Normal coolant temps

[A.Wilson013]

Since replacing my heads I get antsy whenever my temps go over 190 haha...

I run a factory T-stat and my temperature, seemingly regardless of ambient temp, is locked on 188. While climbing a STEEP pass out in Idaho this summer it got up to 195... Haven't seen it over that.

I used to run a TRD t-stat (whatever those are rated at) and was always at 193 or so. Saw temps, while wheeling on a hot summer day, hit 205 once.

 

[mtbtim]

I believe I will. I'd much prefer running cooler.

Yeah, it doesn't make a whole lot of sense how that little jiggle valve can have such an effect on your coolant temps but it does. It's been proven by tons of people that were running high temps and a simple switch of the jiggle valve position fixed it.

Here's a video that shows changing out the thermostat. If you want to jump right to the thermostat part, start watching at 13:00 play time.

<iframe width="560" height="315" src="https://www.youtube.com/embed/A8OTtggtQnc" frameborder="0" allowfullscreen></iframe>

 

[mtbtim]

Since replacing my heads I get antsy whenever my temps go over 190 haha...

I run a factory T-stat and my temperature, seemingly regardless of ambient temp, is locked on 188. While climbing a STEEP pass out in Idaho this summer it got up to 195... Haven't seen it over that.

I used to run a TRD t-stat (whatever those are rated at) and was always at 193 or so. Saw temps, while wheeling on a hot summer day, hit 205 once.

I use to run around 188-190 most of the time too. However, after replacing my radiator, thermostat and fan clutch, I'm actually running a little warmer now, 192-194. The radiator and thermostat are OEM and the fan clutch I used is an Aisin that's supposedly the same as OEM. And, the jiggle valve is definitely in the 6 o'clock position. I'm almost thinking the new thermostat with a newer, stiffer spring isn't opening as far as the old one did. I think the highest temp I've seen is 199 climbing a steep grade.

I am running an external trans cooler affixed to the AC condenser so that could be affecting the airflow efficiency through the radiator.

 

[Keith M]

Tim,
I really appreciate your videos. These are a huge service to the community. And you do such a good job too.

Well done sir.

Yeah, it doesn't make a whole lot of sense how that little jiggle valve can have such an effect on your coolant temps but it does. It's been proven by tons of people that were running high temps and a simple switch of the jiggle valve position fixed it.

Here's a video that shows changing out the thermostat. If you want to jump right to the thermostat part, start watching at 13:00 play time.

<iframe width="560" height="315" src="https://www.youtube.com/embed/A8OTtggtQnc" frameborder="0" allowfullscreen></iframe>

 

[mtbtim]

Tim,
I really appreciate your videos. These are a huge service to the community. And you do such a good job too.

Well done sir.

Thanks for the kind words Keith. Glad you're getting something out of the videos [MENTION=102606]infamousRNR[/MENTION] (aka Sean) and I are making.

We've got some new ones coming out very soon: Toytec Body Lift, Complete Toytec Suspension Lift, 5th Gen UCA Replacement and Front Spring Replacement (installed Total Chaos UCAs) (includes the necessary KDSS recalibration).

We've also got a Rear Axle seal Replacement with 3rd Member Swap coming at the end of this month and unfortunately for Sean, we'll be showing How to Replace an Automatic Transmission very soon as well.

 

[LittleCaesar]

I use to run around 188-190 most of the time too. However, after replacing my radiator, thermostat and fan clutch, I'm actually running a little warmer now, 192-194. The radiator and thermostat are OEM and the fan clutch I used is an Aisin that's supposedly the same as OEM. And, the jiggle valve is definitely in the 6 o'clock position. I'm almost thinking the new thermostat with a newer, stiffer spring isn't opening as far as the old one did. I think the highest temp I've seen is 199 climbing a steep grade.

I am running an external trans cooler affixed to the AC condenser so that could be affecting the airflow efficiency through the radiator.

You need to burp all the bubbles out of the cooling system. When I got most if not all mine out the temp dropped from 193 to 190. This may be the hardest engine I have ever encountered to get all the air out of the cooling system.

If you don't have one of these, make it to be the next tool you buy:
Bottom-line pricing on Lisle - 24680 at ToolTopia.com

Park on a hill, attach the funnel and run the 4runner for a good ten minutes. Your driveway looks as if the incline would be sufficient. Run the heat on HOT or max. Let it cool. Then see what the temps look like.

 

[mtbtim]

You need to burp all the bubbles out of the cooling system. When I got most if not all mine out the temp dropped from 193 to 190. This may be the hardest engine I have ever encountered to get all the air out of the cooling system.

If you don't have one of these, make it to be the next tool you buy:
Bottom-line pricing on Lisle - 24680 at ToolTopia.com

Park on a hill, attach the funnel and run the 4runner for a good ten minutes. Your driveway looks as if the incline would be sufficient. Run the heat on HOT or max. Let it cool. Then see what the temps look like.

