As some of you know i got the 85 4runner. Went to the sierras in it the other day and it overheated. Since then we have replaced the thermostat and clutch fan as well as the radiator cap. Hasnt overheated since then, but i havent hit any stop and go traffic in it since we put all the new parts on it, and it still seems to want to run hot when slowing down (less air moving over engine) ... do you guys have any ideas or anything im missing?

 

Is the radiator in good shape??

 

Is your water pump working efficiantlly? Did you make sure to put the correct temp. T.stat in? Perhaps you did not get all of the air out of the system while replacing the T.stat. Just some thoughts.

 

Yea, somtimes the radiator can get too full of crap and needs to be flushed. Also, is your fluid full and at the corect dilution? These engines normally never overheat.

 

radiator seems to be in decent shape and yes the thermostat is the correct temp not sure bout the water pump though.

Is there an issue with the heater inside the car trapping air which might cause the overheating problem? Cause that things works sometimes and sometimes it doesnt.

 

Mine does the same thing. My heater works well and sometimes it doesn't and it will ocasionally creep up the temperature guage a bit higher than it should. I just bought mine so I'm trying to work all the bugs out as well. I also have an 85 22re.

 

waht tstat did you repalce it with? the 22r and 22re engines are notorious for having a problem called temperature overshoot..... seems eventually all of these 22r/e engines get this problem over time... there was a tsb issued for it way back in 87..... http://www.4crawler.com/4x4/CheapTri...tml#Thermostat

the toyota dual stage thermostat is the best one..... info can be found in the link i posted above

 

this ˟˟˟˟ has straight up overheated though ... im not talkin reading a little higher than nortmal.

 

im telling you tstat, get the dual stage one!

 

Was it blowing steam out? The overshoot issue looks just like overheating. Mine has shot up to the red and held there. Freaked me out, pulled over and it came back down to normal. The system gets small air pockets built up over time, from the heating cooling cycles, that settle behind the t-stat causing it not to open when they are supposed to. The 2 stage takes care of that by opening the smaller valve sooner.

I would suggest having the system flushed, a 2 stage T-stat from the dealer, refilled with Toyota Red coolant, and burped of air. When filling the system fill the motor from the T-stat housing, with the upper heater hose disconnected(this will allow air to excape from the hose), continue filling until the motor is full. Put on the t-sat and fill the radiator. Reconnect the heater hose when coolant starts to come out of it during any of the fill process. Run the engine with the rad cap off until the t-stat opens and top it off.

 

back when I had my 87 22R I drilled a small hole in the flange of the T-stat, took a bit longer to warm up but took care of the air problem...

 

that sounds about right, thanks for the advice pirate.

 

ok folks, my 85 4runner started to overheat today, it did not go all the way in red, but it was a hair away from the red zone. if i drive it on the highway, it cools down a little but not to normal level. the radiator is about a year or two old. dont know what it could be.

 

sounds liek commomn tstat problem

 

jim i knew u were gona say that ill try it out. is it hard to get to the tstat? ive never replaced one.

 

if its got a 22r its uber easy... right in the front just behind where the fuel pump mounts on a carbed truck....

 

its a 22re. i have no clue where the fuel pump mounts .... any pics?

 

its on the right side of the engine... find your upper radiator hose... its the part connected to it that isnt hte radiator

 

ok, kool, ill look at it tomorrow morning, is it easy to take off? its right next to the hose that attaches to the engine?

 

i am running a rear radiator with my re and found i was having some over heating issues from cavatation of air in the water pump. i drilled 4 1/4 holes in the tsat and havent had a single problem sence. these motors are bomb proof and overheating is usually not an issue. i would start with tsat as many have said.