Is my fj62 overheating? You tell me!!!

[chitown40]

This should not be this complicated.

Put the thermostat back in after to verify it is working correctly, or else install a new Toyota OEM one -- they are inexpensive.

If your temps are climbing up while in traffic or stopped, then you have a potential problem with your fan clutch. If it's original, just replace it and be done with it.

If the radiator was replaced with a new one and you have no other evidence of a blockage, cracked block, cracked head, bad head gasket, etc. then you've just narrowed your problem right to the fan clutch.

Hope this helps.

R

 

[FJ-KroozerKrusader]

hey guys, i am a mechanic in training at my school and so i asked my instructor about it soo we checked out my fan clutch and it has good resistance and is engaging, i showed him where it registering on my gauge and he said that is fine, he said it would be bad if stayed around the red. i dont want to throw parts at something that works fine and how its suppost to. my rad works great , no leaks, no bad head gasket, burped and all. the only thing i may do to make myself feel better is put a lower temp Tstat just to see. when i do that i will update ya'll but right now i have my evap core torn apart to replace my a/c expansion valve, by the way autozone's doesnt fit and no one else has it soo dealership baby, good thing i have a friend at the toyota dealership. thanks again fellas and God Bless- Cody

 

[John McVicker]

You likely do not have a problem, you are way over thinking this. Stock gauges are nortious liars. My suggestion would be :

1) Keep/put the correct T-stat that the Toyota enginers designed for the truck.

2) Install a good after market temp gauge.

3) Address whatever issues this shows.

Again, most likely you have none, but this way you won't be guessing and you will be set for the long term.

John

 

[Randy]

hey guys, i am a mechanic in training at my school and so i asked my instructor about it soo we checked out my fan clutch and it has good resistance and is engaging, i showed him where it registering on my gauge and he said that is fine, he said it would be bad if stayed around the red. i dont want to throw parts at something that works fine and how its suppost to. my rad works great , no leaks, no bad head gasket, burped and all. the only thing i may do to make myself feel better is put a lower temp Tstat just to see. when i do that i will update ya'll but right now i have my evap core torn apart to replace my a/c expansion valve, by the way autozone's doesnt fit and no one else has it soo dealership baby, good thing i have a friend at the toyota dealership. thanks again fellas and God Bless- Cody

If the temp gauge is showing hotter than its ever ran before, you have a problem. It may not be major problem, but still a problem. If something starts doing something its never done before, that's your cue to that somethings up with your rig. Verify with a manual temp gauge or an I.R. gun to verify its running hotter than the thermostat operating temp setting.

 

[Elbert]

Save yourself some money...install an aftermarket mechanical guage from autometer or someone else...then you will know if the truck is running hot or not. If you exceed 210-220 its time to understand why.

The thermosat + gasket + O ring are easy to change...if you go to the trouble of taking the water neck apart....its worth your time and money to install new parts.

FYI.... would it be better to know factually what temp the truck engne is running ...rather than having to guess with a "hot vs. cold " OEM guage?

 

[Bryan062087]

I had/have the same problem as he does. I installed a mechanical water temp gauge. Factory gauge was 100 percent accurate and corresponded to the mechanical gauge. Just saying..

 

[bullprick]

Mine has exact same symptoms. Hot days, red lights, stop n go traffic runs at point shown in your picture. All other times it runs dead center where it should on the temp gauge. The question is are you having to replace coolant in your overflow resevoir. Mine is my daily driver and I have to replace coolant from below the low level about 3 times every 2 weeks, but my needle never goes past the point referenced in your picture??? ............myself dumbfounded as well

PS, I live in Dallas Texas and in the winter and cooler weathered months, I never have to replace coolant

 

[worshhim]

When I first got my FJ62 the temp sat faithfully at 1/4 and then after a couple years began to run hotter. I replaced all cooling components over a period of a year or so and still had some trouble with running hot. When my tranny finally quit, I replaced it and added a tranny cooler. Since adding the tranny cooler, temp sits comfortably at 1/4 once again.

 

[bullprick]

Yeah i have a tranny cooler too, my problem might be the cooling fan clutch. Is the fan (located driver side fender) supposed to come on during engine operation, or only after the truck is off?

 

[Jan-78FJ40]

Yeah i have a tranny cooler too, my problem might be the cooling fan clutch. Is the fan (located driver side fender) supposed to come on during engine operation, or only after the truck is off?

You are probably talking about the carb cooling fan. it looks like a hair drier and points at the carb. it has nothing to do with the engine coolant.

The fan clutch sits in front of the engine on the waterpump. it has oil in it that becomes more viscous with heat, then locks up the clutch and gets it to turn with engine speed. It is important when going slow or standing in traffic, when no air is pushed through the rad by driving.
When the temp climbs at slow speeds or when in traffic, the fan clutch is likely the culprit.
J

 

[Jan-78FJ40]

Your truck is probably about at 220-225 degrees in that pic.. too hot. Yes you are overheating, but not so hot that you need to shut it down right away. If you figure out your problem let me know, mine's been doing this for years in stop and go traffic and I cant figure it out.

However you want to phrase it, his engine is running too hot according to that temp gauge. 220-225 is not the range in which you want the engine to operate, although you are right there is not imminent danger per say.

