Over Cooling

[choppedtop]

OK, Lucy, splain this. (in my Ricky Ricardo voice) I was concerned that my 350 sbc was over heating. 190 thermostat. At long traffic lights it would get up to 22o degrees. I decided to run with out a stat thru the summer. It would run about 150 degrees on the highway at 2000 rpm, in 90 degree weather. When the weather changed to winter, I put in a 160 thermo. It never would get above 150 degrees at 2000 rpm. At traffic lights, up to around 180/185. Within about a block, back to 150.
I boiled the thermo a while ago. It starts to open at 150, and is fully open at 160. It doesn't close fully until 143 degrees. Does that sound normal? I am going back in with a 180 thermo to see what happens.
I figure with the knowledge here, I will get and good answer. BTW, I have a temp reader, and it reads within about 3 degrees of my temp gauge in the dash.
Thanks, Lee

 

[RPM]

You are lucky, most folks have trouble over heating. I would put the 195 thermostat in it and run it. You really don't want it running cold like that.

 

[PotvinGuy]

Nothing wrong with 220. I run that year round. Do you ever boil over? What's the pressure rating of radiator cap? Do you run an overflow tank? Does the radiator stay full? Do you run an electric fan? And let us know how the 180 stat works out.

 

[RPM]

Nothing wrong with 220. I run that year round. Do you ever boil over? What's the pressure rating of radiator cap? Do you run an overflow tank? Does the radiator stay full? Do you run an electric fan? And let us know how the 180 stat works out.

Yes 220 is fine. Most all the production cars the electric fans don't come on till they reach 220-230.

 

[choppedtop]

Cap pressure is 13#. I do run overflow tank. Engine driven fan. No water loss from radiator.
I did a 12 mile test run with the 180 stat. At road speed it runs 165. Sitting for about 5 minutes, up to 190. I don't understand why it runs cooler than the thermostat. I doubt if the gauge and the electronic heat tester could both be off about the same amount. I may try a manuel gauge just to satisfy my curiosity. The engine did run better at that temp, and did not bog down under full throttle as before.
Lee

 

[railroad]

Sounds like you have a good cooling system, but it does not pull quite enough air at idle. 220 would make me a little nervous, too. I like a little cushion for the those extremely hot days or situations. With a manual fan, the solution may be as simple as a shroud, which can be no more than a band of alum around the fan diameter. If there are gaps around the outer edge of the rad, you might seal them off. Look under the hood of all new vehicles. They have flexible filler from the rad edge to the fenders or core supports. Something simple like this can improve the efficiency of your fan. I know you knew this was coming, but an electric will move more air than an idling engine fan. My favorite protection is a bottle of Red Line water wetter.
Good Luck,

 

[choppedtop]

It is not really the 22o that bothers me so much now that I have read, heard, and been told that is pretty much normal for a high temp. It is the running cooler than the thermostat is suppose to maintain. I guess I will give it a try this weekend on my trip to Oklahoma city, which is about 100 miles and will be in quite a bit of stop and go traffic once we get there.
Thanks for the advice and suggestions, Lee

 

[TriodeLuvr]

Mine gets hotter by at least 20 degrees running down the road at 60 mph than it does idling at a light.

Jack

 

[T-Test]

Do you have a stock water pump or a high flow pump? A high flow pump is not needed on most cars and can sometimes cause what you are describing. Engine temp is critical to performance and should remain steady and higher than 195* for best performance.

Nascar cars run anywhere from 240* to 280* before spitting out water, and they don't blow head gaskets very often or warp the heads, crack the blocks.

 

[choppedtop]

Stock water pump. At least I assume it is. Came from Speedway, and didn't order anything special.
Lee

 

[T-Test]

Some of Speedway's pumps come with an impeller kit installed for higher flow. Nothing but a sheet metal plate riveted to the impeller blades to force the water in one direction. Check your sales receipt for pump number and look in catalog to assure you are right. I really don't see anything wrong with your cooling system as it is now.

 

[choppedtop]

T-Test, the problem that I am having is I can't keep the temps up for highway driving, which in turn doesn't burn the gas cleanly, not to mention poor performance.
Now, if I had a high volume water pump, how could that affect the engine temp, with the thermostat closed? Wouldn't that just be moving water about in the engine, and not really cooling anything? Not being a smart arse, trying to learn something here. I am just baffled by the engine staying colder than the thermostat temp. If I sit and idle, the temp will rise to 180/190. Hit the highway and in a mile or so, its back down to 160. And If I have a 180 stat, how can the water temp be lower? I know the gauge can be off, but doubt if 2 of them are. BTW, I have tested the thermostats.
Lee

 

[T-Test]

Water bypasses the T-Stat until it opens, if not the pressure would blow the radiator or hoses. Too much water flow through the radiator with the amount of cooling air while driving causes the T-Stat to close over and over again so engine can't reach a set temperature.

Intake gaskets some times have restrictor plates for the water passage ends in the intake. Small metal plates that lay on intake gaskets at each end. Does yours? If not, the water is not being restricted enough to heat up to temperature and stay there. There is such a thing as too much flow. Or you could have a reverse flow pump and not realize it, which it should then be running hot all the time.

Everyone wishes they had this problem, but it is a problem that needs correcting or you will never see any great performance from your engine without the heat.

I'm almost out of Ideas/Remedies unless you tell me more or I could see things in person. Hope this helps or carry your car to a radiator shop and let them look at what you have and explain things to them.

 

[2old2fast]

Chopped , mine acts much the same as yours , never more than 165-170 on the road w/ a 180 stat . At idle it will climb to 210 , where the fan kicks in & drops to 190 , I've tried different stats, no difference, I chalk it up to a good cooling system & an open engine compartment ???
dave

 

[choppedtop]

Thanks Dave, that is at least some encouragement that I am not the only one with that problem. Maybe it is not a problem, just the way it is. As long as the engine is happy, and not overheating, I will stop messing with it. Ya, my engine is open on the sides with just a louvered hood top.
Lee

 

[old round fart]

I had a friend that had a bra made for his '50 Ford panel truck with screen wire over the hole in the front and it overheated. How about some screen wire in front of the radiator to slow down the air? If it looks bad it may work on the back of the rad as well. John

 

[choppedtop]

Hey John, how ya been? Maybe I need louvers that open and close like a diesel truck. I have thought about a screen behind the grill to keep the wildlife off the radiator.
Lee

 

[2old2fast]

While a screen might work at road speed , it could impede air flow at idle .... not good.
dave

 

[railroad]

Check your timing and a/f. If they are off, it might affect your cruise temp.

 

[old round fart]

Hi Lee, just easing along. Working on the '50 a little, but can't shake the love for these little cars!