4mydogs

For reasons previously discussed in another thread, I'm running my 4Runner without a thermostat. It usually isn't a big deal in the south, but with the colder temps we're seeing lately I'm contemplating putting a barrier in front of at least part of the radiator, like truckers do in the winter. I'm thinking it will help the engine get up to operating temperature. Has anyone here even done this with your 4Runner? I'm trying to determine what/where would be the best method and placement.

crolison

I did on my old jeep i used to have. I just put a piece of carboard in the grille.

GorgeRunner

Same here. I lived at 10K feet in the Colorado Rockies and worked at 13K, it was very cold in the winter and I mean really cold; below zero much of the time, usually double digits below.
I stuck a piece of cardboard in front of the radiator of my 54 Willys to get the operating temp up, but when we were bushwacking around the mountains, the snow was over the hood of the Jeep and would cause the flathead 6 to overheat because no air was flowing through the radiator.
I wouldn't do the cardboard thing unless it was really cold, just let your engine warm up before you start driving.

mt_goat

I wouldn't do it without a real (not factory) water temp gauge to monitor. OBDII scan tool readout would work too.

I blocked off 1/2 of my tranny cooler once in freezing weather and it got hot enough that the fan controller kicked on.

toyminator2000

Blocking radiators should only be done on Diesels because the size of their radiators is so massive that the engine will never warm up to operating temp without blocking it. Gas engines are not designed this way and you are risking overheating by blocking the radiator.

Jerry rigging one thing to correct a problem caused by jerry rigging something else is just asking for trouble. Why don't you just fix the thermostat? you can get cheap ones for about $8.00

okie81

"""I blocked off 1/2 of my tranny cooler once in freezing weather and it got hot enough that the fan controller kicked on."""

That poses a good question goat; I used to have a 89 Camry automatic that wouldn't go into overdrive on cold days until it warmed up. I've noticed something simular on my 4runner at times too. Does toyota have a temperature-dependent actuator of some sort that would hold the tranny out of overdrive to rev it up higher and get it warm? If so, how would blocking the tranny cooler effect that?

mt_goat

Yes, there is a coolant temp sensor that keeps the tranny out of OD until it gets warmed up.

Pistonman

Watch the temp and adjust the size of the block off till you sustain the desired temp. That is how I do it.

ozziesironmanoffroad

sure, ive used cardboard in mine when i used to camp up in the mountains in vegas. it would get like 2F, and getting it to warm up was a chore. so i blocked half the radiator, worked great. KEEP AN EYE ON YOUR TEMP GAUGE

annoyingrob

I've been driving around with a piece of cardboard blocking my rad for more than a month now. I also installed a brand new toyota 88c thermostat.

Granted, I also have a turbo rad in the truck.

toyminator2000

Not sure about electronically delaying the shifts but the cold(thicker) fluid definitely affects line pressure which is related to shifting in an automatic tranny. Try using Synthetic ATF.

mt_goat

That really is good advice...if only it were that simple for him, but apparently its not: https://www.yotatech.com/forums/f116...-kaput-148212/

abecedarian

out of curiousity... what are you gonna do when the engine temp starts getting too hot?
run out and remove the 'obstruction', drive 1-2 miles til it cools off, re-insert the 'obstruction'... etc?

I must have alzheimers or something... why no thermostat?

abecedarian

wait... I've got an idea!!!!!
get some custom wooden mini-blinds and put between the grill and rad, then run the slat-tilt rod into the cab.

4mydogs

Yes, that's me, and 7 months later still driving it without the thermostat. It only really becomes an issue if I want to drive the truck far, which I don't do much these days, because if it's too cold out it won't warm up enough to shift into OD. Still get good heat out of the heater.