I cannot understand the condesending nature of your posts. I only wanted an indepth reasoning to your post after reading your answer it seemed as if you could provide it. I was considering going ahead and changeing the thermostat to stock after you made some points, $10 part and some time no big deal. Maybe as an engineer you see only black/white. Many things fall into the gray area and work. If you were to say hey if you use anything below 180 degree your engine will eat itself to death in 5 years then maybe someone is gonna listen, but if someone has been running their engine without a thermostat for the past 20 years without the first problem, your giving them a hard pill to swallow even if you are right. I could argue that adding a cam is going to throw the efficiency of your motor way off and you should not do it, but if you just gained 20hp you are gonna care less, true. The last example happens all the time. You see where I am coming from? This is a forum everyone puts in their two cents worth and everyone forms their own opinion, right or wrong. Don't misunderstand I appreciated your indepth answer and would like them in the future.

 

Sorry, I am getting tired of defending my information from everyone with a cousin that runs with no thermostat etc etc. I have never run an engine without a thermostat because I know better. But I have seen and worked on engines that did. They were cantankerous beasts that had to be tuned to run rich, sucked gas like pigs, fouled plugs, and had detonation problems from all of the carbon deposits, etc etc etc. Some of the owners even liked how they ran. Now of course some of these guys are going to tell you their engines run "just fine" for 20 years, but they would probably think that fuel magnets, tornado venturi devices, and straight pipes make their trucks run better too.

Nothing is black and white and there are plenty of gray areas. There are many things that "work" today or even for years but are not right or even close to it.

All I ask is that people do their homework and check out the information at the library, from the SAE, and here on the boards from qualified sources.

For a start read SAE publication #HS-40/91, principles of engine cooling systems... Available from SAE ($50 for 49 pages) and possibly some large technical, or university libraries. I do not own a copy so all I can do is tell you what I read years ago in that or similar publications. The updated version is listed above.

You can find some limited information on automotive "tech info" pages. Many of them will flat out tell you not to run without a thermostat for many reasons. Unfortunately they do not give detailed reasons, you will need to read the many SAE publications for that.

 

Thats the whole idea behind these sites is so that you can direct people or provide them with info they are not going to find otherwise. Oh well again I appreciate your response and plan on getting the correct thermostat just to be on the safe side.

 

Well, i just have to jump in here, sorry i didnt find this discussion earlier. I agree mostly with Bronco351.

I do always run a thermostat- but i am from Kansas City, where it does get cold in the winter- so i do believe in using the stat. And it is always a 160. The experience i have is from running these stats over the last 15 years, the last two years or so in my 96 Ranger 4.0.

Before that, growing up our 1948 John Deere "B" had no thermostat and always run 140 degrees, 150 if you really ran it wide open- i think we all already know how long running and how reliable J.D. tractors are! My model B is now a 1937 model, still does just fine and no stat.

Since this was my first EFI and computer equipped motor (my 96 Ranger- i even tried a 180 stat. The engine simply doesnt run as well. The gas mileage only improved 1 mpg from stock. Put in the 160 and presto! no more pinging, detonation, back firing- and a 4 mpg improvement from stock.

Here is my theory. I always also run electric fans. With a thermostat AND an electric fan- the stat is closed, and the fan is off when the engine is warming up- this condition allows it to warm up as quickly as possible- to get it out of open loop. Closed loop is 160 degrees, and you can verify this by going to www.slpengineering.com If you run a 160 stat, your water temp is going to be 170 degrees- i believe, just like Bronco351, that is the highest your water temp should ever get. Think about it- 170 degrees is actually very hot- be assured, there wont be acids forming. 170 degree water is plenty hot enough to get rid of any acids, just like it would get rid of the acid/oil in your driveway in fast order! I simply dont agree with the SAE guy- i use my own personal experience- i had a GMC S-15, 2.8 V-6 years ago. These engines were quite famous for blowing head gaskets, pinging, detonating, running very poorly. I checked the compression oon mine before i bought it- it was factory normal. After the 160 stat, electric fan, and radiator from a 4.3- ran like a champ!

