No Thermostat: Is it ok?

Yo guys, I'm about to remove my thermostat housing to fix a leak at the gasket. My car has been overheating and I think the thermostat is broken and also i need to replace this stock 12 year old radiator. So the question is, should i even put a thermostat back in it? I dont care so much about the heater, it wont be cold for quite some time and i'm real warm natured.

So, can i run the car without the thermostat? THANKS!
-E
 
Yeah, if you don't your car will be running below the right temps I would think... or it would flucuate alot... the thermo is meant to stay closed until your car reaches a certain temp then it lets the coolant flow thru the motor... depending on your setup anywhere from 170-200 is optimal operating temp
 
Grandmaster said:
Yo guys, I'm about to remove my thermostat housing to fix a leak at the gasket. My car has been overheating and I think the thermostat is broken and also i need to replace this stock 12 year old radiator. So the question is, should i even put a thermostat back in it? I dont care so much about the heater, it wont be cold for quite some time and i'm real warm natured.

So, can i run the car without the thermostat? THANKS!
-E

NO! Your car needs to run at a certain temperature, w/o a t-stat you will run rich and have overall bad drivability. Get a Mr. Gasket 180* t-stat and be done with it.
 
I would think that without a thermostat, the motor would eventually overheat.

Why?

In my opinion without a stat, there would be nothing to regulate the coolant. In other words, the coolant would not be in the radiator long enough for it to cool.

I may be wrong.
 
5.02GO said:
I would think that without a thermostat, the motor would eventually overheat.

Why?

In my opinion without a stat, there would be nothing to regulate the coolant. In other words, the coolant would not be in the radiator long enough for it to cool.

I may be wrong.
The thermostat usually stays open once it initially opens throughout the duration of your drive.....so that wouldnt make any sense :shrug:
 
With no t stat your car will run cold all the time. this will cause issues with the PCM because it uses the ECT to determine when the car is at operating temp and when it need to be in closed loop mode. If you run the car with no t stat more than likely the PCM will keep the car in open loop and you will run rich because when you are in open loop the PCM isn't looking at the O2 sensors for any input to measure what the mixture is. It will always run rich since that is the default in open loop thus causing your fuel economy to suck.
 
Grandmaster said:
Thanks for the help, I'll do that. Where can i get a Mr. Gasket though? I've heard they are the best. Last time i bought a t-stat though I got some junk brand...ugh.

Can i find Mr. Gasket at most parts stores?

Go to any Autozone, O'Reilly's, Advanced Autoparts, etc. and ask for the Mr Gasket Balanced HP thermostat 180* part #4364 and they'll hook you up. It was about $8.00 last time I checked.
Tim
 
I have seen before and know for a fact, "(im a tech at toyota) that not running a thermostat will not only cause drivability issues, but can cause cold spots in the engine and that can lead to oil sludge. we have been having this issue with failing thermostats in the toyota sienna where the t stat fails open and the motor becomes a "sludge motor". this is warrantied by toyota fortunatley. just a precaution!
 
I had a Jeep Cherokee sport with no thermostat a few years back, and it would take an hour or more to warm up, but if it got warm finally, and then I got stuck in traffic, it would overheat.
 
I'm surprised with 11 replies NO ONE has actually answered as to why running no T-Stat is BAD! The reason remains that the thermostat not only regulates the temperature of the coolant, but also keeps coolant PRESSURE in the motor! Without a restrictor (a small opening), coolant will not be able to reach the higher coolant passages in the heads causing the coolant to flow slowly and weep throughout the motor without cooling critical areas. All this non-sense means hot spots, randomly throughout the motor, which can lean to detonation on certain cylinders.

YES, you can GUT a thermostat (cutting out everything except leaving the hole) and still maintain optimum pressure or even run a 160 thermostat.

I'm currently running a 160 thermostat with 4 drilled holes around the outside and it works GREAT in the summer (highest it ever got was 180) on a stock cooling system. I went from a 195-180-160-160 w/ holes and the only difference I noticed was a COOLER water temp! I also run a GUTTED thermostat on my 85' and the motor cools A LOT better than when I tried the 160-180-195...Despite a lot of people saying running cooler than 160 degree's is bad for your motor and what not, I've never had a problem. Go with a 160 or 180 thermostat!!

BTW- All my info has come from many cooling experts including Stewart Water Pumps and Griffin Radiators and my EXPERIENCE! I hope I helped
 
sgarlic said:
I had a Jeep Cherokee sport with no thermostat a few years back, and it would take an hour or more to warm up, but if it got warm finally, and then I got stuck in traffic, it would overheat.

A good example of having no pressure in the system caused by no restrictor. You're better off running a thermostat than no thermostat or at least gut the stat.
 
I`m pretty sure I recall reading in a high school auto shop text book years ago that an engine run without a thermostat would experience much faster cylinder bore and piston ring wear,as well as being less efficient and more likely to suffer sludge build up.

There`s no way I would ever run a car engine without a thermostat.

My 89 has a Hi-Flow 195* thermostat and three core rad,factory fan.Not even a hint of overheating with AC on the hottest day`s.