I bought a 97 Ranger about six months ago, and it's been running great. Just recently its been getting hot, so I naturally tried to use the A/C. Here's what happens when I try to use it.

1.) I turn my Max AC setting with the temp dial all the way on the coolest setting.
2.) Warm air initially comes out, then in a couple minutes nice freezing cold air blasts out.
3.) As cold air comes out, my temp gauge starts to creep up. After only 2.5 total minutes of cold air, the temp. gauge dial points to the highest heat reading.
4.) As the dial reaches "hot" the cold air coming from the vents goes warm and then hot.
5.) As far as I can tell the gauge stays "hot" until I finish driving, and no more cold air will come out until I turn the car off and wait a good while.


At first I thought this might be the classic "blend door" issue, except for the fact that I do get cold air at one point. I have no real knowledge of cars, apart from searching this forum and looking at all the other Ranger AC issues, so any advice would be of great help.

-John-

 

If the engine itself overheats , the AC compressor is supposed to shut down (hence the hot air coming out of the vents).
You need to find out what's causing the engine to over heat.
Start by checking the radiator for debris ,leaves,bugs,dirt,ect.
Is the radiator full and is there enough coolant in the reservoir tank.
With the engine off and cold is there anything floating in the coolant in the radiator ?
When turning the radiator fan by hand does it have a slight resistance or can you spin it easily ? If it spins freely you may have a bad fan clutch.
Have you changed the thermostat ? Change it anyway . Even new ones can be bad out of the box.
With the engine cold and radiator cap removed , start the truck . As it warms to operating temp you should see the coolant start moving in the top.If it gets up to temp and you see no coolant flowing at all , bad water pump.

What engine you got ?

 

Ok, thanks for the advice, here's what I did.

1.) Checked the radiator coolant level and quality: It is full and besides being murky I did not perceive any debris which might cause problems (Checked it when engine was cold, and checked when hot).
2.) Checked oil level (was low, so added a quart).
3.) Checked the radiator fan twice (when engine was hot and cold) and it gave slight resistance both times.
4.) I test drove it again tonight and the cold air on Max AC lasted a lot longer (it was much cooler weather and I drove slower and less distance than when I tested it last). My Temp. Dial steadily rose to the top heat mark, and the air started to run luke warm.
5). When I stopped the car, I opened the hood and checked the top small hose which connects the coolant with the radiator cap part. It did not seem warm, yet the hose/section under the radiator cap was hot.
6). *Edit* I started car with the radiator cap off and watched coolant level. It was a couple inches low at first, but as the car warmed up the level slowly rose to the very top. It didn't appear to be circulating at any great rate.
7.) I have not changed the thermostat, but I plan to. I found one Here but I'm open to suggestions if there is one of better quality/cheaper.

I'll order it ASAP if someone can confirm buying it would be a good next action.

I do not know how to install it, however, and I've tried googling and searching how to install a thermostat on a 97 Ranger with a 2.3L engine.

Does someone know a good tutorial for how to install a thermostat?

Thanks much!

-John-

 

does it overheat without the a/c on?

and from dead cold start it up and drive it.. as it starts to oveheat, meaning past normal operationg temp, shut it off and go out and carfully touch the upper and lower radiator hoses. they should be close to the same teperature. if not you have a coolant flow problem, clogged radiator, stuck thermostsat or bad waterpump.


JOSH

 

Alright, thanks for the advice, I took it for a drive this morning.

1.) Started driving (AC off, engine cool)
2.) After 10 ten minutes ~ of driving temp gauge went over normal operating mark. (Good suggestion Josh, I wouldn't have thought of no AC)
3.) I stopped, opened the hood, then felt both the upper and lower radiator hoses. The upper hose was only slightly warm, while the lower hose was quite hot.

So you say I could have something clogged in there and/or a bad waterpump?

What are my next steps?

(Thanks to OTRtech and Josh so far for advice)

-John-

 

The upper hose should be hotter than the lower.
The next thing to do would be to flush the cooling system.If flushing doesn't cure the problem then it's time for a water pump.
Did you change the thermostat yet? It could be sticking closed not letting the coolant circulate properly.

 

I thought the thermostat fails in the open position?

 

Hmm, I was looking under my car for the coolant drainage plug when I realized I might have made a mistake on identifying the "upper" and "lower" radiator hoses.

Here's a pic of my engine.

Someone please identify the hoses correctly! (pretend #2 is an ex ray)

Also, where is the thermostat located, I seem to find it!

Thanks again

 

2. Lower Radiator hose
3. Upper radiator hose
and if i am not mistaken the thermostat will be at the end of hose #3 where it connects to the engine block....please correct me if i am wrong on anything

 

For the ac, when was the last time you recharged your system?

 

They can fail open , closed , or halfway.

 

# 1 goes to the coolant recovery tank (which should have some antifreeze in it).
On #3 , follow the hose to the left to the elbow . The bottom of the elbow connects to a removeable flanged fitting with 2 bolts.Remove that and you'll find the thermostat.

 

If #2 is the lower radiator hose, and #3 is the upper hose, then they were both hot when the engine overheated. I mistakenly thought #1 was the top radiator hose (this is why I'm asking for advice).

I have not recharged my system (not sure what "recharging" does), and I do not know if the previous owner has done it or not.

Ahh, that's where the fabled thermostat is located, glad to finally get some confirmation.

Alright, I think I'll head over to Kragen Auto Parts to buy a thermostat. Am I correct in thinking I should drain coolant 1st, then open and install the new thermostat 2nd?

\o/ Thanks again guys, and in particular OTRtech for the advice!

-John-

 

Drain out about 1 - 1 1/2 gallons and you'll be good.
Did you check the fins in the radiator to make sure they're clear ?
Too much dirt and crap built up will restrict airflow and cause trouble.

 

Yeah I just checked, and despite some unlucky bugs it appears the vents are about 95% clear.

 

Drain and flush the coolant system. It's ability to transfer heat drops as it ages. I used to plow snow and mid way thru my 2nd winter with a chevy the engine power died with a load of snow in front. Turned out the coolant was old and discolored. Changed it out and things were good.

The A/C is putting a heavier load on the system. Good luck.

my .02

 

Alright, so after finally finding a small enough bucket I managed to drain out all the coolant. Then I tried to take out the thermostat housing, and that's when I hit my main problem; I can't reach the bolts. Even if the hoses and pipes were not in front it would be a difficult place to get to. I managed to use a small mirror which I weaseled down far enough to check and make sure that, yes, there are actual bolts holding it into place, but I'm baffled as to how to reach the 10mm ratchet down there. I tried several attachments and extensions, and eventually I had to give up. Even if I were to get the easiest bolt (top right) off, the other two are even more completely buried.

I tried to remove the top radiator hose so I could see better but it was stuck so firmly on I could not even budge even after removing the metal clamp. I've found the ends of the other hoses in the way and they look like they would take a considerable amount of work to remove, much less replace. Man this has really got me stumped.



-John-