Also 160 stats means your oil doesnt turn black nearly as fast, and the a/c blows far colder (If the underhood temp is around 230 vs. 170- your a/c just wont be nearly as good)

I suggest you actually install a 160 stat, and make sure your engine is running 170 degrees (i use mechanical water temp gauge #2333 from Auto Meter) check your gas mileage before and after- and just see yourself. Myself and Bronco351 have done this - and you see our report on doing it. The other poster hasnt even installed or ever used a 160 stat- i have for 15 years- let alone Bronco351. Now you can let us all know what you are going to do- J.D., KCK

 

This has been a pretty good discussion thus far.
Just a couple of questions. Why would researchers and engineers, of all car companies, put a thermostat in their cars and trucks, if they really didn't need one? Like was mentioned previously, a thermostat also helps warm an engine up faster and keep it warm in the winter by not letting water pass as quickly, thus you get heat from your heater. With a 4-row radiator I even use a blanket on mine in the winter to get a warm engine faster. I live in west TX and it gets pretty hot here also, but it gets cold too. I could see not having a thermostat in the summer, but never in the winter. Personally I wouldn't. I've also heard some people say running without a thermostat causes engines to overheat due to the constant flow, and the fluid doesn't have sufficient time to cool while passing through the radiator. (grant it this is not always going to be the case with every engine) Sort-of how an AC won't cool if the coolant doesn't have time to dissipate the heat from the inside coil to the exterior coil.
Please, no yelling! It's just another 2 cents.

 

This is a good discussion, i enjoy it, and i promise i wont be the one to start any yelling.

The manufacturers primary concern is to get vehicles sold efficiently and cheaply. They mostly run 195 stats, imho, because they have to sell a vehicle equipped to run in Alaska as well as southern AZ. And they also mostly use mechanical fans, which are cheaper then electric fans and put out slightly more cooling effect.

If you run a 160 stat and you want heat in the winter- you are going to need an electric fan- which doesnt come on until the engine is hot- 170 degrees in my case. By the time the fan comes on- i already have plenty of heat. But if you run electric fans- even flex a lite's excellent Black Majic- you are going to need a bigger radiator then stock to keep your truck cool if you also use a/c and the temp is up around 100, which it is here in KCK.

Also 195 stats are a cheap way to meet emissions rules, again, esp when you are using a mechanical fan. Notice how Toyota and Honda, known for quite reliable vehicles- also use mostly 180 stats, not 195?? They take the time to fine tune the motor and meet emissions even with a 180 stat. 160 stats would be even better- but remember their vehicles have to run in Alaska too.

Basically- you as the owner of the vehicle have to fine tune it to work in the environment you use it in. And for most environments and with a broad range of temps- they run better with 160 stats, bigger radiators and electric fans. my 2 cents, but curious what others think. J.D., KCK

 

We seem to have 2 parallel threads going here

https://www.ford-trucks.com/forums/s...hreadid=143205

 

Yeah we do, I didn't know if you looked on this site very much as I remember you like to talk about the 300, so I set up a new topic as bait. haha.

Well fellows I am about to test the theory (to some degree) weather or not the higher thermostat (higher than what I have now) makes any difference (usually someone would post the opposite wouldn't they?) using the stock recommended thermostat which is the 195 in my case. I am sure I will be posting questions about how my engine pings and the da*n thing won't start because of heat soak but what the he** i'm a gonna do it. I remember now why I thought the lower stat was a good idea, I was having trouble starting it hot, I installed the phenolic spacer and still had some problems but at this point I have a new HD radiator and covered the lines with heat tape as well an pulled them away from the block so hopefully the above were the solution and not the lower thermostat. Blah blah blah, I will let you all know something shortly

 

Torque1st, I agree completly with everything you are trying to get across to this guy. As a mechanic, I have seen many times where someone will not take your explanation as fact, but because JoeBob down the street says it works, it must be correct. If anything, its job security.

