I know no one asked or probably cares but I thought I would throw this out there. My radiator began to leak this winter, so I did what anyone would do and got a new one, at the local advance (why I don't know but it payed off this time) upon getting it home and ready to install first thing I notice this thing is a whole lot larger than the original. First thought, get pissed, second thought, see if it fits. Well it bolted right in to the radiator support and the hoses lined up but the fan shroud wouldn't fit. So I gave them a call they said it was the right one, I said it wasn't so they asked for the part number then he gets back on the phone and states that it is a heavy duty unit so I can bring it back and they will replace it, I asked the price of the original and they state the price I paid they said the one I had was more expensive only by 20 or so dollars but still. I get off the phone and thought quickly I just saved 20 or so and got a hd radiator. Only drawback is you have to drill new holes for the top of the radiator support into the radiator (there is a little tab that the shroud attaches, you'll know what I am talking about) to affix it to the radiator and you have to secure the bottom with a home made piece although I didn't and it doesn't flop around so I left it alone. The new radiator comes with new fittings/ adapters to secure the trans fluid line to the radiator you have to take them out and reuse your old ones no big deal. With a 150 degree thermostat my truck gets to 160 on a very hot day during the winter or below 80 or so it drops or opens at around 150 doesn't get warmer, reason I have the 150 thermostat is because they did not have the 170 again it paid off I guess. So if you ever wondered if the heavy duty radiator would work/fit I will tell you it does if you wanted to make it look stock go to a junk yard and get a fan shroud off a heavy duty truck (utility truck, possibly the f-250/350). So if your gonna get a new radiator anyway why not spend a little extra and get something a little better. The trans cooler is bigger so I would say that helps the tranny dramatically as well. Long answer to a question never asked

 

Why would you want your truck engine to run less than 180F???

At 170F your engine is wearing 2 miles for every mile you drive.

At 160F your engine is wearing 4 miles for every mile you drive.

At 150F your engine is wearing 8 miles for every mile you drive.

 

I was going by this thinking. A warm motor burns emmisons off a little better but then again I have no cats and an aftermarket carb which is no way tuned to its peak, so from my perspective there it doesn't matter much. On the other side as the engine warms everything expands and if the engine runs a little cooler things expand less, I would think that means less wear, not saying I am right in any way as I would like you to elaborate. Not trying to be a smart ***, I would genuinely like to know. Thank you for your time

 

Good old SAE engine tests... It is a chemical reaction that occurs on the combustion chamber walls that spreads grit thru the engine.

Your engine efficiency goes up with temperature also.

Brake fuel consumption goes up with lower temps.

Lowering your engine temp does EVERYTHING wrong. Why do you think the automakers keep increasing thermostat temps?

Put in at least a 180 thermostat or the temp specified for your engine and year.

 

I looked around and come up with some more indepth reasoning to your post and I get what you were saying. However there were some debate over the temperature. The temp debate fell into the efi catagory of weather or not the motor would reach closed loop state makes since from that perspective, still believe there may be a performance advantage to a lower thermostat in a race situation but from my stock stand point not much to gain. Live and learn, appreciate it

 

You can pretty much discard the open loop/ closed loop EFI debate as far as engine wear is concerned. That is just programming for the computer.

You can go to a big technical library and read about the SAE engine test procedures and results.

You may get an initial performance increase the first time you hammer down from a cooler engine, unfortunately in a race or in extended performance situations your engine temp will climb to higher levels that depend on many factors.

Some of the modern engines with computer designed cooling flow paths and cooling systems work a lot better than the older motors do. The engineers always like to keep things controlled in an engine and the ability to keep the temperatures within tighter limits has made better efficiency possible. The modern engines are better in this respect.

Cooling flow is one of the reasons that during a rebuild you pay particular attention to the cooling passages in the engine and head. I have seen a lot of engines that had tons of gunk in the cooling system passages and were just assembled with same...

 

You will love this, today I noticed the truck runs between 145 and 150 it's about 80 and humid outside. So the thermostat must be a 150 I couldn't remember which on I used. I would just hate to mess up a good thing as this thing runs really well for a stock truck not to say it is due to the temperature. I am planning on changing the thermostat in the near future just to make sure no acid forms in the oil from the lack of heat/ chemical reaction from moisture etc., I would just hate to mess with it cause I have spent some time adjusting the fuel timing etc to get it to run and me be happy everytime I run it. Oh well maybe it'll pay off in the long run. Later

 

Hi, I run a 160* thermostat in my 1990 Bronco (5.8L). I don't know where you guys got the idea that a warm running engine is good. Actually a cool engine is a happy engine. Also you will not have to worry about moisture in your oil. You said your truck runs at 150*. That is not the actual engine temp that is the coolant temp. If you don't believe me next time you change your oil, do it when the engine is fully warmed up. THen after you drain the oil stick one of those cheap cooking thermometers in the oil. It should be over 200* As we all know water boils at 212*F.

