Question: Tacoma normal water temp?

[01tundra]

Exact same thing happened to my Tundra (4.7L) after replacing the timing belt, water pump, t-stat with all factory Toyota parts this past Spring. It used to run around 185F, but after I installed the new water pump it now runs 190F-193F without A/C and 197F with the A/C running on a hot day. I've seen it get up to 207F while pulling a long grade with the A/C running.


I even pulled the new t-stat and replaced it. I did switch from the "red" to the "pink" pre-mixed Toyota coolant, but I did a complete flush a few times now and no change......makes me want to rip the scan gauge out of the dash. The factory temp needle stays about in the center like it always has.


Something's wierd about this.....just can't figure out what's going on.

Since the operating temperature hasn't changed with various t-stats in it, it makes me suspicious of the factory water pump. I'm wondering if it isn't moving as much water as my original one was.

 

[sovereign]

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[Shadow]

^ My 2006 Tacoma runs in the 180s. ??

 

[Shadow]

There were a couple of threads on this topic over at 4runner.org


http://www.toyota-4runner.org/3rd-g...radiator-etc-today-interesting-discovery.html


http://www.toyota-4runner.org/3rd-g...nt-running-temps-2-different-thermostats.html


I'm beginning to wonder if Toyota's got some bad t-stats. ?? I'm going to order another aftermarket 180 degree t-stat and swap it in to see what happens.

 

[sovereign]

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[Shadow]

All thermostats I've seen were stamped with 82 C which is 180 F. This includes the one in mine originally and the two new ones I bought from the dealership.

 

[sovereign]

.

 

[Shadow]

I have a 3.4L V6 in an 02 4runner. I'm pretty sure the stock t-stat is the same for both taco and 4r. I'll check.

Edit: Part number for t-stat looks to be the same for both.

When I bought the t-stat from the dealership, I asked if there were althernate t-stats which opened at different temps-- i.e. 180 and 190. He said no. Who knows.

To be clear, I have a 2002 4runner and a 2006 Tacoma.

 

[cruiseroutfit]

From the FSM:
Thermostat Valve opening pressure - 80 – 84°C (176 – 183°F)
Valve lift at 95°C (203°F) - 8.5 mm (0.335 in .) or more

I can't recall what the TRD version of the thermostat opens at, I want to say it was 170*F? I know Stant has a 170* available for the Tacoma which likely has an actual opening range of say 165* to 175* F

 

[01tundra]

All thermostats I've seen were stamped with 82 C which is 180 F. This includes the one in mine originally and the two new ones I bought from the dealership.

Same here, every one I've put in mine has been the factory 82 C t-stats. I asked if they made any different temperature ranges and was told no, but I've heard that the TRD was different.

And no, there's nothing wrong with running 200 F, it just pisses me off when something like this changes for no apparent reason. I figure mine ran great at 183 F for nine years now, why change it at this point.

 

[Shadow]

This issue may have to do with the position that the "jiggle valve" is installed in. I installed my jiggle valve at 12 o-clock. Toyota FSM states it should face down, so 6 o-clock. I'm going to try flipping mine this weekend, if time allows and see if it makes a difference.

 

[amocaT]

Thanks for all the response and info

 

[01tundra]

As an experiment, I installed a Stant 170 F t-stat over the weekend and so far it's been running 180-183 F now. It's going to get hot again later this week, then we'll see what the temp runs, but so far it's definitely pointing toward the factory t-stat being a little off on temperature.

The factory t-stat is stamped 82 C (179.6 F) and keeps the engine running at 191-193 F when it's in the 90's outside and with the A/C on it runs about 197 - 200 F.

I'll report back later in the week with my findings.

My FSM says to install the jiggle valve at 12 O'clock, which makes sense since it's purpose it to allow air to bleed through (high point) to avoid trapping it in the system when filling.

INSTALLATION
1. PLACE THERMOSTAT IN WATER INLET HOUSING
(a) Install a new gasket to the thermostat.
(b) Insert the thermostat into the water inlet housing with the
jiggle valve facing straight upward.
HINT:
The jiggle valve may be set within 30° of either side of the prescribed
position.

The Stant doesn't have a jiggle valve.

 

[Shadow]

Over the weekend, I flipped the thermostat in my 2002 3.4L 4runner so the "jiggle valve" was at 6 o-clock instead of 12 o-clock as it had been. The FSM for the 4runner states it should be at 6 o-clock, so maybe it's different from the Tundras?

My temps went from 202-206 (jiggle valve at 12) down to 190-193 (jiggle valve at 6). This is a 180 degree thermostat. I'm happy now I guess.

 

[cruiseroutfit]

Wow, very interesting to hear of such a difference with the jiggle valve. Might have to look into that on my truck as it was last replaced by the dealer during some warranty work.