diverscale
Member
For those in celcius.
Was running at 91-93 celcius at 12
Now running at 87-88 celcius at 6
Was running at 91-93 celcius at 12
Now running at 87-88 celcius at 6
Coolant frustration: new thermostat installed wrong way?
- Thread starter seabun
- Start date
seabun
Member
Update 3: Thermostat flipping=15° drop, across band.
When my radiator funnel arrived, I borrowed a torque wrench from AutoZone and set to draining the coolant and flipping the thermostat.
First discovery: Alamo had not used the Red long life coolant but the Pink coolant that was developed in 2003 aka after our trucks. After reading posts where people had difficulty finding Red, I called my local dealers: They both said they put Red coolant in all 2002 and older vehicles and had plenty. Cool.
Back home: got to thermostat, flipped it, triple checked the week-old gasket was alright, torqued the inlet back down, filled funnel with RED coolant+distilled water and burped system for 15 minutes. Closed hood.
After driving for over a week in outdoor temps ranging from 102°-90°, with A/C on high, low, off, idling in traffic and cruising the highways, I am confident that flipping the thermostat had the intended effect.
@12 + pink coolant: rad temps were between 203°-208° (highway-idling).
@6 + red coolant: rad temps have consistently been between 188°-192° (highway-idling).
I appreciate everyone's two cents on their experiences, and fwiw add me to the jiggle down camp. Finally, I have peace of mind about my greatest 4runner gremlin being pacified. Sometimes if you want something done right, you gotta do it yourself!:banana:
When my radiator funnel arrived, I borrowed a torque wrench from AutoZone and set to draining the coolant and flipping the thermostat.
First discovery: Alamo had not used the Red long life coolant but the Pink coolant that was developed in 2003 aka after our trucks. After reading posts where people had difficulty finding Red, I called my local dealers: They both said they put Red coolant in all 2002 and older vehicles and had plenty. Cool.
Back home: got to thermostat, flipped it, triple checked the week-old gasket was alright, torqued the inlet back down, filled funnel with RED coolant+distilled water and burped system for 15 minutes. Closed hood.
After driving for over a week in outdoor temps ranging from 102°-90°, with A/C on high, low, off, idling in traffic and cruising the highways, I am confident that flipping the thermostat had the intended effect.
@12 + pink coolant: rad temps were between 203°-208° (highway-idling).
@6 + red coolant: rad temps have consistently been between 188°-192° (highway-idling).
I appreciate everyone's two cents on their experiences, and fwiw add me to the jiggle down camp. Finally, I have peace of mind about my greatest 4runner gremlin being pacified. Sometimes if you want something done right, you gotta do it yourself!:banana:
StreetCreeper
New member
I know some guys here are perfectly fine running their trucks at 200°+ and I'm not one to say that you can't or shouldn't – but I really don't understand not wanting the extra overheat protection that an additional 10-20° difference would give you. I know it's splitting hairs – but I can climb mountains fully loaded doing 65 and not break 198°. Obviously I'm not pulling an overloaded trailer full of golden dildos over the Rockies at high noon – but my truck is under a good amount of stress.
By the same token – I can sit all day in 107° heat in a parking lot with the A/C on max blowing 40° air while the ambient air intake temp (according to ScanGauge) is at 150°+ and still sit around with 190° coolant. So guys that are hitting 200°+ just driving around are probably dealing with a 12 o'clock jiggle valve or they have a failing cooling system.
These trucks are perfectly capable of handling high heat situations so long as the cooling systems are maintained properly and monitored closely.
By the same token – I can sit all day in 107° heat in a parking lot with the A/C on max blowing 40° air while the ambient air intake temp (according to ScanGauge) is at 150°+ and still sit around with 190° coolant. So guys that are hitting 200°+ just driving around are probably dealing with a 12 o'clock jiggle valve or they have a failing cooling system.
These trucks are perfectly capable of handling high heat situations so long as the cooling systems are maintained properly and monitored closely.
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pluton
Senior Member
FYI: 180º thermostats are for turboed/supercharged engines. Normal 5VZ-E engines take the 190ºF(88ºC) thermostats.
And, yes...why anyone would choose to run their engine at 203ºF when they could run it at[ the recommended temperature of]190ºF is beyond me. Maybe they like their steaks well-done as well?
And, yes...why anyone would choose to run their engine at 203ºF when they could run it at[ the recommended temperature of]190ºF is beyond me. Maybe they like their steaks well-done as well?
seabun
Member
[MENTION=115590]StreetCreeper[/MENTION], [MENTION=89081]pluton[/MENTION], precisely what I'm thinking as well. I would much rather orbit optimal and save pushing it for rare exceptions, not the other way around. I feel better with that extra 15° buffer for sure. Learned more about the truck, and some tools, in the process.
