Running without a thermostat ok?

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Did you try testing the thermostat? Maybe it's not functioning properly? A simple thermometer and a pan of water on the stove will tell you when, or if, the thermostat is opening and at what temp!!
Yes. I always test a thermostat in hot water before installation. Didn't have a thermometer but it opened up shortly before the water started boiling so I felt good about it being 180*. Thanks!
 
Your engine isn't overheating until it boils over. 220° isn't overheating just because water boils at 212° in a pan on the stove. Every pound of pressure from your 15# cap adds 3° so instead of your coolant boiling at 212° it doesn't boil until around 257°. Using a 50/50 mix of coolant adds a few degrees to the mix also. Hot ambient temps, extended idling, and working an engine can cause the temp gauge to rise but until it boils inside the engine and boils over it's not overheating.
 
I had cooling problems, I added a secondary 16" 2500 cfm push fan from summit racing ($150) and i put it on a toggle, I only use it in traffic or really hot days. Did the trick like magic! I agree with everyone else, not enough air flowing through the radiator was more my problem vs a thermostat issue.
 
Your engine isn't overheating until it boils over. 220° isn't overheating just because water boils at 212° in a pan on the stove. Every pound of pressure from your 15# cap adds 3° so instead of your coolant boiling at 212° it doesn't boil until around 257°. Using a 50/50 mix of coolant adds a few degrees to the mix also. Hot ambient temps, extended idling, and working an engine can cause the temp gauge to rise but until it boils inside the engine and boils over it's not overheating.
That's good news. I am running fresh 50/50 coolant. Thanks!
 
I wasn't sayin you were stupid friend. We all take stupid pills from time to time. I was simply trying to point out that we were really not discussing electric water pumps in this discussion.....at least I was not. Those are not street friendly for the most part. Yeah, I know. You run one or know somebody, blah blah blah. There will always be the exception. I meant no offense.

First off I run with a T-stat, a stock mechanical pump in a cast iron housing. The stat I run is a 160 high flow. Car runs anywhere from 180-205 depending on the circumstances. 100 degrees out idling, I don't have a problem.

My reason for mentioning the CSR electric pump (with is rated and recommended for street use) is that they are not recommended to be run with a T-stat. I will say I ran mine with a 180 stat until I found this out when talking to a rep. Then I went with the largest of the restriction rings they sell.

If you read further down there is another member running a electric pump on the street. He runs 190 degrees with no restriction ring.

I know the OP doesn't have an electric pump. The reality of it is you should run a T-stat for reasons OTHER THAN overheating or cooling. Quickened warmup times and a temp healthy for the engine to operate in is what I mean by this.

On the flipside guy saying they run a 195 stat and never see over 180 on their gauge opens up a whole other can of worms.
 
I drove the car on Saturday and saw the highest temps yet. I have been able to keep it at 190 with the fan on but not that day. Was nearly 100 degrees out, had about a 30 mph tail wind driving home 45-55 mph (2000-3000 rpm). She hit 220 and I pulled it over. Sat for 3 or 4 minutes with the water pump and fan going, got the temp to 180 and drove on again. Got to 220 again by the time I got home. I don't know if it would have gone any higher than 220, but I didn't want to let it. I imagine if I were driving into the wind it would have helped since it seems there is also an air flow issue I dealing with. But I defintely think an air dam plus some working on a restrictor plate would fix any further temp issues. I also can still switch the fan over to the high setting. Right now just using the low setting.
 
As a stop gap and also a bit of a test...... Do you have the heater in the car? Just turn that on with the blower on high and it ought to take a fair amount of heat out of the engine. Of course, open the vent doors for yourself!

And perhaps this is a subject for a separate thread in the heating and cooling subforum......But, would you mind posting a pix of, or describing your fan mounting? There looks to be a rash of electric fans being mounted on flat, solid plates that block all the air through the rad except for a single large hole through which the fan pulls air. These are a good recipe for poor heat extraction at highway speeds.
 
Just for the heck of it drive it with the vacuum advance unplugged if it isn't already.... My 76 Duster with a slant was getting hot on the highway and I discovered that the total timing was 65 degrees with the vacuum advance. I backed out the adjuster and got it down to 45 and no more heat issue.
 
