Still having cooling issues...

[Ihasfip]

So, even after following the FAQ and flushing my system for like 3 hours and refilling with green (non long life) antifreeze, installing a Landtank fan clutch my truck still runs hot. I have my temp gauge mounted in the block drain and it will read around 200-205 after idling for 20 minutes on a 75 degree sunny day. Runs around 210 on the highway at 70, with the a/c on. Whats the deal? Is my cheapo Equus gauge not accurate or what? I don't want to risk blowing this thing up, but I am gettin worried. What else is there to check? When I flushed it the only thing that came out was clean Toyota red antifreeze. No gunk. NONE. Both heaters work great. Even with my 2 electric fans on it only goes down to about 195 at idle. Unaffected at highway speeds.

D

 

[john_eckels]

Did you change the thermostat? Mine was sticking and causing it to run a bit hot.

 

[Michael Hanson]

Thermostat,air in lines,are you getting heat out off your heater? Mike

 

[Ihasfip]

Never changed the thermostat. Because it doesn't over heat. It just doesn't run as cool as everyone elses. I guess I can try that. And no I don't think there is air in the system. And yes, both heaters blow very hot.

D

 

[Brian894X4]

Assuming the reading is accurate and is comparable to other readings such as the scangauge on a 1995 and newer rig, it's about 20-25 degrees hotter than a rig with a perfectly good operating cooling system.

If your radiator is original, I'd wager that it's sludged up and isn't cooling up to full capacity. Common problem.

 

[Ihasfip]

Well I can't say for not whether it is original but it looks to be in very good shape. And like I said upon flushing it, no sludge, or anything for that matter came out.

D

 

[GreenGoblin]

Any temp changes from one side of the radiator to the other?

 

[Ihasfip]

I will check.

 

[Brian894X4]

Well I can't say for not whether it is original but it looks to be in very good shape. And like I said upon flushing it, no sludge, or anything for that matter came out.

D

Sludge isn't going to come out when you flush it. The only way you're going to see is if you pull the plastic caps off and I don't recommend doing that. What you're most likely to find is the grey sludge blocking at least some of the radiator.

Since I've owned the truck, Toyota has flushed out the system 3 or 4 times. Largely because of a mistake where they put the wrong coolent in and I made them fix it. I've also flushed it myself several times. I later pulled my radiator and had it professionally flushed by a radiator shop and none of this flushing did much to the sludge. It was only after I took off the plastic caps that I saw how bad it was. In my case, it wasn't extreme, but enough to affect cooling somewhat.

Here's a picture of one part of the radiator with the plastic cap off. You can clearly see that some of the radiator looks perfectly fine, which is misleading, then there's where a good chunk of it is totally blocked by the sludge. Bear in mind, this is "after" multiple flushings by various people. And...the rig only had about 100K miles on it and was only 13 years old at the time.

http://www.brian894x4.com/images/FZJ80coolingprojectx003.jpg

So right there, about 1/4 of the radiator was rendered useless and I didn't even show pictures of the sludge that had collected on the other side and on the bottom.

Another way to tell is to take a really, really good look inside your radiator cap. It tends to collect in a low pressure area on top of the fins to the left of the cap as you're looking at the radiator from the front. If it's bad enough, you should see it collecting there. You could also reach inside the cap and brush something around in that low pressure area to see if you pick anything up.

If all else fails, this is where I'd start looking. I personally think this is more common that people realize, but as for the cause, that's a long standing debate on here. This has been seen on rigs that get regular maintenance and used only Toyota red coolent. In my case, I know the POs didn't likely maintain the coolent very well and appear to have used green coolent since the early days.

 

[Ihasfip]

So what did you do to remedy this? Replace the radiator?

D

 

[Ebag333]

That, or have it rodded and the tanks replaced (upper and lower).

Many prefer a new radiator. I would price both.

 

[S.CarolinaFZJ80]

Sludge isn't going to come out when you flush it. The only way you're going to see is if you pull the plastic caps off and I don't recommend doing that. What you're most likely to find is the grey sludge blocking at least some of the radiator.

Since I've owned the truck, Toyota has flushed out the system 3 or 4 times. Largely because of a mistake where they put the wrong coolent in and I made them fix it. I've also flushed it myself several times. I later pulled my radiator and had it professionally flushed by a radiator shop and none of this flushing did much to the sludge. It was only after I took off the plastic caps that I saw how bad it was. In my case, it wasn't extreme, but enough to affect cooling somewhat.

Here's a picture of one part of the radiator with the plastic cap off. You can clearly see that some of the radiator looks perfectly fine, which is misleading, then there's where a good chunk of it is totally blocked by the sludge. Bear in mind, this is "after" multiple flushings by various people. And...the rig only had about 100K miles on it and was only 13 years old at the time.

http://www.brian894x4.com/images/FZJ80coolingprojectx003.jpg

So right there, about 1/4 of the radiator was rendered useless and I didn't even show pictures of the sludge that had collected on the other side and on the bottom.