Recommended thermostat for normally aspirated 5VZ-FE is 180 F or 82 C.
Don't know what it should be for supercharged.
Thermostat temp does not necessarily mean that's the recommended operating temperature.
phattyduck
Elite Member
Let me see if I can answer/clarify a few things:
The 5VZ (and probably 3RZ) has an 82*C/180*F thermostat - that is the setting for the water INLET temp to the motor. In the case of the 5VZ, this leads to an engine outlet temp of 188*F - 191*F under most operating conditions. The temp sensor for both the dash and ECU are at the outlet of the motor, the thermostat is at the inlet.
As a correction: Thermostats are continuously variable devices. A correctly operating one will allow just the right mix of recycled (from the coolant bypass hose) and cooled (from radiator) coolant to achieve the desired coolant temperature. If coolant temp goes above the set number, that generally means that the coolant flowing out of the radiator is hotter than the thermostat temp (thermostat fully open). This happens more often on cars with electric fans. The 4Runner has a mechanical fan and doesn't have this problem, generally...
Boiling coolant:
1 - The coolant in the cooling system changes volume with pressure, whether or not there is any boiling happening.
2 - There can be localized areas of coolant that are MUCH hotter than the average coolant temp. Remember, it flows right next to the cylinders! This is the reason you need boiling protection to 250*F+ even if average temps are below water boiling temps. This is achieved both by pressurizing the cooling system (it does pressurize before boiling due to thermal expansion) and antifreeze/coolant in the system (raises boiling temp above water alone).
-Charlie
octanejunkie
Elite Member
You're also not saying you haven't pulled said trailer before.
This place is better with you here
DK327
Member
Mystery remains! Was the temp drop due to jiggle valve position or changing the coolant from pink to red!
op2:
Scramble
New member
I think he's more into pushing golden dildos than pulling....
StreetCreeper
New member
You're also not saying you haven't pulled said trailer before.
This place is better with you here
StreetCreeper
New member
Scramble
New member
Attachments
StreetCreeper
New member
I don't want you to get into any trouble here on the forum – so I changed the "indecent" part of that picture to something seemingly benign yet still equally offensive to the senses.
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You made too many changes to know it was the thermostat flipping that did it. You change the orientation of the t stat, changed the coolant, and possibly (probably) removed more air from the system than had previously been done by the dealership that was in a hurry to get your vehicle out of their bay.
At any rate, glad the temps are back down.
StreetCreeper
New member
Red coolant doesn't make any measurable difference in cooling. I also highly doubt that he simply burped the system better when he reoriented the t-stat either. It's a known phenomenon that the t-stat will most often drop or raise the coolant temps depending on orientation. Not sure why some people don't want to believe this...
I'm pretty sure DK327 was just having fun when he mentioned that the "mystery remains" because the coolant was changed out at the same time. I run green coolant and my temps are 190°~ all day everyday. My T-stat is at 6 o'clock too.
phattyduck
Elite Member
LOL. No mystery. It is the jiggle valve position.Mystery remains! Was the temp drop due to jiggle valve position or changing the coolant from pink to red!
http://www.toyota-4runner.org/3rd-gen-t4rs/154750-toyota-red-coolant-vs-toyota-pink-pre-mixed.html
https://www.toyotaparts.metro-toyota.com/ENGINE_COOLANT_COLOR_CHANGE_T-PG010-02.pdf
If pink is mixed to a red system (without a flush) it loses the 'super long life' capability and is then equivalent to the 'long life' of the red. That's it.
I stick with Red because I can easily run a 40/60 mix (coolant/water) for more heat removal capacity. I also work on my cars often enough that I don't have any interest in the longer life of the pink stuff.
-Charlie
I tend to agree with everything you said, but some people notice a difference, others dont. There are enough posts each way.
TheDurk
Elite Member
The weight of experience is heavily in favor of the 6 o' clock T-stat reducing temps on the 5VZ-FE. I've been on here for 10 years and you will have to trust me on this. It's not a case of some posts either way.
On the other hand, the color is related to anti-corrosion additives and that's it. The only difference that matters in the liquid as far as temps go is the mix percentage of ethylene glycol (the more water, the better the cooling, as water has a higher thermal density).
octanejunkie
Elite Member
I don't want you to get into any trouble here on the forum – so I changed the "indecent" part of that picture to something seemingly benign yet still equally offensive to the senses.
You forgot the two indecent biebles at the base :llama:
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