I think you were the person who recommended I buy this kit a while back. It's been sitting in my Amazon cart for a long time now. I'm going to buy it and try it out and see if air bubbles trapped in the system are the cause of the slightly higher temps I'm seeing. Thanks!

 

[jgue467]

I'd suspect the thermo too. Guessing ya' went with toyo oem?

Mine did the exact opposite, went from 195-198 to 185-188, I could see scratches on the upper part of the thermo where it was sticking partly closed. Luck and enjoy. :cowboy:

 

[mtbtim]

I'd suspect the thermo too. Guessing ya' went with toyo oem?

Mine did the exact opposite, went from 195-198 to 185-188, I could see scratches on the upper part of the thermo where it was sticking partly closed. Luck and enjoy. :cowboy:

If you were referencing my post, yes, I definitely used an OEM thermostat. I did a search and I did find others who said after they replaced their old thermostat with a new OEM that they were running a little hotter, exactly what happened to me. And, one of the people actually put his old thermostat back in and he was running cooler afterwards.

I do have my old thermostat and I just might try out swapping it back in the next time I'm due to renew my coolant. But first, I'm going to try out the Lisle funnel that [MENTION=69868]LittleCaesar[/MENTION] recommended and see if that drops my temps.

 

[Bijan]

I used to run a TRD t-stat (whatever those are rated at) and was always at 193 or so. Saw temps, while wheeling on a hot summer day, hit 205 once.

Well thats f*cked

 

[Bijan]

my symptom: heater is luke warm... it used to be HOT.

Thermostat?

....

 

[catrains]

....

if the engine temp is normal 200deg F then check that the heater hoses both are hot . if they are not both hot then the core maybe plugged up. using the dirty tap water and other non distilled water will do it. or if someone mixed different coolants into the system that can create some nasty goop..

if the hoses are both hot then a HVAC temp door problem ,..

 

[Jayjayb96]

I think you were the person who recommended I buy this kit a while back. It's been sitting in my Amazon cart for a long time now. I'm going to buy it and try it out and see if air bubbles trapped in the system are the cause of the slightly higher temps I'm seeing. Thanks!

I got the same thing happening to me. When i first bought from the PO temps skyrocketed a week later so immediately installed new oem radiator, cap, fan clutch; stant 170 tstat and b&m tranny cooler. My temps have been in the 200 range and have always thought it was high but now im boosted too.

I should probabaly try and burp the system again. [MENTION=120071]mtbtim[/MENTION] watch your vid on this long time ago but when you decide to try and burp your system let me know. Id like to be there for that..then i can try and do mine sometime

 

[mtbtim]

I got the same thing happening to me. When i first bought from the PO temps skyrocketed a week later so immediately installed new oem radiator, cap, fan clutch; stant 170 tstat and b&m tranny cooler. My temps have been in the 200 range and have always thought it was high but now im boosted too.

I should probabaly try and burp the system again. [MENTION=120071]mtbtim[/MENTION] watch your vid on this long time ago but when you decide to try and burp your system let me know. Id like to be there for that..then i can try and do mine sometime

Hey Jay, I'm meeting up with Paul at my place Friday morning, the 13th, to recalibrate his KDSS system and remove a spring spacer. If you want, you can join us and we can burp your coolant system with that Lisle funnel system. I ordered it today with Amazon Prime so I should have it in a couple days. I'll most likely try it out on my rig on Wednesday. If Friday doesn't work for you, I could help you Wednesday or Thursday too. Let me know.

 

[Jayjayb96]

Hey Jay, I'm meeting up with Paul at my place Friday morning, the 13th, to recalibrate his KDSS system and remove a spring spacer. If you want, you can join us and we can burp your coolant system with that Lisle funnel system. I ordered it today with Amazon Prime so I should have it in a couple days. I'll most likely try it out on my rig on Wednesday. If Friday doesn't work for you, I could help you Wednesday or Thursday too. Let me know.

Thanks tim,

I would love to but i work weekdays and saturdays. Although ill be quitting my job soon so after that Ill have more free time haha

 

[mtbtim]

Thanks tim,

I would love to but i work weekdays and saturdays. Although ill be quitting my job soon so after that Ill have more free time haha

Sean, Jordan and I are going to do an rear axle seal job and 3rd member swap on Jordan's rig on Sunday the 22nd. You're welcome to stop by and use the Lisle funnel while we're working on Jordan's truck.

 

[Keith M]

Jiggle valve victory!

Okay...Thanks for the encouragement guys. Over the weekend, I looked at the t'stat/Jiggle valve (installed at the dealer 2 weeks ago). It was installed with the JV at 12 o'clock. I rotated it to 6 o'clock. Temps went from 204 down to 187. A 17 degree decrease.

