Operating Temp???

[55 Fargo]

Hi all, took my car for a spin yesterday about 5 miles, the ambient temp was 0, my garage was about 30, where the car is parked.

After a quick warm-up, I went for a spin. I have 160 t/stat, it also has a tiny hole drilled in it to let water circulate a bit, I have an internal type system and t/stat to match. I drilled the hole to allow air to escape when refilling the cooling system last.

Anyway, the temp gauge was bang on 160 when warm, the rad temp was about 145 to 150, this is an aftermarket cheap gauge I have, and I do know it's out, at least 10 degrees.

At this temp, and mind you it was a short ride, the heater does not get overly hot, which is fine, the car is not supposed to be driven at 0 farenheit.

I have recently changed the timing on my engine, I discoverd the points were only gapped at .010, I have changed it to .020, this change would change the timing wouldn't it, hopefully she runs between 165 and 190 during the warm summer weather......................Fred

[Niel Hoback]

I have a 160 stat in mine and I have never seen it go over 165 at any time. I think if your cooling system is working properly , the temp shouldn't go over the rated temp of the thermostat.

[Young Ed]

I've seen mine go over the 160 when its quite warm and I'm out on the freeway or stuck in traffic. I wonder if some of the freeway issue isn't because I don't have the bumper splash pan or under grill sheet metal in place though.

[55 Fargo]

According to my Chrsyler shop manual, the 160 degree t/stat should open at 147 to 153 and be fully open at 180.

165 degrees is a little cool to run an engine I have read in our tech section under Greybeards threads, the engine will run cleaner and more efficient at 180 or so.

Greybeards quote from "Thoughts On Mopar Flatheads part 2"',

How does this all relate to MoPar flatheads? The design of these engines is such that a water distribution tube is used in the cooling system to aid in dispersing coolant to the bottom of the exhaust valve seat castings. In this sense, these engines are truly overbuilt, for this is a feature not used by very many other manufacturers of the time. An analogy to this feature would be oil nozzles directed to piston crowns in modern diesel engines – a feature that goes far to extend engine life. Flathead radiators are also overbuilt from a size standpoint, and are truly impressive in their ability to transfer heat from the engine and transfer it to the air. When these engines are warmed up to 180 – 200 degrees F, they run happily all day, run more efficiently and stay cleaner. They live linger, as well.

Once it is warmed up and opened, it does not keep the coolant temp at 165, once opened fully it can rise higher, especially on very hot days and driving slow or stop and go.

[BobT-47P15]

Seems as if mine runs around 180 regularly. Water in top tank of radiator

is always just a little low.....because the car spits it out till reaching it's

desired level. I had an aftermarket under-dash gauge for quite a while, but

now have an original n-o-s one in the proper place. They both have said

the same about the operating temp.

We have snow here today, so don't think I'll be doing any driving of the Plym

for a while yet.

[55 Fargo]

Snow, Bob, was it not in the 70s in Joplin the other day................Fred

[BobT-47P15]

Yes.....it was in the 70s Monday. Go figure.....

[brian hood]

I am not sure if this applies, but my old truck ran fine. However, it had water in the oil. When I took the head off, someone had removed the Tstat. I guess it had ran hot and that was their attempt to check it. Anyway, I do know that if your head is 10 thousandths off, it will run fine, but at a highr temp. Please, post your final results so that we can all learn for this.

Brian