how hot is too hot?
 

Those of you who have installed a real aftermarket water temp gauge in your 22re, how hot have you seen it get? How hot before it's time to seriously worry?

ive seen them run at 250 Fahrenheit for a while with out any "immediate" problems.

i let off the throttle at about 215 Fahrenheit.

anything warmer than that is a gamble imo.

I once saw a show on ABC Primetime about Nascar racing and I caught some of the teams talking about over-heating in the pack from lack of air flow to the grill. I thought it was interesting one driver was asking the crew how hot is too hot on the water temp. He said he was running 250 degrees F. The answer came back that 280 was a blow up, 245 was too hot for power, and 235 was good. I believe those teams run the Evan's waterless coolant but I could be wrong on that.

Personally I start to worry around 220F, but I run Evans waterless coolant (no chance of boiling that stuff lol).

Good to know. What amazes me after installing the aftermarket gauge is how the stock one operates. I've seend temps from 160-210 and the stock gauge registers in the same spot regardless of where within that range I am.

where did you tap the sender for the aftermarket one??

I used LC Engineering's manifold that goes in the top radiator hose.

theirs a royal purple radiator additive that works realy well but ive never gone to 220 i put that aditive stuff in a my radiator went down ten degrees instanly its worth a shot if stuff starts over heating :welder:

There is also this stuff http://www.redlineoil.com/Products.aspx?pcid=10

Interested to see how well this stuff works

Ive got a VDO water temp gauge that takes a reading from the intake manifold in the middle behind the thermostat.

At start up obviously is show 0 but during the first heat cycle it will climb to about 215 and then down to about 170.

After that it continually cycles from 185 to 200 in normal driving conditions.

On the freeway at night or cooler temperatures (in So Calif.) it will stay at a constant 185-190 without cycling, if you get off the freeway and go back to city driving it will resume its 185-200 cycle.


I LOVE having this gauge as like mentioned above my stock one does not move at all!

I'm going to jump in here and selfishly link to my post about wiring up some new autometer gauges (and fixing a coolant leak....and then experiencing a strange cooling system issue...).

My questions have gone unanswered the last couple weeks and I'm curious about the right next steps.

Here's the thread:
https://www.yotatech.com/forums/f131...05/index2.html

Like others who have installed an aftermarket gauge, I was excited to see the ACTUAL temperature cycles of my coolant system....but also a little shocked at how the OEM gauge would peg in the "middle" of the gauge, despite the engine being all over the place in terms of heat.... To preface my thread, I went from 180 in city driving, to quickly 230 on the freeway....the whole time my OEM gauge happily sat in the middle, indicating "normal"...scary.

Anyway, if any of you guys know coolant systems better than me, I'd really appreciate if you could take a look at my thread and add any wisdom. I personally think my TSTAT may be on the fritz, but am open to ideas from those who know (a hell of a lot) more than me :)

/end hijack

Yeah it will start to move off the middle "normal" at around 235-240 F, its really just a fancy idiot light. Once it shows hot its too late. :con:

Basically what ever temp you start to boil your coolant on the head surface is too hot because once you boil coolant you're dead.

Pressure in the system and coolant/water % are the biggest variables with that boiling point. A good rad cap, a sealed leak free system and at least 50% antifreeze with the water are cheap ways to raise the boiling pt.

when i put my gauges in it was wierd to see the temp fluxtuate the way it does, but i got used to it and now i dont think i would go back to stock. im with mt goat once u see a big change its too late!!!

I put a temp gauge in the tstat housing, so it is effectively the same as the top radiator hose. I have my fan set to kick on around 210F. However, the sensor for the fan is affected by air convection, so it kicks on at 210F on the highway and closer to 200-205F in the city (airflow wicks heat away on the highway, making it read cooler).

On grades on the highway, running 3k rpm and more than half throtte, it can outrun the fan and creep up to 215. On a warmish day the fan will often run nearly continuously if I'm driving over 65mph.

Interesting to hear that you guys are getting well into the 230's without any problems. The factory tstat is 195, right?

180 F with the V6s.

i just bought a toyota oem t-stat to put in my freshly rebuilt 22r. i was curious as to the temp because autozone and oreillys both told me my factory temp was 180. wrong! i knew it was more then that. stamped on the toyota t-stat was 88C which is 190.4F. my 87 autometer gauge (full sweep mechanical) climbs to 190-195 upon warm up and stays there. mostly city some highway but i have yet to see it above 195. might be a little higher this summer.