Your engine isn't overheating until it boils over. 220° isn't overheating just because water boils at 212° in a pan on the stove.

Yes, but boiling the thermostat on the stove can verify that it is opening. I check all of mine that way.
 
No heater, no vacuum advance either. It's mechanical. The fan shroud covers 75% of the radiator. I'm not really looking at trying to solve the issue here. Was just throwing out my experience thus far. I'm sure I'll get it worked out eventually.
 
Can someone explain why some people say an engine without a thermostat will overheat? I don't entirely believe that because an engine with a thermostat stuck open runs cold from my experience. I read the information in the link above, interesting read.

Because they can and do. Not trying to be a jerk. There are several examples in this thread some based on theory, some on experience, and some a little of both along with logic. Time in the radiator has some effect in allowing the water to dissipate heat though not as much apparently as pressure and restriction keeping the heads full of coolant and not steam pockets.
 
Time in the radiator has some effect in allowing the water to dissipate heat though not as much apparently as pressure and restriction keeping the heads full of coolant and not steam pockets.

Exactly, yes.

Can someone explain why some people say an engine without a thermostat will overheat? I don't entirely believe that because an engine with a thermostat stuck open runs cold from my experience. I read the information in the link above, interesting read.

Not all will overheat with no thermostat, but some can. There's many variables, but an engine which runs very hot or even overheats WITH a thermostat might run even hotter without one. It's simply because the cooling system is rather marginal in most of these cases and removing the thermostat is 'the final straw' and local pressure in the block drops just enough more to allow steam and it snowballs from there.

An engine that already runs cool enough won't overheat if the thermostat is removed, it'll probably run stone cold all the time or barely get warm.
 
I think worrying about a car running at 220 is sort of panicking. I drove mine up out of the river valley yesterday it got to about 230 so I dropped a gear, the pump and fan spun a little faster and it cooled to 225 right away. The coolant in my car right now is at 105 and I haven't even started it yet.
 
I think this will be my new end all be all policy next time anyone chooses to tell me how stu-stu-stupid I am.

Glad your "truck" runs fine.

My **** works, my **** wins.

I also must say how some seem to be able to say the same things as others or disagree and yet not receive the wrath.

I 1000% agree with you on this,,,, seems to be those that are praised for snide or snarky comments on this forum, and others that get ***** slapped for snide or snarky comments....and then they get praised for the ***** slapping, cliques that all it is. i dont care what forum or topic of the forum it is always like that.
 
I didn't want to read 4 pages of conflict so In my experience I have replaced many engines because of overheating. because someone removed the thermostat and at about 2000rpms the lower radiator hose sucks shut cutting of all water flow, most replacement hoses forget the wire insert .. just by 2 cents, hope it helps.
 
I didn't want to read 4 pages of conflict so In my experience I have replaced many engines because of overheating. because someone removed the thermostat and at about 2000rpms the lower radiator hose sucks shut cutting of all water flow, most replacement hoses forget the wire insert .. just by 2 cents, hope it helps.

Very good point! I have crammed old valve springs in a lower hose before to stop that and it didn't occur to me in this post.
 
I haven't been able to find a replacement hose with a spring in it.
Maybe they are out there.

p.s I hope my "general" rule was not interpreted to be an end all.
It isn't. It's just a starting point.
Has anyone mentioned "wetting agents" yet?
HA.
 
I didn't want to read 4 pages of conflict so In my experience I have replaced many engines because of overheating. because someone removed the thermostat and at about 2000rpms the lower radiator hose sucks shut cutting of all water flow, most replacement hoses forget the wire insert .. just by 2 cents, hope it helps.

Please enlighten me on why the lower hose needs the spring? is it a mopar thing? is it needed when there is no t-stat? I find the spring hoses unpleasing to the eye, buttt... if there is a need in certain situations id like to know....thanks.
 
Please enlighten me on why the lower hose needs the spring? is it a mopar thing? is it needed when there is no t-stat? I find the spring hoses unpleasing to the eye, buttt... if there is a need in certain situations id like to know....thanks.

Two reasons:
When running, the water pump can suck hard enough to collapse the lower hose at higher revs. Seems to be combo dependent (radiator, pump, thermostat, cooling passage mods, etc).