I never would have believed it....but I do now. I'd tell the dealership they were mistaken, but I don't believe they would believe it either.

Over the last week, I took my '01 in for several things (dealer), one of which was to have them let me know if a running temp of 204 degrees was excessive. They said it was. They then replaced my t'stat (installed in 2014), replaced the radiator cap because they said it was cracked and charged be $202.

After taking possession, I rechecked (via OBD2 Fusion) and it was running 204 degrees. I took it back, another mechanic confirmed 204 was "perfect" and they refunded my $$.

When I asked them about where they positioned the "jiggle valve" they told me it made no difference and was....."not a factor in controlling the operating temp of the engine".

I am not sure what to do at this point.

 

[mtbtim]

If you were referencing my post, yes, I definitely used an OEM thermostat. I did a search and I did find others who said after they replaced their old thermostat with a new OEM that they were running a little hotter, exactly what happened to me. And, one of the people actually put his old thermostat back in and he was running cooler afterwards.

I do have my old thermostat and I just might try out swapping it back in the next time I'm due to renew my coolant. But first, I'm going to try out the Lisle funnel that [MENTION=69868]LittleCaesar[/MENTION] recommended and see if that drops my temps.

I used the Lisle funnel kit and no change with my coolant temps. I put the truck in my driveway at a slant with the front end being the high point. I ran the engine to operating temperature, put both the front and rear heaters on high, and ran the engine for 10 minutes. The only thing I didn't do was let the engine cool off. Didn't see how letting the engine cool off with the funnel in the radiator would change anything. I took it for a drive afterward and my coolant temps are still mostly between 192-194 and sometimes hit 196 at a stop.

This change in temps happened right after I installed my new radiator, external trans cooler and new thermostat. I think I'm still going to hold onto my theory that the new thermostat is the culprit for the change. When it's time for my next coolant renewal, I could drain the coolant into a clean bucket, replace the new thermostat for the old (I kept it), pour the coolant back in and see if the temps go back to what I was originally seeing (188-190) when I first got my OBD II reader and the Torque Pro app. Or, I can just say screw it and not worry about a 4-6 degree temperature change.

 

[shahsmerdis]

I think you were the person who recommended I buy this kit a while back. It's been sitting in my Amazon cart for a long time now. I'm going to buy it and try it out and see if air bubbles trapped in the system are the cause of the slightly higher temps I'm seeing. Thanks!

I have one, I used it to bleed, I bleed it pretty long, Still at ~200 in summer heat. I never replaced the tstat myself or know what the temps were before we did the rad swap. But that bleeder isn't going to magically drop the temp, actually its not so spill free. if you are not careful it can weep in between the two parts. It did help for me for my first major repair so overall a good investment, and since tim you work so many cars its probably worth it to have.

edit dam, I wish I got to this post sooner, I would have advised you it probably wouldn't have made a difference. Though its still very handy tool to have. Amazon has a very nice return policy of course if you don't want it.

 

[mtbtim]

I used the Lisle funnel kit and no change with my coolant temps. I put the truck in my driveway at a slant with the front end being the high point. I ran the engine to operating temperature, put both the front and rear heaters on high, and ran the engine for 10 minutes. The only thing I didn't do was let the engine cool off. Didn't see how letting the engine cool off with the funnel in the radiator would change anything. I took it for a drive afterward and my coolant temps are still mostly between 192-194 and sometimes hit 196 at a stop.

This change in temps happened right after I installed my new radiator, external trans cooler and new thermostat. I think I'm still going to hold onto my theory that the new thermostat is the culprit for the change. When it's time for my next coolant renewal, I could drain the coolant into a clean bucket, replace the new thermostat for the old (I kept it), pour the coolant back in and see if the temps go back to what I was originally seeing (188-190) when I first got my OBD II reader and the Torque Pro app. Or, I can just say screw it and not worry about a 4-6 degree temperature change.

I tried the Lisle funnel to burp the system again and no change to my coolant temps. I ran the engine for 15 minutes at operating temperature with both heaters on full blast. I even ran the engine at around 1500 rpms for at least 5 or the 15 minutes. I was watching the funnel from inside the truck and I could see bubbles coming up. When no more bubbles were coming up, i took it for a test drive and I'm still running around 192-196. Pretty frustrating since I was actually running cooler before all the work. It's still my theory that the new thermostat spring being new doesn't open quite as far as the old one.

I'm sick of wondering if the new thermostat is the culprit so I'm going to drain my coolant into a clean bucket, put my old thermostat back in (luckily I kept it) and see if my theory is correct. If this doesn't do it, it might be the Aisin fan clutch not working as good as the OEM one I replaced.