I have an 84 with the carb. 22r. I recently have done a radiator flucsh, as well as new thermostat. After doing so i let her run in the driveway for about 30 minutes at idle. Everything was fine. I have taken her on 5 short 3 miles drives soo far and 2/5 times her heat guage has shot up to the edge of the top white line just before the red. it never gets into the red but it sits just below it. One time it cooled off about a mile from home and returned to normal. the other time she ran hot till i got home. Again the last white line but never in the red. The auto parts store gave me a 195 thermostat. Is that correct? i thought it should be lower.

 

Did u burp the system

 

no sir i did not, could you please explain.

 

How I burp: get the radiator cap as high as you can, remove cap, turn heater to hot with fan on high, start engine and warm up. As the thermostat opens, be ready to put more coolant in as the bubbles purge out.

 

place radiator at high point < park faceing up hill, on a curb on ramps > remove rad. cap, start engine and let run. when fluid starts to come out, put cap on.

 

The Toyota OE thermostat is 190f, not 195f.

T-stat info from 4Crawler

 

Per factory specs, the OEM thermostat begins to open at 190 degrees F and fully opens at 212 degrees F.

edit to add: I should state that my Napa thermostat behaves notheing like the OEM one. Judging by my mechanical temperature gauge, it seams to open much ealier than the 190F and maybe fully opens at the 190F mark.

 

im going to go ahead and try that. What i still dont understand is why when i swithced the thermostat it worked fine. Then just 10 minutes ago on a trip to wendys the temperature shot up to the near edge of the white and stayed there. Also when i shut the truck off i popped the hood, and noticed the the upper radiator hose felt like a rock!...any suggestions?

 

That's what will happen if there is air in the system

 

ok everyone this is what i did:

1) parked at angle
2) filled radiator with about 10 more oz of fluid
3) started vehicle
4) turned heat onto high
5) filled radiator with about 1/3 gallon of fluid
6) let stand for 10 minutes with heat on a filled as need (very small amount)

End result:

1) mild heat
2) temp just baaarely rose in over 10 minutes @ idle and a 2 mile trip around the block

I did buy a fail safe thermostat i guessing it failed open caause of the cold water shock????

 

Drive it for a day and see what happens. And, consider buying a Toyota OE thermostat from the dealer.

 

Its been two days now. End result it my thermo has failed open. But good news is she wont run reach oporating temp. Is that a problem