 

I have presented the facts that I have remembered from my research on the subject. I never did mention what SAE stands for, I assumed people would know. SAE == Society of Automotive Engineers. The SAE is the standards body that automotive engineers, manufacturers, and researchers work thru to disseminate the bast FACTS and research that is available. I don't know of any better source for FACTUAL information than that.

If someone has run a 160 stat for years and not had any "trouble", I am sure their "empirical data" is much better than hundreds of thousands of hours of specially instrumented research both in the lab and in the field, with all sorts of chemical and microscopic testing available. -The "color of the oil and the AC blows colder", -what a crock of BS.

Listen up guys... RUN THE FACTORY RECOMMENDED THERMOSTAT IN YOUR ENGINES!!! Absolutely NEVER run without one!!! -Unless of course you feel you are somehow smarter than 75 years of the cumulative efforts of thousands of Engineers and Scientists that work with these systems daily. Technology has changed and what may have "(barely kinda maybe) worked" 20 years ago is simply not acceptable today.

At the very MOST vary the temperature +/-10F from the factory recommendations due to climatic extremes. That DOES NOT apply to Kansas City, -I know I live there.

NASCAR engines run without a thermostat, they run a restrictor ring instead to modulate the flow of fluid thru the engine, -a special application under specific known heat loads. They change restrictors based on track temperatures etc.

The flow rate thru the radiator DOES influence the heat transfer rate. There is an optimum rate under certain conditions and the engineers working with computer simulations, instruments, and test engines have determined those rates. But then some people are smarter than all of that.

What you are saying about acids in oils and temperatures just does not make any sense no mater how someone "thinks about it". You are obviously not a chemist or you would know better.

Again "closed loop" is just an engine management computer setpoint that is used on some engines" that has no meaning in this topic. What does SLP Engineering have to do with the SAE and this conversation. They are an English Engineering construction company. Very strange reference??? A 1937/48 tractor motor does not have much to do with modern engines or engineering practice either.

As far as not running a 160 stat... Of that I am guilty but then I don't have to jump off a skyscraper either to know it is a very dumb idea. I have worked on engines with no stats and low temp stats and I CAN report accurately on the conditions I found in those engines.

I am done, I am thru arguing with ignorance and empiricle seat of the pants "data" from laymen with no scientific education... At some point you just have to let them baffle each other with BS!

 

Hey T-1st, some of us do appreciate the great info you share. Please don't hold back any of that valuable knowledge because of a few people in the minority that is just doing what they believe works for them. Who knows what contributing factor makes it work? If it weren't for people like you guys with different opinions, guys like me wouldn't learn near as much. From listening to your rantings, and others on this very subject is where I learned to blanket my radiator in the cold to maintain the same operating temp year round. Thanks! I learn more from finding threads like these than posting questions myself.

 

I still do not understand the tone of your post's. In one of your posts you said all you could do is teach others, and so on. You have missed one thing to teach you have to have the ability to get your point across. Just by ending your post the way you have you will set others off and then you will have taught nothing, and others (the one's who get pissed by the tone of the post) with refuse to even consider what you have wrote, be it the truth or not (human nature).

The other post were the mention of not using a thermostat and/or using one as low as 160* falls into the GRAY area. Will it cause the engine to form acids that will deteriorate the engine, sure, but it also works for these people in the sense they achieve what they want and that is to not overheat their vehicle, if that is their decision, so what, you stated all you could.

Hey I read what you posted and apparently it made sense to me, my decision was not made only because of what you said. You mentioned something that I and others probably were not familiar with, I searched everywhere I could and gathered info compared it to yours and here I am I bought the d**n thermostat and hope to have it in shortly. I could run the thermostat at 160* get a little better air temperature in the intake or up the thermostat to the 195* and try and keep the motor as clean as possible, being as this vehicle is not driven often, this layman knows that is bad on a motor right off the bat so I opted for the latter, good choice huh. I was only going to let people know how the switch to the higher thermostat would affect my startup after the engine is warm as everyone knows that using edelbrock intake/carb it is possible to get heat soak. As stated before I think you have something to offer everyone as far as in depth technical support, it is the delivery, actually the final comments I cannot understand.

