Questions about thermostat change

rebelles

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To make a long story short - I am pretty certain that the Thermostat in my 01 is stuck open (running cool all time and receipt from prior shop install says it has a Napa Safe T stat 195 in it). I have read all the info on preferred thermostats for the 4.0 TJ. However, I sort of need to fix today when only the chain auto parts stores are open and I don’t see any locally listing the recommended Stant. The two questions are:
1 - is there any recommended thermostat to pick up at Oreilys, Auto Zone or Advance Auto (that’s my options).
2 - any suggestions on how much coolant to drain out to make a mess when pulling the house (I would prefer not to drain all out). The coolant is brand new after a recent water pump replacement.
 
When I replaced my thermostat on my '01 4.0L due to the same problem of being stuck open; I installed a STANT Superstat thermostat along with a Felpro gasket which has a red impregnated sealant.
I drained enough coolant that I couldn't see a level in the radiator which amounted to a 2 quarts.
Ensure to drill a 1/8" hole in the flat surface to allow for faster air bleed when refilling with coolant.

https://www.amazon.com/dp/B000C7YRNM/?tag=wranglerorg-20
 
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When I replaced my thermostat on my '01 4.0L due to the same problem of being stuck open; I installed a STANT Superstat thermostat long with a Felpro gasket which has a red impregnated sealant.
I drained enough coolant that I couldn't see a level in the radiator which amounted to a 2 quarts.

https://www.amazon.com/dp/B000C7YRNM/?tag=wranglerorg-20
Thanks. I have access to the felpro gasket you mentioned (same type I used on water pump) but not the Stant thermo.
 
Thanks. I have access to the felpro gasket you mentioned (same type I used on water pump) but not the Stant thermo.

Almost every time I go in to the auto parts store; they need to order the part IF I want a part that is not a Chinese knock off.
Since you may need to order it thru the AP store; just cut out the middle man and order it yourself online.
 
Almost every time I go in to the auto parts store; they need to order the part IF I want a part that is not a Chinese knock off.
Since you may need to order it thru the AP store; just cut out the middle man and order it yourself online.
Thanks. If it comes to having to order I will and usually do it myself but need one today so looking for info if there is really one of the lower priced ones that is better than the other. Down the road if I end up doing other coolant work, etc. I can put in a better part.
 
Ive used several from Orieleys/Kragens. Blue and white box, a Murray brand perhaps made in Israel?? Ive never had any problems with them.
 
Ive used several from Orieleys/Kragens. Blue and white box, a Murray brand perhaps made in Israel?? Ive never had any problems with them.
Do you remember if it was the Murray Plus or Ultra. The ultra looks like it’s all stainless and the plus. Has come copper. I can tell if the Ultra is a fail safe type which I want to avoid (I doesn’t say).
 
X2 to avoiding anything that says "fail safe". It shouldn't be a fail safe if the box it comes in doesn't have failsafe printed on it anywhere. Avoid Duralast from Autozone and almost all other store brands. X2 to the Murray recommendation above if you can't find a Duralast. I'd think NAPA's best model should be fine, just make whatever you choose has the proper 195 degree rating.
 
X2 to avoiding anything that says "fail safe". It shouldn't be a fail safe if the box it comes in doesn't have failsafe printed on it anywhere. Avoid Duralast from Autozone and almost all other store brands. X2 to the Murray recommendation above if you can't find a Duralast. I'd think NAPA's best model should be fine, just make whatever you choose has the proper 195 degree rating.
Just picked up both to compare. They look identical in structure (I don’t see any extra parts that would lock it back if it got past a certain temp). Just tested it on the stove and seems to operate in normal fashion. It is a little heavier in weight that the Plus model which I guess due to the difference in the stainless parts versus copper.
 
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If you drain a little over a gallon from the radiator you can pull the housing without spilling much. You are going to have to bleed the system regardless after pulling the thermostat. Draining half vs all from the radiator wont change that. You don't need more than an 8qt catch pan for the job.
 
If you drain a little over a gallon from the radiator you can pull the housing without spilling much. You are going to have to bleed the system regardless after pulling the thermostat. Draining half vs all from the radiator wont change that. You don't need more than an 8qt catch pan for the job.
I thought drilling the hole in the thermostat was supposed to help reduce the need to bleed air out the system?
 
Picture comparison

A5FEC829-8E99-4188-BDFB-F147D5BED387.jpeg
 
The hole reduces the time required for the process. If you have time to start the system once and let it warm so the thermostat opens, let it cool and refill you don't need the hole at all. Some people don't have the time to wait so they drill the hole. I just did mine and the whole process took less than an hour without a the hole. I did have to top off the overflow after my first real drive but other than that it wasn't a big deal.
 
I pulled the thermostat out and as expected it was locked open. I went ahead and installed the murray Ultra model after drilling a 1/8” hole on the flange and positioning it at 12 o’clock on the install. I tried the trick of jacking up the drivers front and slowly poured all the fluid I caught from draining down the radiator except for approx 8 ounces. (I drained out just a little over a gallon). I poured the 8 ounces into the overflow tank. I ran it around for a little bit to get to operating temp and then let idle in the driveway a while. Seems to be operating as it should holding around 200 on the dash gauge. I shot it with an IR gun and seems about right on the thermo housing head area. Hopefully the thermo functions fine. This isn’t a daily driver and I won’t be putting a lot of miles on it (May end up as my camp Jeep actually). So we shall see
 
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When I replaced my thermostat on my '01 4.0L due to the same problem of being stuck open; I installed a STANT Superstat thermostat along with a Felpro gasket which has a red impregnated sealant.
I drained enough coolant that I couldn't see a level in the radiator which amounted to a 2 quarts.
Ensure to drill a 1/8" hole in the flat surface to allow for faster air bleed when refilling with coolant.

[URL]https://www.amazon.com/dp/B000C7YRNM/?tag=wranglerorg-20[/URL]

The 1/8th hole is the question that I have had all day. My Stant did not have one. Thanks
 
Anyone find a quality thermostat ??? Stant is now Motorad, Motorad has always sucked (I’ve given them a few chances, they’re unstable at best) …

Edelbrock’s made in USA is now Chinese. Mopar is also Motorad. Robert Shaw is gone and Mr Gaskets Chinese copy is junk.

Flowkooler states they sell a Robert Shaw. Or should I give Motorad another chance ???
 
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