but they do have thermostats for a reason. I used to wrench for a living, take a thermostat out; sooner or later it'll run hot. The water is not cooling if it just flows straight through the radiator. The engine is way hotter that the radiator is cool in a short time.

Don't much matter what you used to do, shoot I used to be a fireman on a Diesel locomotive, that dont make me smart enough to lay track or work a switchtower.

You say "take a thermostat out; sooner or later it'll run hot" and I say yer full of it! A thermostat aint a whole lot different from a light switch, they both turn things on and off. A thermostat turns coolant flow on and off to the radiator and the light switch turns electric on and off to the lightbulb.

Now when we get to Diesel engines, that thermostat sits there closed till the engine gets up to a good operating temperature and keeps the engine at that temperature by either starting or stopping coolant passing through the radiator. Diesels is a lot more sensitive to operating temperature than gas engines are.

My experience both driving and being around Diesels is a heck of a lot of them get hot because the water passaged in the engine load up with crud that prevents the coolant from passing through. Then again I only been at this since we covered the nose of the truck with a tarp or cardboard sign so the dang truck would get up to good running temperature in winter and the alcohol cooked out of so you had to carry a couple gallon of Zerex. You come up to Wisconsin pulling 18 axles with 100,000# on top in January driving a truck that normall runs in Georgia and you get to learning real quick. I been told most of that crud in them engine passages is from people putting bad water in the cooling system, but I can't prove one way or the other.

 

[irwin]

I'm really surprised that this thread has turned into a thermostat theory discussion. The fact is a t/stat exists get an engine warmed up and to keep the engine at a constant temp. once it warms up, so that the engine will run more efficiently. In my 30 years working on engines for a living I've never heard of an overheating engine because the stat was removed...

Now I'll admit I don't know everything, so there might be an engine that will do that.. just haven't heard of it. The rarity of this engine will pretty much negate the possiblity that the OP has this problem.

Remove the thermostat and the engine stays cooler.... unless there are outside factors, ie: ambient temp is very high.. radiator is clogged up.. head gasket failure...cracked head..coolant passages in engine are clogged... radiator fan is bad, etc. and even with these other factors the restriction of a thermostat will make the overheating worse.

The OP needs to get to where his tractor is and see for himself what's going on. then he can come back here and fill us in.

 

[Just Bill]

Hello
This thread has made for some interesting reading.
There appears to be a split of about 50/50 in opinions.
I personally keep the thermostat in place and have had my share of trouble with them over the years.
I don't know when they were first used but I know they have been used since the 50s and probably longer.
They have never been improved and the same problems have always been there.
It doesn't make sense for that one item to have so much control over whether an engine lives or dies. Your chance to intervene doesn't last very long.
To prove your point, how about a few of the people that know that thermostats are not needed, pull them out and take a short drive.
About a 20 mile round trip should be enough to give you the info you want and you can post the results.
Its probably available but I haven't been able to find any info supporting leaving a thermostat out for any reason.
Who is willing to prove their point and provide facts and not just an opinion?

 

[doall]

Don't much matter what you used to do, shoot I used to be a fireman on a Diesel locomotive, that dont make me smart enough to lay track or work a switchtower.

You say "take a thermostat out; sooner or later it'll run hot" and I say yer full of it! A thermostat aint a whole lot different from a light switch, they both turn things on and off. A thermostat turns coolant flow on and off to the radiator and the light switch turns electric on and off to the lightbulb.

Now when we get to Diesel engines, that thermostat sits there closed till the engine gets up to a good operating temperature and keeps the engine at that temperature by either starting or stopping coolant passing through the radiator. Diesels is a lot more sensitive to operating temperature than gas engines are.

