overheating/ AC turning off

[Taz]

The problem is back! My AC keeps turning off. First a little history

-TRD SC installed
engine getting hot going up hills and AC would turn off
-Intsalled Ron Davis Aluminum Radiator
Engine not overheating
AC turning off at idle when air temp 80+
AC turning off going up hills when air temp 90+F

It seems my compressor is getting too hot?
What should I try next?

 

[LandCruiserPhil]

Are you sure that the coolant temp sensor for the AC is good?

 

[kfarea]

Check fan fuse in the fuse box . i think your car A/C fan is not operating. It is the sub fan in front of your radiator

 

[landtank]

The engine is probably over heating slightly tripping the coolant sensor to turn off the AC. Have you changed out the fan coupler?

 

[cruiserdan]

The engine cooant temp is reaching 226 F and is cutting out the compressor. You still have an over-heating issue or a bad coolant temp switch. I have not seen the latter.

 

[slick621]

Try checking out the fan clutch, i had a similar thing happen to my truck, same symptoms, the fan wasnt turning correctly and turned out that the fan clutch was all messed up

 

[robbie]

Do you ever do a head gasket or check for compression leaks in the coolant? You may of comensated for the head gasket squeeks by the better radiator and did not cure the real problem. later robbie

 

[sjpitts]

The engine cooant temp is reaching 226 F and is cutting out the compressor. You still have an over-heating issue or a bad coolant temp switch. I have not seen the latter.

I have. And CDAN sold me the replacement switch.

Although to be completely honest, that new switch is still in the box. The problem with the old switch went away when I deep fried the old switch. There is a couple of long IH8MUD threads on started by me on the subject.

Now that I have been reminded, I am going to replace that switch tomorrow.

Jared

 

[Taz]

What was wrong with the fan clutch? I can understand the fan helping at idle, but does it help at 60 mph plus?

 

[LandCruiserPhil]

Mark, Are you using the factory shroud with your radiator? I found it necessary to modify the factory fan shroud to get maximum performance with a Ron Davis radiator.

I've said before...the factory water temp gauge is a POS. You could be at 226 degrees and your gauge is a tick above 9 o'clock

 

[tiorio]

Hmm, I discovered I have the same problem but aside from an Optima, my engine compartment is stock. Happened in Palm Springs two weekends ago. Wife was none to happy in the 110 degree heat!

So the consensus is the truck is overheating even though the temp needle is at 9 o'clock, eh? So I have to run a new gauge so see if I am indeed overheating? Urgh. Any other bright ideas to see how hot the truck is?

 

[semlin]

summertime ... and the 80s are overheating

everybody sing...

I have watched this musical two summers in a row on this board. wait til folks start towing.

todd and mark since you have 97s you could try hooking up an obd 2 reader. I believe it will give you an actual temp reading. Optionally you can tap in a mechanical gauge somewhere. there are threads on how and where if you do a search.

otherwise, I would recommend thorough coolant flush (including block drain and heater core), new t-stat, and checking your fan clutch.

 

[Riley]

So how bad is the temp gauge in the 80?

Can you notice overheating at all using the gauge?

My AC has been cutting out too and I have a new AC temp sensor from Dan but I'm not sure I will have time to replace it before heading out for a couple of days. I would like to use my AC and just watch the temp gauge and manually kill the AC if I see it getting hot.

Can I tell if it's getting hotter than normal or is that gauge just crap?

Perhaps I should bite the bullet and replace the temp sensor.

edit - I guess it's pretty quick job to replace the sensor. I'm wondering if I can do it without draining any coolant. Anybody ever replace a temp sensor by just pulling the old one and slapping the new one while the coolant is dumping out the opening? If I work quick I wouldn't lose much and would clean up the mess afterwards.

To do the job correctly, draining a bunch of coolant will take awhile (much longer than replacing just the sensor).

 

[Rich]

Riley,

The factory gauge is bogus. I don't know how hot it has to get before it moves out of the middle. What kind of outside temp and driving condition when your ac cut out?

I have pulled the factory sensor for the gauge without first draining coolant. I did this when I tested the temp response of the sensor. I just pulled the sensor and then plugged the hole with ??? don't remember, something handy. Anyway, the ac cut off coolant temp sensor is mounted at the same height as the gauge sensor, so I would expect similiar results. I don't remember how much coolant leaked out. Some must of, but it wasn't any kind of gusher. Just be forwarned that I don't recall being able to see the sensor while removing or installing it. To the best of my recollection I had to do all the work by feel. So I guess you should be prepared for a little mess, but not a big mess. Maybe do the switch in your neighbor's driveway.

 

[Riley]

Thanks Rich. My AC works in the morning for anywhere from 5 to 15 minutes. Last time I ran it, I was in city driving in the morning and after 8 minutes it shut off. It sure didn't seem to be overheating. That's why I thought I'd gamble and bet on the temp sensor. In most cases it takes hours of sitting until it will work again. Sometimes the next day.

The dashboard temp sensor is reading just below 1/2 half way.

Given there is no path for air to enter the coolant system, the coolant should flow pretty slow I would think. I give it a try tomorrow evening before I head out fishing. Hopefully it will work out ok. It seems pretty easy to get at.

 

[Rich]

Riley, morning time when the coolant is still cold would be best. Otherwise, remove the radiator cap to depressurize the sytem, but be sure to put the cap back on before pulling the sensor.

The only time my ac cut out, it was damn hot out, like 115 - 120 degrees, full load, from back of front seats to liftgate to ceiling packed with gear, climbing extremely steep grades. In those conditions, the engine compartment was so hot that a body could not keep one's hand on anything under the hood, battery, air cleaner, etc, without burning. If your engine isn't hot like that, then I concur with your assumption that either the sensor is faulty or you have some other issue with the AC.

 

[Riley]

Good point about the issue of working on it with warm coolant. I hadn't thought of that. Problem is that I need to work in the morning then pack and drive in the late afternoon & evening. Hopefully my wife won't need to drive in the afternoon and I'll get her to open the bonnet to cool it off until I get home. It will probably be still to hot as that engine really stays warm.

 

[Riley]

Just a little update....

I changed my AC temp sensor before heading off my fishing trip last night. It took all of 15 minutes and I didn't bother to drain any coolant. Just pulled the old sensor and popped the new one in. I only lost about a cup of coolant on the driveway. I washed it up quickly to prevent any sick animals.

It's like a 1/4 banana job. Super easy to get at all things considered.

So far so good as my AC seems to be working well but it hasn't been that warm out so it will take a few weeks to see if it's really fixed.

 

[IdahoDoug]

Let us know.

DougM

 

[Rich]

Catch any?