Thermostat removal

[theking11863]

Lately I've been looking into diverent things I can do to my engine to help prevent future head gasket problems. One of the ways suggested to me was to remove the thermostat completely from the engine so it runs colder. Now this sounds pretty sketchy to me, but I wanted to get some opinions on this.

I know on modern cars it can be very bad since they have computers that read engine temp and adjust other things like air/fuel ratios but since mine is so old I'm wondering also if that is not a problem for it with such a basic computer setup. Any ideas?

 

[Bad_Vision]

Your fuel consumption would be greater on the 22re as well.
It will cause long term problems like catalytic converter failure and carbon build up on valves as your mix will be constant rich.

Best thing to do is to get a oem thermostat with the weep hole and dongle in it.

 

[theking11863]

Your fuel consumption would be greater on the 22re as well.
It will cause long term problems like catalytic converter failure and carbon build up on valves as your mix will be constant rich.

Best thing to do is to get a oem thermostat with the weep hole and dongle in it.

I'll take that as a no go

 

[flyinhawaiian01]

I used to run no thermostat in my vehicles back in Hawaii (there's really very few days you actually need a heater in Honolulu!), but there's a trick to doing this properly.

You need to have some sort of resistance in the system or the water just runs through the radiator before it actually cools the system properly. You end up getting hot-cold-hot-cold pulsating water running through the engine which isn't very good for it.

Do actually run an engine without a thermostat, you want to cut the basket of the thermostat and reinstall just the washer part of the thermostat, like this:

The bottom brass part and spring will fall out, leaving you with just the top section. This will give enough backpressure for the system to regulate the flow of antifreeze through the radiator.

Be forewarned though, you will NOT have any heat in the vehicle! It will run extremely cool (less than 1/3rd of your heat gauge in the dash), and the vehicle will run slightly richer because of the cooler temp. Also, during really cold days, its possible to have your throttle body freeze up on you, as the system uses heated water to keep the throttle body from freezing up. In Hawaii, it never gets below 50º (at least where I lived it didn't), so it was never a problem, but where you live it could be an issue.

It won't hurt anything to try, except maybe your mpg's, and you can always throw one back in if you feel its not working for ya.

You could also order a lower temp thermostat, such as this one:

More Information for STANT 31066

That's a 160º thermostat for the truck (22re, not sure if its the same for the 3vze), pretty much wide open once the engine heats up.

 

[Bstrom]

From a thermodynamic standpoint, internal combustion engines require a minimum/maximum heat range to function properly, no matter where you live. As you have been advised, use an OEM thermostat to allow the engine to operate in its designed heat range. A number of expensive problems will ensue if you remove the thermostat completely or attempt to modify it.

If you don't want any internal cabin heating, you can bypass the heater core and prevent any coolant from affecting your cabin temps but upsetting the engine temperature is just plain foolish.

 

[theking11863]

I used to run no thermostat in my vehicles back in Hawaii (there's really very few days you actually need a heater in Honolulu!), but there's a trick to doing this properly.

You need to have some sort of resistance in the system or the water just runs through the radiator before it actually cools the system properly. You end up getting hot-cold-hot-cold pulsating water running through the engine which isn't very good for it.

Do actually run an engine without a thermostat, you want to cut the basket of the thermostat and reinstall just the washer part of the thermostat, like this:

The bottom brass part and spring will fall out, leaving you with just the top section. This will give enough backpressure for the system to regulate the flow of antifreeze through the radiator.

Be forewarned though, you will NOT have any heat in the vehicle! It will run extremely cool (less than 1/3rd of your heat gauge in the dash), and the vehicle will run slightly richer because of the cooler temp. Also, during really cold days, its possible to have your throttle body freeze up on you, as the system uses heated water to keep the throttle body from freezing up. In Hawaii, it never gets below 50º (at least where I lived it didn't), so it was never a problem, but where you live it could be an issue.

It won't hurt anything to try, except maybe your mpg's, and you can always throw one back in if you feel its not working for ya.

You could also order a lower temp thermostat, such as this one:

More Information for STANT 31066

That's a 160º thermostat for the truck (22re, not sure if its the same for the 3vze), pretty much wide open once the engine heats up.

Yeah that won't work for me... Even in Phoenix the temp drops below 50 in the winter, and I could be back in Big Bear and the snow then so that sounds like a bad idea. The sad thing is the guy who suggested this to me lives in Big Bear and knows exactly what conditions the 4Runner will go through.

From a thermodynamic standpoint, internal combustion engines require a minimum/maximum heat range to function properly, no matter where you live. As you have been advised, use an OEM thermostat to allow the engine to operate in its designed heat range. A number of expensive problems will ensue if you remove the thermostat completely or attempt to modify it.

If you don't want any internal cabin heating, you can bypass the heater core and prevent any coolant from affecting your cabin temps but upsetting the engine temperature is just plain foolish.

I'm not doing this to turn off internal heating. There are many switches for that lol. I was considering this to help prevent future head gasket problems, and I knew this didn't sound smart. I just wanted to double check that I was right about that

 

[VA_4R]

If you have multiple head gasket failures you need to have the block checked at the gasket surface.
My 88 4R 22re had 2 failures and it was caused by a water jacket in the block that had raised up, after decking the block, no more failures.
Replace antifreeze yearly and flush the system but don't use the flush products on the market use clean water only

 

[theking11863]

If you have multiple head gasket failures you need to have the block checked at the gasket surface.

My 88 4R 22re had 2 failures and it was caused by a water jacket in the block that had raised up, after decking the block, no more failures.