I've heard its bad to remove the thermostat completely as well.

Did it do this before you changed the radiator?

Make sure you got all the air out of the system and make sure your fan clutch is working well.

That is plain wrong information. From that pic you can neither deduce the real temperature, nor is there any indication of overheating there. The stock gauge (as has been mentioned here) is inherently inaccurate. 3 stock gauges at the same temp will leave the needle in 3 different positions. The only way to accurately measure the temp is with a good aftermarket gauge.
j

 

[Jan-78FJ40]

Mine has exact same symptoms. Hot days, red lights, stop n go traffic runs at point shown in your picture. All other times it runs dead center where it should on the temp gauge. The question is are you having to replace coolant in your overflow resevoir. Mine is my daily driver and I have to replace coolant from below the low level about 3 times every 2 weeks, but my needle never goes past the point referenced in your picture??? ............myself dumbfounded as well

PS, I live in Dallas Texas and in the winter and cooler weathered months, I never have to replace coolant

You are having a leak somewhere. The coolant system is a closed system, so you should not loses coolant (except the miniscule amount that could evaporate from the overflow reservoir, which is MUCH less that what you are losing).
Pressurize the system, and you will certainly find it leaking somewhere.
cheers,
J

 

[Jan-78FJ40]

Oh, and finally, taking out the thermostat is a bad idea. Your engine oil has optimal lubricating features above 180 F. The thermostat keeps the coolant in the radiator from circulating through the block when you start up, and therefore allows the block to heat up to optimal temp faster. If you ditch it you might run cooler, but if you constantly run below 180 that is really bad for the engine too.
cheers,
J

 

[Aseif007]

Not sure if it has been mentioned but what condition is the radiator cap in?

 

[FJ60Croozer]

You are having a leak somewhere. The coolant system is a closed system, so you should not loses coolant (except the miniscule amount that could evaporate from the overflow reservoir, which is MUCH less that what you are losing).
Pressurize the system, and you will certainly find it leaking somewhere.
cheers,
J

I agree with pressure testing the cooling system. I had a couple of little hoses that went to the heater that were leaking on my FJ60. All better now.

 

[satchel]

I have lost coolant out of my radiator because the cap was bad and allowing it to go to the overflow and spill out, and later it would suck it back in so there wasn't ever a lot in the overflow. The cap simply couldn't hold the system to 13psi, almost right off the bat when the truck started without really any warm up it would start sending it out to the overflow. You may want to check that, but you would likely see remnants of coolant coming out of your overflow while you drove it if that is the case.

 

[hjdca]

My FJ62 never goes past the 1/4 mark on the gauge even with the air conditioning on in 100 degree weather, in traffic. My clutch fan works very well though. I can hear the clutch fan kick on and move air like a tornado when it is hot. It robs power from the truck and really makes alot of air noise. Then, when it kicks off you can also really tell. The air noise quiets down and you get more power from the truck. If you are not really noticing this, it is really very obvious, I would suspect the clutch fan.

 

[hadinoman]

Problem

I had the same problem. On long drive, the gauge used to be on 1/4 but on local slow driving it used to go till the middle or at times slightly above it especially when the AC (air condition) is on.

Solution

Last week, with the suggestion of a friend i fixed two electric fans in front of the AC condenser for better throw of air into the radiator. One fan is 8" of size and the second is of 10". These fans start when the AC is switched on and stops when it trips or u put it off.

Result

After driving the cruiser for the last one week, the result was as follows.
1. On local, with AC, the temp gauge is not going above 40% of the limit.
2. On long drive, with AC, ie on at constant speed of 120 KM/hr, the temp gauge was on 55% ot 60%.

Now this is strange. Can someone please put me wise as why this change?

 

[Von Hayek]

That is plain wrong information. From that pic you can neither deduce the real temperature, nor is there any indication of overheating there. The stock gauge (as has been mentioned here) is inherently inaccurate. 3 stock gauges at the same temp will leave the needle in 3 different positions. The only way to accurately measure the temp is with a good aftermarket gauge.
j

I think this advice is dead on. As I am experiencing some cooling problems myself, I've been juggling these issues. An easier solution than an aftermarket gauge is to by a hand held infrared thermometer. Get your truck up to operating temperature and shoot the thermostat housing or the radiator and see what temps you get.

Coincidentally, my gauge registers where your does when I come to a stop and that translates to about 195-200 degrees on my truck. The factory service manual calls for the thermostat to open in the 187-194 range. Pretty normal.

My guess is that your fine. Shoot it with a thermometer to find out.

 

[FJ-KroozerKrusader]

well guys, today i fixed my AC and it was running perfectly, i mean ice cold after the expansion valve and evap was cleaned and put back in to be charged. drove it to a friends and parked it, all is good. started it up to back out to go home and i noticed a poof of white smoke, my heart sank!!! drove home and parked it and started it again after a little while and white smoke again(poof). engine bay was very hot all over. i tore open the thermo housing and it was pretty built up in there with gunk. i ordered a new one with the gasket. but the white smoke.............i checked my oil and it is lower than it has ever been but it doesnt seem like it had coolant in it. is my head gasket gone ya think? and do you always have to machine the head when it is off to do the head gasket? God BLess -Cody