While driving the kids to school yesterday I noticed that my heater was not blowing hot air. I took a look at my temp gauge and it was in the red. Does this mean my thermostat has had it? Any ideas and thanks in advance.
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Pop the hood and check the coolant level. Listen for gurgling/boiling noises. Check all belts and hoses. Look for leaks.
While driving the kids to school yesterday I noticed that my heater was not blowing hot air. I took a look at my temp gauge and it was in the red. Does this mean my thermostat has had it? Any ideas and thanks in advance.
Yes. I'm 99% sure your thermostat failed.
Changing just the thermostat isn't hard - but you will likely drop most of your coolant to do it. Be sure to orient the jiggle valve properly.
Why are you so sure of that?
No in cabin heat is a symptom of severe overheating, regardless of the cause of the overheating. (For example: Blown headgasket, blown water pump, busted water pump belt, etc...).
I'm not saying it's NOT the t-stat, but there are plenty of variables to consider when dealing with acute overheating.
On a 91-92:
Very easy to get at the t-stat, without losing much coolant at all.
No jiggle valve issue as the t-stat does not sit "sideways" as on a 93-97.
There *is* an o-ring issue: Make sure you get the o-ring that sits on top of the t-stat, and install it carefully.
Hmm... wouldn't no heat in the cabin also be a sign of,.. Air in coolant system,.. stuck or broken temp diverter door... (or whatever they call it in the Toyota)... the temp knob becoming disconnected... I can't see it being only a sign of "severe overheating".
Why is it always worst-case scenario? Especially when we don't have clarification/complete description of the issue?
Nonsensical.
I took a look at my temp gauge and it was in the red.
On a 91-92: There *is* an o-ring issue: Make sure you get the o-ring that sits on top of the t-stat, and install it carefully.
You sound amazingly calm for someone who just ran their engine temp's into the red. You'll be very lucky if all you need at this point is a new t-stat. (Plus that's not likely the issue.)
So what did you do? Pull over immediately? Pop the hood and check the coolant level? Listen for gurgling/boiling noises? Check all belts and hoses? Look for leaks? Or...?
Yes. I'm 99% sure your thermostat failed. Get an OEM one - even if you have to wait a day or two for it to come in. The parts store thermostats are junk by comparison.
It is a relatively easy job - but gets more involved when you start looking at the WYIT (While you're in there) aspects of it. With the coolant out - its probably a good time to replace all the rubber coolant hoses. Since you're replacing hoses, may as well do belts, right?
Oh, and you wouldn't want to do all of this and leave any sediment or old coolant in the system - so a multiple flush is in order. Be sure to disconnect and flush both front and rear heater cores from the firewall - and get the soft lines up underneath.
Now that you have a pristine clean system, you wouldn't want to put just any coolant in so you'll want to $28/gallon Toyota special coolant - two gallons of it. Oh, and distilled water to mix with it.
But, yes, it sounds like your thermostat failed. I'm assuming the system was full of coolant before it failed - if not, it could be very bad. Changing just the thermostat isn't hard - but you will likely drop most of your coolant to do it. Be sure to orient the jiggle valve properly.
Were you boiling water and steam out of the radiator cap? If not, I wouldn't worry about it - if the engine is hot enough to do damage and had coolant in it, the radiator cap would be screaming like a kettle in a bonfire.
IMHO YMMV I'm not a mechanic.
Keep us posted please: We haven't seen many t-stat failures in the closed position that I can recall. Hopefully that's all it is.
You sound amazingly calm for someone who just ran their engine temp's into the red. You'll be very lucky if all you need at this point is a new t-stat. (Plus that's not likely the issue.)
So what did you do? Pull over immediately? Pop the hood and check the coolant level? Listen for gurgling/boiling noises? Check all belts and hoses? Look for leaks? Or...?
Well ****. Now I'm the one who get's to hope it's just the T-stat.
Driving in town after about 10 miles on the freeway, ~24* ambient temp.(!), started to overheat. Shut 'er down *really* quick; never lost heat in the cabin, gauge never made it into to the red. Belts & hoses fine, no leaks, coolant in both rad. and overflow was full but *was* boiling into/out of the overflow. After cooldown, radiator full and still some coolant in the overflow. Haven't re-started it since; got a ride home on a flat-bed and will check it out in the next couple days.
Curtis