Replace antifreeze yearly and flush the system but don't use the flush products on the market use clean water only

I haven't had multiple head gaskets blow, (partly because I haven't fixed the first one lol) but I don't know the past history of the thing. I know its had the engine rebuilt or replaced before but I don't know why. I'm just trying to do as many preventative methods as possible to protect it. Since I'm bringing it to Phoenix its going to be under some really intense conditions, opposite of what its dealt with for at least the last 10 years. I'm just worried because its first trip into the desert and it already blew the gasket. Who knows what it'll do on off-road trips out here

 

[VA_4R]

I haven't had multiple head gaskets blow, (partly because I haven't fixed the first one lol) but I don't know the past history of the thing. I know its had the engine rebuilt or replaced before but I don't know why. I'm just trying to do as many preventative methods as possible to protect it. Since I'm bringing it to Phoenix its going to be under some really intense conditions, opposite of what its dealt with for at least the last 10 years. I'm just worried because its first trip into the desert and it already blew the gasket. Who knows what it'll do on off-road trips out here

Take your time with the repair
I know you dont want to hear this but pull both heads and replace as a pair or take both of yours and have them checked/ magna fluxed.
with a good straight edge check the deck of the block to make sure its flat.
to prep the surface I use a 2x3 steel channel with a belt sander belt cut and glued to the channel that is just as long as the deck surface and move it in figure 8's a little goes a long way so be careful. you dont want a smooth surface for the gasket a ruff surface holds the gasket when installed
Finally use good gaskets, I get mine from Napa.

About the thermostat these other guys are right, leave it in just buy a quality one, autozone and such have been known to have bad ones right out of the box

 

[DangerRanger]

I 3rd what the others have said about the thermostat.

I typically carry a spare just incase.. my current one is a cheap one with a hole drilled to keep air moving past it.

 

[BigRyan1986]

I'll take that as a no go

Here Is a slick and cheapish way to solve your problem. I read this somewhere else. Make yourself some cheap ghetto headers. This is my plan when i replace my 3.0. Cut out the cross pipe that goes behind the head. This pipe is what causes the excessive heat that is the main cause of the head gasket failure. after you cut the cross pipe turn the flanges so the remaining pipe points down. Then just make you own cross or y-pipe under the trans and BOOM no more headgasket problems. Atleast thats what the thing said that i read. It looks like it makes sense when i looked at the back of my parts engine. If you need i can take some pics this weekend for you and post them on monday.

 

[santanvalleydirt]

Here Is a slick and cheapish way to solve your problem. I read this somewhere else. Make yourself some cheap ghetto headers. This is my plan when i replace my 3.0. Cut out the cross pipe that goes behind the head. This pipe is what causes the excessive heat that is the main cause of the head gasket failure. after you cut the cross pipe turn the flanges so the remaining pipe points down. Then just make you own cross or y-pipe under the trans and BOOM no more headgasket problems. Atleast thats what the thing said that i read. It looks like it makes sense when i looked at the back of my parts engine. If you need i can take some pics this weekend for you and post them on monday.

^ I was going to say headers or heatwrap the crossover pipe as well, probably not good to toy with the the engine's internal workings or computer

 

[theking11863]

Here Is a slick and cheapish way to solve your problem. I read this somewhere else. Make yourself some cheap ghetto headers. This is my plan when i replace my 3.0. Cut out the cross pipe that goes behind the head. This pipe is what causes the excessive heat that is the main cause of the head gasket failure. after you cut the cross pipe turn the flanges so the remaining pipe points down. Then just make you own cross or y-pipe under the trans and BOOM no more headgasket problems. Atleast thats what the thing said that i read. It looks like it makes sense when i looked at the back of my parts engine. If you need i can take some pics this weekend for you and post them on monday.

I don't know if I wanna do that. Sounds sketchy lol. Pictures would be nice though!

^ I was going to say headers or heatwrap the crossover pipe as well, probably not good to toy with the the engine's internal workings or computer

Yeah except you want to just get new headers. Unless you're your gonna buy them its not happening anytime soon bruh

 

[Bad_Vision]

King, ultimately you will do want you want to do with your rig. But as me and the other "Elders" have said don't remove your stat. These engines run warm it's the nature of it. To keep cool a aluminum radiator and electric fan will solve your concern. But you absolutely have to fix your gasket issue before using it further.

Heat wrap and custom headers is more money thrown at something as simple as replacing the thermostat with a correct OEM part.

To you this seems like a huge deal but to us more experienced with these trucks have been down that road and made those mistakes. I have used all 4Runner engines in extreme cold -41f and extreme heat 123f and never had issues. So your making a mountain out of a mole hill.
You have a truck that was use to mild climate and took it into high heat area the gaskets thinned out and it went it's common if someone rebuilt it using crappy autozone gaskets. Use good parts and it won't have any issues.

 

[BigRyan1986]

I don't know if I wanna do that. Sounds sketchy lol. Pictures would be nice though!

I will get you some pics tonight after i get home. I had to work on my volvo this weekend so i didn't have a chance to go poke around with my 3.0. Ill go out and mess with it today

 

[theking11863]

I don't know if I wanna do that. Sounds sketchy lol. Pictures would be nice though!



I will get you some pics tonight after i get home. I had to work on my volvo this weekend so i didn't have a chance to go poke around with my 3.0. Ill go out and mess with it today

Alright thanks

 

[BigRyan1986]

Alright thanks

Not a problem. When i first read about it i thought the same thing until i boutght my new used engine for my runner and saw what they were talking about and it sounds way worse then it really is.