Another way to tell is to take a really, really good look inside your radiator cap. It tends to collect in a low pressure area on top of the fins to the left of the cap as you're looking at the radiator from the front. If it's bad enough, you should see it collecting there. You could also reach inside the cap and brush something around in that low pressure area to see if you pick anything up.

If all else fails, this is where I'd start looking. I personally think this is more common that people realize, but as for the cause, that's a long standing debate on here. This has been seen on rigs that get regular maintenance and used only Toyota red coolent. In my case, I know the POs didn't likely maintain the coolent very well and appear to have used green coolent since the early days.

"The only way you're going to see is if you pull the plastic caps off and I don't recommend doing that."

Were you not able to get the plastic caps back on?

 

[Brian894X4]

I replaced the radiator. It was not worth rodding out to me. Having a shop rod it out and reseal the plastic caps, "might" work, but for my purposes, I wanted a 100% reliable set up, so I opted for the very expensive option of replacing the radiator with a brand new OEM unit from C-dan.

The reason I don't recommend removing the plastic caps is that you have to reseal the caps with new gaskets and then reset the metal tabs and being as it's a pressure system probably have it pressure tested. I only removed my caps after I was sure the radiator was going to be replaced.

I'm guessing this is your problem, but before you go blowing money on a new radiator at least poke around inside and see if there's sludge in the places I suggested and replace the radiator as the last ditch option. I'd hate for you to have a new radiator and not solve your problem.

 

[Ihasfip]

Ok so here I am again. Same issue. I went ahead and replaced the radiator. I put a brass 3 core, with metal tanks in to replace it. 240$ shipped from 1-800-RADIATOR. Next day delievery. Very please. Anyways, after installing it I went back and pryed the tanks off of the old radiator. It was spotless. ABSOLUTELY spotless. I was dissapointed that I replaced it for no reason. And then ruined it by prying it apart. So it was about 25 degrees outside, and after driving it down the road I was back to 210. Idle was about 200. I am getting frustrated. The only thing left is the thermostat. I guess it wouldn't hurt to change it, but like I said it never really OVERHEATS, just seems to run hotter than others. I am also wondering if my s***ty Equus temperature gauge is not accurate. We took a infrared thermometer than and the outside of the radiator was only about 160, the coolant with the cap off was about 170ish, and various parts of the block were on about 180, this was while my temperature gauge was reading 200-205 at idle in the shop. It was approx. 45 degrees in the shop. Any ideas? Or my next step?

D

 

[Dave 2000]

Just a note, it is worth remembering that if your timing or mixture is off a few degrees this can contribute to hot running. I am unsure ot the model you have so cannot add more, is it diesel/petrol ect.

regards

Dave

 

[Ihasfip]

It is gas. And I wouldn't imagine the timing being off as the previous owner never did anything with it except drive it daily, and take it to the dealer for maintenance. I have never messed with it either. He never had it offroad.

D

 

[HomersCanyonero]

Here's a link to an article "5 Steps to a Cooler Running Engine" by Rick Webster.

In your case, it's too bad that you went through all this trouble and it looks like your temp gauge is not accurate. Moral of the story is calibrate your gauge to make sure its accurate.

Also, your strategy should have been to replace the cheaper components first like the thermostat, radiator cap, and coolant.

I replaced my radiator about 4 years ago, coolant is 10k miles old, and I have new water hoses all around. Today my coolant temp was 186 degrees after being on the freeway for about 30 minutes (cold winter for LA -- in the low 60s during the day). Temperature measured compliments of my ScanGaugeII. Oh, original head gasket at 175k miles.

If your gauge is correct and the t-stat makes no difference, I don't know what else you can try. Water pump not pumping?

 

[FirstToy]

Ever consider the possibility that there is nothing wrong with it?

 

[motorsargeT]

I think that there is nothing wrong. You can not compare your readings to anyone elses because your temp sensor is not in the same spot. There are hot and cool spots as coolant flows throughout the system and I'll bet that the coolant drain plug area is a warm spot in the coolant flow. The factory location reading is the only one you can really compare readings from.

 

[jlg32281]

I see that you are a fellow Texan. Here in TX, you don't need anti-freeze to keep you from freezing, you just need the lubricants and anti-corrosives in it. Drop your anti-freeze to 10% and add some water wetter. I think you will see about a 10 degree drop. 10% anti-freeze will give you some of the lube and stuff and water wetter will give you the rest. In the Supra world where over heating is the standard, this is the only way a lot of them will run right. Water is the best dicipator of heat, the less anti-freeze, the cooler you run. I personally had my Supra with zero anti-freeze, just purified water and water wetter for lube and stuff. I currently have my Cobra setup with 10%. This is all just an opinion, but I'm a believer. It rarely freezes here and I park in the garage, the temps in my garage will never dip below freezing. Also, it actually has to be well into the 20's for a car to start freezing and it just doesn't happen much here.