 

I'm breathing deeply so I don't turn this into a flame!! Let me start off by saying, Torque 1st, for an administrator you are acting very child-ish. I think it's because us laymen have put up some very good arguments against yours, that must really frustrate you.

Now back on the subject.

YES, I do think I'm smarter than those scientists that do all that research in LABS. The reason I'm smarter is simple, I actually work on cars. I don;t sit in an office with a white coat on poking at chemicals. I'm in the garage getting greasy, and turning wrenches.

I forgot who stated that running with no thermostat creates too much flow through the radiator that, causes the fluid not to dissapate heat. This is a OLD wives tale. A cooling system acts on chain reactions. If the fluid in the radiator isn't moving (thermostat close/ open) fast enough, the fluid in the block also isn;t moving very fast. Which causes the fluid in the block to sit in one place WAY too long and create heat spots and possibly boil the fluid. If you don;t believe me go to any HIGH-Performance engine shop. They will are tell you the faster you get the coolant moving the cooler your engine will run!!!

Now as for NASCAR. The reason Nascar puts restriction plates in the cooling system is quite simple. They run very big water jackets throughout they're engiens. The purpose of the restriction plate is to create a small amount of pressure in the cooling system to keep the fluid moving properly.

The reason our cars/trucks don't have this problem when the thermostate is removed is because our cars/trucks use small water jackets/sharp bends in the water jackets, which casues coolant system pressure.

Now, the only time I use/suggest not to use a thermostat is in the peak summer months. In Arizona this is in JULY. Here in July the temp. can easily soar above 112*. Since I do heavy off-roading, and stop and go traffic. If it wasn't for no thermostat my engien would over-heat.
The rest of the year I run a 160* thermostat which keeps the cooling problems under control!!

I bet you I ****** off torque 1st again!!!

 

Well, i am with you on this Bronco351, and i am not a kid either, having run no stat myself (only in our 1937 and 1948 john deeres though) and 160 stats for 15 years. And i believe the principle is the same with j.d.'s and the newer motors. J.D. sure got a huge reputation for exceptional reliability and i believe it wasnt a coincidence their watertemp is always around 140 or 150 degrees. And since your Bronco is carbureted, and you are running with no stat in the summer heat- i can surely understand it. You want the coolant to circulate- it IS already hot!

This IS my first EFI equipped vehicle with 160 stat. But i have 20,000 miles so far, never any pinging, gas mileage increase of 3 mpg., plugs are not black from over rich condition, no check engine light on. There is every sign that the engine is going to have a very long life, just like the GMC S-15 with the 160 stat before it did. And i believe in the 160 stat enough that i am willing to run the truck 10 years so i can find out. Thanks for your input- J.D., KCK

 

Where do you guys get the idea that cooler is better? It is not. The more heat the engine rejects to the water jacket, the less power it makes. the cooler the water jacket is, the more heat it will reject. Simple thermodynamics. It's admittedly easier to tune an engine to run at a lower temperature, the window for error is wider on things like detonation, but modern EFI systems have taken care of that pretty well. The engine is going to deliver better power, better economyans fewer emissions at 180°F than at 160°F.

Also on the issue of oil color. The fact that the oil color doesn't change at 160°F indicates that the oil is not doing it's job. Oil does 3 things: lubricates, cools, and carries away contaminants. The color change is an indication of how well it is doing the latter.

On the issue of flow through a radiator, Heat exchangers require a certain residence time of the fluid in the exchanger to reject heat to atmosphere. If you pump the fluid through too quickly, it won't give up the heat

FWIW they're engineers at SAE not scientists, learn the difference. They spend more time working on and with engines than you can imagine.