Operating temperature limit for a 3.4?

[Rwhockey29]

Drove down to austin from Dallas today with a fully loaded 99, lifted with 33's and filled with stuff and 3 people. Did about 75 the entire way. My water temp is usually around 180-184 normally. On the way down I was operating at 190-195, and on the hilly part peaked at 200 for just a second.


At what water temperature should a worry about damage or a blown head gasket?

 

[alumarine]

If that's accurate that's probably where it should be.
I'm at 198 all the time.
OE thermostat is 180-185 I believe.

If you run an antifreeze/water mixture with a proper rad cap boiling point would be around 250-260 ish.

 

[phattyduck]

200*F is absolutely no worry. The temp gauge probably doesn't move off the center until at least 230*F... And damage probably starts somewhere above that.

There are many 4Runners out there with incorrectly installed thermostats that run 200-210*F all the time with no long term damage.

As another data point, my wife's Mini engine runs at 225*F under cruising conditions... and has for ~120k miles just as designed.

-Charlie

 

[aontkos]

>220F seems to be the general consensus around these parts for the 5Z. I generally run 184-190F according to my Scan Gauge...but I've declared 220 as my "pulling over point."

 

[Rwhockey29]

Good to hear thanks guys. I assumed it would be higher, but it's my first trip in the 4runner and just wanted to be sure. I'm running a 50/50 mix of OEM red Toyota coolant and water.

 

[masphx]

Im supercharged and have big lightforce lights right at my grill. I idle at 185 but at speed 70-85 mph i can climb up to 215 and i have touched 222 degrees. If i back off to 65mph i will get back down to 185 pretty quick.

 

[shootmymime]

Im supercharged and have big lightforce lights right at my grill. I idle at 185 but at speed 70-85 mph i can climb up to 215 and i have touched 222 degrees. If i back off to 65mph i will get back down to 185 pretty quick.

Good to hear thanks guys. I assumed it would be higher, but it's my first trip in the 4runner and just wanted to be sure. I'm running a 50/50 mix of OEM red Toyota coolant and water.

>220F seems to be the general consensus around these parts for the 5Z. I generally run 184-190F according to my Scan Gauge...but I've declared 220 as my "pulling over point."

Next time it gets hot (220 ish) keep the peddle mashed. (or whatever your doing. Drop the windows and turn the heat on full blast. i can drop temps just by doing that down to 205 in a matter of seconds. Its amazing how much cooler it gets with that added cooling capacity.

its common being supercharged and pulling a heavy load on a hill at times.

BUT being supercharged you have to remember that this is probably caused my lean conditions and high EGTs. its a good way to burn a piston or valve. I keep and eye on my AFRs. That window drop and high heat is a great way to drop temps without slowing down.

 

[raty4R]

I do kind of what Shootmymime does but I turn on the rear seat heater and leave the windows closed. Works good.
I usuall run 212 in traffic and 203 on the freeway. I'm in DFW so it does get hot outside.