Keeping it cool while at low speed!

[gaz]

JMF,

One thing is for certain, if your not running as cool as usual, something is probably up.

There have been a few really good suggestions to correct your temps:

-an engine oil cooler is a very economic, sound method to reduce both engine and under hood temps
-deleting the crankshaft fan/clutch for an electric setup will free up some power stolen to spin that HEAVY crank clutch/fan setup. I have found, even while in Arizona/S. California in the heat of Summer that I didn't need any fan unless at a stop light or driving under 35 mpg (the only times my electric fan ever needed to be on). Additionally, of all my efforts to improve fuel economy, no single other change has caused a greater improvement in fuel economy than taking off that crankshaft driven fan/clutch.

I have a truobleshooting suggestion which usually shows me what's really wrong with cooling issues and it's almost free. Install a new radiator cap, remove the thermostat and carry 2 jugs of water until you know what's up. If there is a problem with your cooling system, without a Tstat, it should reveal itself inside 2 weeks normal driving.

The problems this method has revieled to me are:

-leaking heater core
-leaking radiator cap
-bad or slow opening Tstat
-dead water pump
-leaking water hose
-leaking radiator
-compromised engine head gasket
-compromised engine head

One additional benifit to briefly operating your vehicle this way, in that environment is that you will see what temp it runs at with FULL COOLING POTENTIAL, at all times. It will run a little cool or at least it should. If you happen to be losing coolant slowly, this will speed it up so that you can see.

 

[JMF661]

I appreciate the input folks. I've done a lot of these things; water pump, oem thermostat, flushed system thoroughly and check coolant level for leaks routinely.

I've had this radiator out of the truck, i dont recall how easily it drained though. It may be worth pulling out and looking at while I have the fan clutch out for replacement.

 

[Eddo Rogue]

Rock auto has a good selection of various thickness radiators. That's where I got my single core from, and it worked out great!

 

[Uncle Gump]

JMF,

One thing is for certain, if your not running as cool as usual, something is probably up.

There have been a few really good suggestions to correct your temps:

I have a truobleshooting suggestion which usually shows me what's really wrong with cooling issues and it's almost free. Install a new radiator cap, remove the thermostat and carry 2 jugs of water until you know what's up. If there is a problem with your cooling system, without a Tstat, it should reveal itself inside 2 weeks normal driving.

The problems this method has revieled to me are:

-leaking heater core
-leaking radiator cap
-bad or slow opening Tstat
-dead water pump
-leaking water hose
-leaking radiator
-compromised engine head gasket
-compromised engine head

One additional benifit to briefly operating your vehicle this way, in that environment is that you will see what temp it runs at with FULL COOLING POTENTIAL, at all times. It will run a little cool or at least it should. If you happen to be losing coolant slowly, this will speed it up so that you can see.

Gaz... I'm sorry... but there are so many things wrong with this... I don't even know where to start.

Running an engine without a thermostat is just a totally bad idea. The only thing removing it could possibly diagnose would be a stuck thermostat. Anything else you mention could certainly be found with a thermostat in place.

The thermostat is there to aid the engine to reach operating temperature quickly. Probably more important... it provides a restriction to coolant flow. This restriction allows the coolant the time it takes to absorb the heat being transferred by slowing the flow through the engine. Without this restriction... the coolant flows through the engine to fast to absorb the heat and carry it away to the radiator.

I've built engines with no plan to ever use a thermostat... but rather a restrictor plate. With the restriction... you simply won't get the heat transfer.

 

[cbxer55]

I view the change of the thermostat as the choice if nothing else works. I did the thermostat thing some years ago and it worked great in the summer but winter time was no fun. Of course, the OP lives in California, so winter isn't that much of a concern.

I live in Oklahoma and have never had a problem with winters. Truck still gets hot, a 180 is still frikking hot. So is a 170.

 

[Shran]

Regarding factory gauges: I can tell you from experience that there is a large amount of variation in factory gauges between trucks, even of the same year. First gens were awful. Second gens were better, still not accurate, but at least there is visible movement. For example:

My '92 Explorer normally reads just to the left side of the middle - around the R on noRmal. I can tell when the thermostat opens because it'll creep just past that and then dip back down to O. If I let it idle with the AC on during a hot day, it'll creep over towards M and when it gets past M, the idle speed will kick up a bit to move more air through... I did not know '92 was sophisticated enough to do that until it happened.

My stepside truck that has a '92 engine and dash will stay between R and M at operating temp. The thermostat opens when the needle gets past M, then it dips back to O and back up... the needle's sweep is MUCH more dramatic than other 2nd gens I've had. 195 degrees on that gauge would probably be something like 220 or more in my Explorer.

 

[franklin2]

A radiator guy told me how to check and see if my radiator is clogged.

1. Drain the radiator of coolant.

2. Take the lower radiator hose off.

3. You may need another person to help, but take the palm of your hand and seal off the large bottom port where the lower hose goes on.

4. While blocking the lower outlet with your hand, pour water into the radiator till it's completely full.

5. Once full, quickly pull your hand off the lower outlet.

If the water comes out smooth, full force filling the complete pipe up as it comes out, the radiator is good. If it comes out partial flow, and may even gurgle or gulp some, the radiator is partially clogged.

 

[cbxer55]

Regarding factory gauges: I can tell you from experience that there is a large amount of variation in factory gauges between trucks, even of the same year. First gens were awful. Second gens were better, still not accurate, but at least there is visible movement. For example:

My '92 Explorer normally reads just to the left side of the middle - around the R on noRmal. I can tell when the thermostat opens because it'll creep just past that and then dip back down to O. If I let it idle with the AC on during a hot day, it'll creep over towards M and when it gets past M, the idle speed will kick up a bit to move more air through... I did not know '92 was sophisticated enough to do that until it happened.

My stepside truck that has a '92 engine and dash will stay between R and M at operating temp. The thermostat opens when the needle gets past M, then it dips back to O and back up... the needle's sweep is MUCH more dramatic than other 2nd gens I've had. 195 degrees on that gauge would probably be something like 220 or more in my Explorer.

On all three of my Fords, the needle is sensitive enough I can tell when the thermostat opens. They all go up and at a certain point, drop back down slightly. Therefore, when I change the t-stat, and the needle goes from pointing dead center to pointing at the one third point, I know it made a difference. 195 stat, points dead center. 180, points 1/3. 160 it pointed at 1/4. I ran that one summer only and it was fine. But in the winter, got the code saying temperature wasn't warm enough to make the switch from open loop to closed loop. Took it back out and put the 180 in.