My experience both driving and being around Diesels is a heck of a lot of them get hot because the water passaged in the engine load up with crud that prevents the coolant from passing through. Then again I only been at this since we covered the nose of the truck with a tarp or cardboard sign so the dang truck would get up to good running temperature in winter and the alcohol cooked out of so you had to carry a couple gallon of Zerex. You come up to Wisconsin pulling 18 axles with 100,000# on top in January driving a truck that normall runs in Georgia and you get to learning real quick. I been told most of that crud in them engine passages is from people putting bad water in the cooling system, but I can't prove one way or the other.

you're probably right, it didn't make you smart enough. But being a mechanic is directly related to the statement I was making. I didn't say I could build the roads.

 

[Jim in ICT]

I always assumed that the people that designed the engine (gas or diesel) knew more about it than I did. I stay with the t-stat in the block.
Buy a new t-stat &gasket.
Use 50/50 antifreeze/water mix.
Clean the radiator fins & screens and flush the block before filling.
Check for collapsed hoses.
Check that the fan's pushing air through the radiator.
Make sure that there's no air trapped in the top of the block or cyl. head by allowing the system to cycle several times while running.

If you're still heating up, see a mechanic to test for oil in the coolant, or coolant in the oil and pressure test the system.

 

[works4me]

Throwing my 2 Cents in, I wonder if it is the hard working Deisel engines that mainly overheat without a thermostat?

Maybe the excess cooling capacity is less than Automotive engines??

 

[Egon]

Ah-someone once had a plugged rad and the engine overheated. Pulled the thermostat and the engine still overheated. It was the beginning of a new urban myth!:thumbsup::laughing:

Don't think I could even find the thermostat on the car let alone remove it. Think with todays engine controls taking it out would send the computer brain into a frenzy.:laughing:

 

[irwin]

Here'a a quote from this site.. How an Engine Thermostat Works

Engine Thermostat

When a thermostat malfunctions it can stick in the closed position not allowing the coolant to circulate, causing the engine to overheat. This will cause the vehicle to overheat in a very short amount of time (about 5 minutes). Or the thermostat could stick open causing the engine to run too cold. In this case the service or check engine soon light could illuminate, followed by a trouble code. To test a thermostat remove unit. Prepare a pan of water deep enough to cover the thermostat completely. Next install a temperature gauge into the water along with the thermostat. A cooking thermometer works well for this. Next, start heating the water while watching gauge, the thermostat should remain closed until the water reaches 190ｰ at this point the thermostat should start opening and be completely open at about 195ｰ. If the thermostat stays closed through the boiling point the thermostat has failed and needs replacing. If the thermostat is stuck open or broken it has failed and needs replacing. Never run an engine without a thermostat because the thermostat works as a system flow regulator as well. What this means is the thermostat has a specific opening that regulates the flow through the cooling system. If the coolant is allowed to flow too quickly through the radiator the coolant will not have time to transfer the heat it has absorbed. This will cause the engine to overheat.

I doubt the tractor in question would be overheating this quickly for this reason.

Now that it's settled let's see what the OP has to say.

 

[Egon]

If the coolant is allowed to flow too quickly through the radiator the coolant will not have time to transfer the heat it has absorbed. This will cause the engine to overheat.

Sure wish my truck understood this. If the wrong thermostat with a larger orifice is installed it just will not heat up, Brr in the winter.

 

[Ford tractor]

Hey all...I have a problem and question I'd like to pose to you all...I have a 1992 MF1250 w/ a E3AD1 Iseki engine. We recently overhauled it with all new parts; had pump sent off to PA for a professional overhaul and then after everything was put back together, I ended up in the hospital and didn't get to hear the first startup. My brother and friend, however, did and they said it got red hot almost immediately. They think it's the water pump. What do you guys think? At least, it's been in my garage, out of the weather for the last couple years. Oh, I almost forgot, I had the radiator completely overhauled too. Please help...thanks

First, what does that mean? "it got red hot" It could mean that the exhaust manifold got literally red hot from a stuck open fuel injector. It could mean that the coolant started to steam / boil from a bad water pump. It could mean the T-stat was put in upside down (a VERY common mistake). It "could" mean nearly anything --> even that it was running so good it was "red hot"!

Please add more detail and I'm sure the people here can figure it out.

Ford Tractor