The Stickman

I was putting new intake gaskets on to see if I could cure my massive vacuum leak. I got it all buttoned up when I saw the thermostat laying out. I just forgot to put it in. I would hate to have to drain the system again. SO can I run without it?

redoldsman

You might be able to but it is not advisable. It would depend on how hot is gets where you live. There was a time when we used to take our thermostats out in the summer. The thermostat actually slows the flow of coolant down going through the radiator so it has time to let the radiator do it's job. Otherwise it will move through the radiator too fast and will actually run hotter.

88 coupe

You can, if you want your engine to run cooler than it was designed to run.

Thermostat has one function: To maintain normal operating temperatures by restricting coolant flow.

Another myth.

The theory is: Water flows through the radiator so fast that its heat cannot be transfered. If so, why doesn't it flow through the engine so fast that it cannot absorb any heat?

Norm

jensenracing77

i have seen both of the above happen in differant situations. i have seen people take the water pump and grind vanes off to slow down the water. you should run with the thermostat to avoid either one from happening. more ofter than not you will run colder without a thermostat.

Redog

Yeah I would just suck it up and drain SOME coolant and reinstall the thermo

88 coupe

Excellent way to create cavitation, which would cause overheating.

Norm

jensenracing77

i know that i would not do this but i seen it done. ( the water pump thing) i like to keep things more like they were ment to be.

88 coupe

I have seen a lot of stupid things done, during my short lifetime. Need I say any more?

Norm

SIPLOWGUY

It's best for the engine to always run at operating temperature. You need the thermostat to insure that.

Texascarnut

Running an engine without a thermostat is basically a very bad idea. It may actually lead to the engine overheating as the presence of the thermostat allows the radiator to do what it is suppose to do, reduce the temperature of the coolant. Without a thermostat coolant is circulating through the radiator at a flow rate too great to maintain the coolant temperature at less than 190 degrees. An engine without thermostat or a thermostat that is hung open will get hot enough in summer months to basically boil all the coolant right out, and in pretty short order.

380 Racer

I run a restrictor with a 3/4" hole in my drag car. It stays cooler than no thermostat. This is a proven fact.

Warhead

And do not use a "HP" unit. If it opens far enough, it gets jammed open.
Just as bad.
POS.
Jim

jensenracing77

Jo Mondello is the one that recommended it to someone in a seminar that i attended

Hydro462

The motor will not run as efficent as it will when hot..

I like the Stewart t-stats..
***Beware, Mr.Gasket sells a look alike but it is a POS***

http://www.stewartcomponents.com/tec...ech_Tips_3.htm

70Post

That's funny--they are the same thermostats and made by the same company.

Hydro462

I e-mailed Stuart Components with this post.. I'll post the response......

70Post

These thermostats are manufactured by RobertShaw Industries.

Hydro462

The difference between our thermostat and the Mr. Gasket unit is that we
use a Robertshaw Thermostat from Cooper Standard.

The Robertshaw Thermostat is made for the racing application, it is made
with a larger mouth and is less restrictive when open. When open the
flow is more balanced.

The Mr. Gasket unit is a little better than the OEM unit but it is not
as good as the Robertshaw.

Hydro462

I know of about 15 failures of the Mr Gasket unit. People think they are getting the same thing at the Stuart only cheaper.... That was the same mistake I made.. Once I installed the Stewart unit all my t-stat troubles went away....

The Mr gasket unit I had worked on the first use then my temperatures began to creep up higher and higher with every use. By the fifth run my motor was over heating and the t-stat wouldn't open...

Seems like everything I buy with the Mr Gasket label ends up in the garbage can... I don't think it's the same company that was run by Hungarian Joe in Cleveland...

70Post

Good info Hydro!! Thanks for doing more digging on this. I'll stick with the stats from Stewart then...have a bunch of those and the Mr. Gasket stats will hit the recycle bin.

