It might be different on the vehicle you own. this is just from my own experience and testing my email ronleggett94@gmail.com add me on snap chat cherokee ronnie my insta cherokee.ronnie m. profile.php?id...
Seriously, I saw someone ask this on Quora so I googled it. I started with the realization that if you remove the thermostat, that except at a good clip there isn't enough air to cool and it just keeps getting hotter and hotter till it seriously overheats. Up till here not one person said it was a bad idea to remove it. Or even suggested the possibility of overheat. Actually the complete opposite as in, it will never even get warm without a thermostat. I knew it but never realized how badly you could screw yourself taking advice off the internet. And a lot of them said they were long time mechanics. I was a mechanic specializing in brake and suspension and even I knew this. Thanks Ronnie.
Great video, awesome advice. I've known people to take out the thermostat and run water in the summer time thinking it was going to keep it cooler. They always have cooling issues, well, duh.. Always run a thermostat and with anti-freeze (50-50 mix). Love your vid's bro, your the XJ god, lol. Keep on keeping on bro. OlllllllO
Good info. I would have assumed it would run cooler. But given the mode that you tested it in it makes sense that it over-heated and I'm willing to beat that even if you were in 4h or even 2h creeping down a trail in 85-90deg heat it would still overheat. I think I will run a 195 in the Summer.
Try a 180 Tstat if your always in hot weather driving NOT COLD weather. The radiator efficiency with the fan is critical for air flow and cooling system efficiency. A dual core radiator will help if only a single row. Chrysler on some vehicles do this and call it HD cooling or part of the tow package in a old mini van with a 4 cylinder and a higher gear ratio in the trans axle allowing it to rev higher creating more heat but dissipated better with the larger radiator capacity as an example. Had one and it never ran hot even working it hard. Noticed a big difference when the radiator failed due to rott and replaced it with only a single row radiator since the dual core was not available at the time.HD trans cooler using the radiator and external cooler makes the difference also.
I change thermostats twice a year. 180 degree for summer and a 205 degree during the winter. Seldom ever will go above 210 unless there's a problem with the cooling system or over working the system such as AC on a very hot day 4W off road trekking. 1999 xj
My first car the thermostat went bad by staying closed. Replaced it. Was fine until one summer it didn't seem right. No temp gauge on that car. Checked it and the center parts, spring, etc were gone. Ran it that way until winter creeped in and replaced it.
I have a 2002 grand cherokee laredo 4.0, took out the thermostat 2 year ago following a recommendation from a friend. I leave in Miami so there is alot of heat (98 or more around summer) and alot of traffic; it has overheated 4 times already and had to replace a few pieces. My mechanic found out yhe problem since i forgot about taking the thermostat. Will install a new thermostat now on the weekend
What? You remove the Thermostat and your Car overheated? Impossible! I did that on my Dad's Blazer, the Engine is always cool. We drove 4+ Hours straight and no worries! OMG, I LOVE IT !!!
1991 xj inline six, I just threw the thermostat out, and things work great. I'll put one back in come November, but til then this POS will be shelved. Also a good tip, before installing it test it in boiling water to see if it opens.
It has everything to do with the ECU, Nothing else. No thermostat, you are in open loop. I don't see how you could possibly over heat without the thermostat.
Jeep designed them to run hot. mine blows hot air with in 1 and 1/2 miles from my house from over night and ice cold. also, as in running an auto when your engine is overheated will burn the ATF and can take out your transmission too. it is vital to have your cooling system up to spec and working as designed. and coolant in good condition.
I've read that they designed the I6 to run hot in several forums over the last two weeks after getting my 2000. I don't believe I have read why. Not trying to call you out on your statement but just curious if there was a reason.
They are designed to run at 210. I tried a 165 thermostat (you can choose from 165degrees to 230. for a thermostat) but when I used a 165 it ran to cool, used lots of gas and ran shitty..put 195 back in now runs great..plus don't use cheap fuel.
A few things for this. Probably with a mechanical fan but with electric fans and no thermostat mine stays around 180-200. I figured this out while doing a flush with an additive and thermostat out. I use k suspension fans and it’s always been great with thermostat but noticed a ton of rust in the block and heater core. Looks like someone ran water only for years in this thing. Hence the reason I wanted to flush everything. My radiator did have pressure in it with no thermostat once warmed up. I’m in Florida and It does great.
I live in Florida too. I’ve replaced my thermostat 6 times in a year and still end up with a thermostat inactive code. Only issue I have is if I’m staying in idle for longer than 10 mins
A very old mechanic told me never to run an engine without a proper thermostat as the coolant flows so fast through the block that it doesnt soak the heat to the coolant then transfer the heat properly to the radiator he said that without a thermostat it causes lots of air pockets mostly on the back cylinders and will finaley crack those cylinders. The people that designed the engine put it there for a purpose
Great test Ronnie! Engines are designed to run with the thermo in coolant system for best performance and engine life. My summers hit 90f and winters as cold as -30f. It is vital to have that thermo in there for the engine to run properly and avoid damage in my crazy temperature ranges. The thermo helps keep the engine in that 195f to 215 sweet spot for optimum operation no matter the temp. If people are having over-heating problems in their 4.0's all they have to do is follow your advice in previous videos. Flushing the system, throw 50-50 in there and used distilled water, not tap can work wonders.
Mines a 2001 wj and it’s stay cold no matter what and stays at the first quarter. I’ve changed thermostat and made sure there’s no air bubbles I mean I think so lol but I don’t know what to go off by anymore
Would engine size matter? I ran a f150 with a 400 . A engine known to over heat at least here. I ran it with out a thermostat from 90 - 97 for everything never had any more over heating problems. It took a bit more time to warm up during the winter. But hell I just put a jacket on for those 15 or so days. Fl.