When not running, as the engine cools will go from pressurized to negative pressure (Vacuum) which is supposed to draw the coolant back from the recovery tank. Sometimes the lower hose can collapse and prevent it from drawing from recovery, and once restarted can cause flow issues and may remain collapsed due to the pump 'sucking' on the hose.

The bendy/flexy "spring hoses" aren't necessary, you can put a spring into a standard hose to give it some support.
 
Please enlighten me on why the lower hose needs the spring? is it a mopar thing? is it needed when there is no t-stat? I find the spring hoses unpleasing to the eye, buttt... if there is a need in certain situations id like to know....thanks.
Not just a Mopar thing; I've found/seen them in other cars/trucks. It's a very loose spiral wire that conforms to the inside of a standard hose, about 1 turn per inch. not the flexy hose you may be thinking of.
 
Please enlighten me on why the lower hose needs the spring? is it a mopar thing? is it needed when there is no t-stat? I find the spring hoses unpleasing to the eye, buttt... if there is a need in certain situations id like to know....thanks.

A hose with a spring in it looks exactly like a hose without a spring in it.
 
Not long ago on another forum a similar topic came up and a curious thing that's obvious now that it's been exposed turned up. What should the pressure in the block be? In that forum's brand Ron Davis likes to see about 14 psi above the cap's pressure rating. this is measured right at the backside of the t-stat. Think about what the does for the boiling temperature of the coolant in the block! In an engine on the edge, be it a high state of tune or one with mechanical issues, losing the t-stat means that it looses a significant amount of boiling protection, and now it will over-heat.

Something else that hasn't been touched on is the rate of thermal transfer as related to the differential temperature. "The more radical the difference, the more radical the reaction" was what I was taught in A/C-Refrigeration class. This was demonstrated with two styrofoam cups of R-12 (instructor would likely be hanged in this state these days for doing that). He poured cold tap water into the first cup. Made the most bitchin looking ice sculpture. Then he poured nearly boiling water into the second cup. It blew up. Barely found pieces of the cup.
Now I know that's different fluids, different materials, etc., etc., etc. However, the premise is the same. I've seen this show up in engines. Those with a 'cold' t-stat tend to fluctuate in temperature much more than those with a 'hot' t-stat. I'm not saying that all behave this way, only that most do. There's almost always an exception and an exception doesn't disprove an observation.
My understanding of what is happening is that the higher temperature water actually dumps more BTU's into the ambient air than does the relatively colder water due to it's greater temperature difference. So the cold system cycles hot and cold, but the hot system maintains a more consistent temperature. Sometimes that cold system cycling is pretty slow, other times it's not very slow at all.

Some years ago the race prep shop that I was working for had an engine freshened up by an engine shop whose main claim to fame was their IRL racing series engines. Our engine came back with very specific instructions on how to make it's coolant restrictor and the required swirl pot for removing cavitation bubbles from the coolant. A flat plate with a hole in it was not only unacceptable, it would've voided the shop's willingness to stand behind their work. The restriction needed to be a venturi in shape and the exit coolant from the engine had to go thru it and then enter the swirl pot tangentially. The pot had to be placed so that the cap on it was the highest point in the system. Additionally any local high spots had to have bleed tubes run to the pot. That engine held temperature whether it was being flogged on or was driven slowly under a yellow.
Since then I've not had much patience for the disc restrictors that Moroso et. al. sell.
 
When I worked at the local Citgo station in the mid 70s, every single bottom hose we had came with the spring. The bottom hose is the suction side. As engine RPM increases, so does suction. In a closed system, the suction has no relief, so if there is no spring to support the bottom hose, it will collapse at highway speed and restrict the inlet flow to the engine from the radiator.

I know. Next you'll say something really stupid like "why don't hoses come with springs now? Don't be stupid. How much would springs cost? How many millions of hoses do you think hose manufacturers make every year? Yeah. Somebody saw where they could cut a corner and did it, just like everything else.

Some of yall need to stop being so damned hard headed and LISTEN to experience, instead of being borderline stupid.

If that does not explain why you need the spring in the bottom hose, then turn your keys in and take up stamp collecting.

That might be too difficult for some of you so might I suggest drooling instead?
 
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