Thanks again.

spyke

So I understand some of this I have a 70 model cutlass and I have been running it without a T stat and my temp runs about 190* but after about 35-45 min. It climbs to about 200* maybe 210* if I'm in rush our traffic. I was told to put a 160* T stat in my car and drill some small holes in it , I had a clutch fan on it and it went bad so I bought a flex fan it didn't do the job now I have an electric fan with double fans and it still gets up to about 200* what should I do?

Erinyes

I'm not sure I would worry about it at all, if it's not actually overheating. Next steps, though, might be flushing the cooling system, checking the radiator for proper flow, and as a last resort a FlowKooler water pump.

oldcutlass

Spyke, there are numerous threads on this, 200 degrees in traffic is normal. Put a 180 degree superstat in there.

edzolz

Unless your temp gets above 230 or you lose all of the liquid, your engine is not running hot. Coolant under pressure will not boil at 212, like coolant that is not under pressure. The boiling point is much higher for an engine with a 15 lb pressure cap.

TripDeuces

I'm with 380 Racer on this. Buddies car kept overheating without a t-stat. In a pinch we took the guts out of an old t-stat and just used the center ring with the ~ 1 1/4 inch hole in it. Temp went right down and ran normal after that.
I'm not advocating running a restrictor plate but you should run a t-stat.

I've heard pros and cons about water moving too fast in the system to cool it and I'm still not sure what to believe. But I do know they work better with one or some kind of restriction. There's a reason car manufacturers use them. I'll trust their judgement for now and my own practical experience.

Cutting down the pump vanes would only seem to make the pump less efficient to me. Maybe it will free up horsepower but it's not helping pump flow. That's why they use electric pumps............there is no HP drag and you get the volume you need. The best of both worlds. I suspect Joe Mondello was thinking horsepower and not cooling.

ELY442

2x on 380 Racer. I, too, run on a smaller hole restrictor plate on my Post Coupe. They do sell the restrictor plates kits. Summit or Jegs sells them. I always have problems with any kind of thermostats on any kind of name brands. Maybe I bought defects.

I also agree with TripDeuces. I gutted out the thermostat on my Convertible and I never over heated on a NYC traffic. You cant run an engine "without" a thermostat. There's have to be some kind of a restriction to slow the water flow.

MDchanic

As OldCutlass pointed out, there are numerous threads on this subject, some of which I have posted in, so I will not belabor this, but slowing down the flow of coolant does NOT improve cooling, it makes it worse.

Installing a restriction in the outlet from the engine creates a pressure differential, with higher pressure in the engine and heads (as much as 40-50 psi), which keeps the water from microscopically boiling at the hot surfaces of the heads and improves heat transfer.

- Eric

rustyroger

Summed it up nicely Eric!.
Some of the old L head engines from years ago made do with no water pump and thermo-siphon coolant flow. That was ok in the days of loose tolerance machining and frequent breakdowns being the norm. Old pre war cars would often boil over going up long hills, you just pulled over until they cooled down and carried on.
But those cars didn't manage many miles until they were worn out, we have come a long way since then, modern technology has made cars more complex but they are light years ahead of old cars for reliability and lifespan.

Roger.

at3reg98

I say just put it in and get it over with. I know it's a pain in the *** to get to on the 307 but at least you won't be second guessing the temp for the next few months. If you kink the upper hose properly you won't lose much coolant and if you're patient and careful you can put the new therm in with a gasket without doing anything to the engine either. It'll make a mess but it's possible to do, even if it means jacking the car up to change the level of coolant in the area where it sits (so it doesn't overflow when you drop it in messing up the gasket area).

I had to replace a garbage Stant I had in my previous car after I finished work on it, it was new but the temp would climb to 250 or so and then suddenly drop as it opened. Delco and problem solved. I did it the way above too. Probably best to drain some coolant from the rad but my way did the trick.

jag1886

Put the stat back in, you only have to drain a gallon of coolant out should take a 1/2 hour at most to make it right.
You might get away without it in PA but you sure wouldn't in AR or ID.
Just put it back in and forget about it.

Redog

It's been a long time since he's been on here. He has a Olds 350 swapped in the wagon. I've seen it personally back in 2007