Ihave this problem..bad thermostat so a friend of mine took it out and we put in a new radiator and hose. On the road its cool but in traffic my jeep overheated but cooled down once iwas cruising again
Honestly if a jeeper is having cooling issues and they have all good hardware (radiator, water pump, thermostat and radiator cap) then its time for a flush with some of that break up stuff designed for engine cooling systems. I have a 300k xj that never strays above 195 under load or coasting regardless of the outdoor temps so its not as if these systems are badly designed.
All cooling-systems have a built-in restriction, it is called the radiator...........it naturally slows the flow of coolant, giving it more time to cool. I have pulled the t-stat on various vehicles I have owned, they NEVER ran hotter, but much cooler.
I thought about installing a 180* thermostat. That would give the coolant system back pressure needed. Now how much more gas consumption or any other issues.
I don't run a thermostat in my xj and I live in Florida no over heating issues. I do have an electric fan which I switch on when I hit about 200/210 in stand still traffic or wheelin the temperature comes right back down ( this is in 90-98 degree weather) . I've sat in rush hour traffic with the AC blasting and with help from the electric fan no problems at all. I would be unsure about adding a thermostat now cos as the say "if it ain't broke don't fix it". I also ran no thermostat in my chevy express 2500 with no issues or no extra fan
We By-Pass them all on our Cars / Trucks. I also made Video of them under my Channel too. I actually just made a New Vid on my Channel running with By-Pass and NO Fan.. Yea, I was brave, LOL. I have a 45+ Minutes Video Engine running with a By-Pass Thermostat and No Fan !!!
I have no thermostat in my wrangler 4 L. It runs phenomenal. It gets up to about 190° and here in Florida. That’s what I want so I have no idea why your jeep is it overheating but here everyone takes their thermostat out.
If the engine overheats without thermostat, there must be other issues. Fan might not be working properly, engine might have issue in the head gasket, etc.
By pass it completely if you can. I did that on my Dad's Blazer, the Engine is always cool. We drove 4+ Hours straight and no worries! OMG, I LOVE IT !!!
Having a thermostat is better, especially if you have electronic radiator fans. No thermostat would result in the temperature in the radiator being exactly the same as what's in the engine. The electronic fans would work harder, your engine will never be replenished by cooler liquid because the coolant hasn't been sitting in the radiator long enough.
Shouldn't cooling ability of radiator should be greatest with max flow? The temp sensor is adjacent to the thermostat...could it be that the sensor is more emersed with thermostat out, and that is why the temp reads higher then?
If the Jeep was set up to run without a Thermostat they would not install one. All Jeep's seem to run a little hot my 2000 XJ in (the heat) runs from 210 to 212 a little over half way then you can see when the Thermostat opens the temp drops down to a shade under 210 and the cycle begins again. In the Fall and Winter months the Temp goes up to 210 Thermostat opens and the Gauge drops to about 208 a little below the Half then the cycle begins again. No vent's in Hood. There are 2 kinds of cooling systems installed in XJ's older versions have a Closed System the Radiator has no Cap, you can only add coolant threw the overflow bottle. This is called a Closed System. The second is a Vented System the Radiator has a 16 pd Cap and the overflow bottle is vented. Many people choose to switch from the Closed System to the Vented System that's on all 97 to 2001 Jeep XJ's you can find the parts you need to do this in any Bone Yard. Many of the older Renix Models have a closed system. Bottom line Jeep XJ's with the 4.0 Engine run a little hot.
I've been a chevy guy ,and am. not a mechanic ,but race a dirt track car . And we dont consider a motor hot until over 230 degrees and think 210 is normal . At least on a sbc . Is 210 really a over heating situation . My Xj runs 210 all day
Thanks for the video. I just had my thermostat go bad on my 2005 Volvo XC90 2.5T . It takes about 35 mile for me to get to my mechanic and the engine is overheating , getting all kinds of warnings and the collant is boling and evaporating. Is it safe to drive with all this for 35 miles ?
By pass it completely if you can. I did that on my Dad's Blazer, the Engine is always cool. We drove 4+ Hours straight and no worries! OMG, I LOVE IT !!!
What would cause my jeep not to shift right it has a lag and I thought was transmission so put another one in and another torque converter and same results I need help and its sadly 2wd idk if could be the shift sensor or rear end please let me know
my jeep runs fine and i replaced everything for cooling. new pump, radiator, fans, sensors, thermostat. i did remove the clutch fan and now just electric fans. for some reason the gauge always shows around 215. bad sensor, because i removed the clutch fan causing this. should i go with a lower temperature thermostat? works fine but always shows like 215. before it was always at 210.
+Texas Car Nerd - People Drill two 3/16" Holes in the Thermostat to have it lower. Or you can do with a Lower Temp like 180F. They do sell them at 180F. I have a few Vids on By-Pass and Test Vids too in my Channel, check it out... It might be useful to you.
You took out the fan clutch..thats driven by horse power not battery power..do drill holes in a 180°...Ive done this to a 454 I have..Upgraded from heavy duty fan clutch to a severe fan clutch..Im in a 115° desert too.
You will because the car will keep dumping fuel to get it up to temp..If your computer thinks the engine is cold youll use more fuel..all that raw fuel will give you bore wash..washing all the oil additives away causing engine wear..engine up to temp burns the carbon..
Drove my van though the southwest in a broiling heatwave, no t-stat. The it-runs-hotter-with-no-thermostat urban-legend must have worked in reverse on my van......roasting weather and going up hills, but my van stayed near 170-degrees the whole time.
I did that too and then I By-Pass it. By-Pass it completely if you can. I did that on my Dad's Blazer, the Engine is always cool. We drove 4+ Hours straight and no worries! OMG, I LOVE IT !!!