So bottom line is you made a great decision. This decision will definelty make your engine last longer.

P.S. I even run my truck with NO thermostat in the hot summer months. The truck takes 1 hour to get warm. It never moves past the first line on the gauge!!!

 

bronco351-

RUNNING WITHOUT A THERMOSTAT IS THE ABSOLUTELY WORST THING YOU CAN DO TO AN ENGINE short of not changing the oil! VERY VERY BAD!!!

Where did you ever get the idea that running an engine cold is GOOD for it???

Check out the SAE tests yourself at the local library if you want to read some actual test data. But for heavens sake back up your information with some facts man! Get to the library and read some solid engineering info.

While the cooler temps will form more acids in the oil due to combustion byproducts (has nothing to do with liquid water) the increased wear mainly comes from a chemical reaction during combustion near the cylinder wall that eats up the iron in the cylinder. This reaction releases wear particles into the oil that tear at the entire engine! The number of particles released are too great for the filter to pick up and keep circulating causing even greater damage to the rest of the engine.

Without a thermostat your fuel economy will be horrible.

I see your engine is currently under construction, what happened, did the old one wear out???

 

bronco351 maybe you could explain yourself a little more, hey I thought cooler was better until torque1st made some good points. Keep up the discussion it's getting interesting.

torque1st what does temperature have to do with the chemical reaction? Does it only occur below a certain temperature as that is what your getting at, what temperature would that be? What is this reaction caused from, you state it occurs but what is happening to cuase this? Later

 

I biggest reason for running an engine at proper temps is for expansion of the internals, such as the pistons. Pistons are not round they are oval shaped. They are made this way due to the different densitys from the skirt to the crown and etc. Different densitys will expand at different rates depending on the heat they are in. Too cold an engine causes piston slap on the walls and various other wear. I like to use a 180 tstat in my 63, not too hot but not too cold either. Regardless of what you use now you shouls use atleast a 160 tstat if not a 180. I use a 192 in my f150.

 

The chemical reaction occurs at temperatures below 180F water jacket temp. It is a reaction that forms chemicals (acids) that etch the cylinder walls. Above 180F the combustion process reaches the cylinder walls and reduces the fuel to normal combustion products so the acids do not form. Because of the granular construction of cast iron the acids eat at the material in between the metal grains faster than the base metal. The granules of metal come loose and act just like microscopic metal "grit" inside the engine. The grit of course scrapes away at the cylinder wall itself and rips off more grit. The grit gets into the oil and grinds into the rest of the bearings, lifter bores, lifters, cam, and valvetrain. When these components are ground and blasted by the grit they produce more grit particles... The filter only removes a certain % of the larger particles with every pass of the oil thru the engine. With large numbers of particles being produced the filter's capacity to remove the grit is compromised and rapid wear is produced.

The organic acids produced also collect in the oil and erode all of the metal surfaces in the engine. Liquid water is not required for this reaction, just a few water molecules, which are everywhere, is enough. Burning fuel produces water vapor (water molecules).

Lower temperatures also produce more fuel "washdown" effects that remove lubricating oil molecules from surfaces.

Cold pistons do produce more impact wear (piston slap) on the cylinder walls and skirts. This can also lead to fractures in the piston skirt.

I have explained all of these reactions many times b4, but people will not read and do their homework.

I guess what I should do is combine all of this into one "explanation" and store it in a text file that I can just copy and past into a post every week or two.

 

If the topic comes up enough you should copy it.

 

The reason my engine is currently under construction is not because the old one wore out. I'm building a 480 h.p. engine to replace the stock one. I need more power!!

As for the running with no thermostat is bad for the engine. I would have to dis-agree. I once had a 1987 Ford F-150. I ran that truck with no thermostat for it's entire life. It ran great till 250,000 miles then I sold it. Running cars/trucks is just something I have always done to most all my cars. I live in Arizona where it gets to be 115*. Almost everyone I know that works on cars in AZ also suggests that you either put a 160* thermostat or take it out completely.

 

Just because a lot of people do something does not make it right. It is still a very bad idea to run without a thermostat. Ambient air temps, cooling system design and condition determine the engine temp under load. Running with anything less than 180 is just "fuelish". Believe me if the thermostat was not required in an engine Ford would save the cost and leave it out!

Why don't you find a Ford cooling system Engineer to talk to? Ask the Engineer, not a mechanic or salesman, if it will void your warranty on a new engine to run without a thermostat.

I am an Engineer and all I can do is try to educate people. If people don't want to listen that is their problem.

My sig says it best: "You can lead a horse to water, -but you can't make it drink..."