Engine Temp & AC problems
 

So, I'm completely new here. I actually joined because I was hoping I could get help with this problem. In my Ranger - 1996, Extended cab, 4 cylinder engine (can't recall the size at the moment), and manual transmission - I'm having issues with high engine temp. It doesn't OVERheat, but the needle likes to hover around the top of the gauge and it's making me nervous. Also, when this starts to happen, the AC starts to cut out periodically. I had it looked at by a family friend who runs a mechanic shop on the side, but he said he didn't see anything wrong with it. But he also said that he couldn't get the engine to get higher than halfway up the gauge, so I don't know if he got a chance to test it thoroughly since these problems typically happen on the highway after 30-40 minutes of driving. He basically suggested to drop it down from 4th gear when I get into traffic. I took that to mean I run the gears too low - which I have a tenancy to do.

My question is: Should I be terribly worried about it heating up so much (very close to the top bar at times)? Or should I just chalk it up to my poor manual transmission operation and forget that it happens?

I'm not doubting that the guy we had look at it knows his stuff. I'm just worried that he might not have known what to look at because he couldn't make it heat up when he drove it. It may not be the same, but when I'm fixing a computer, it's a lot harder to fix the problem when you can't see it yourself.

Re: Engine Temp & AC problems
 

Sounds to me like your water pump could be rusting out. When is the last time the water pump was replaced? Is your coolant resevior have any brown color or metal flecks in it?

Water pumps rusting through are common on Rangers. I would guess that the fins on the pump have rusted so it is still circulating coolant, but not working effectively the way it should. This would lead to higher engine temperatures but not necessarily over heating. I would not be too worried as long as the temp does not get to high.....but this is definately something you need to keep an eye on. Obviously, if you let the engine overheat, it will quickly seize your entire engine and you will have way bigger issues.

Re: Engine Temp & AC problems
 

I'll check the color of the coolant, but I do remember it looking dirty or slightly brownish last time I checked.

I have only had the vehicle for about a year, so I don't know the last time anything was replaced. I guess then, the water pump would be what pumps the coolant throught the radiator? How difficult would that be to replace myself? (I have very little mechanical experience)

Re: Engine Temp & AC problems
 

Overheating a higher RPM is a sure sign of a failing water pump. The impeller vanes rot out and and can't move a great enough volume of water to keep it cool under that kind of heat load.

As for the AC, I'm not aware of the computer doing that on purpose when the engine temp gets above normal. It is possible and plausible though.

Re: Engine Temp & AC problems
 

Well, the coolant is definitely dirty. It's a murky sort of muddy rust color.

I don't see any flecks of rust, but would it be a good idea to change out the water pump anyway?

Or should I just replace the coolant and wait to see if it gets dirty too quickly?

Re: Engine Temp & AC problems
 

I do not think it is a diffucult task....I'll see if I can track down a do-it-yourself (DIY) post somewhere. I would definately recommend you swap it out yourself, even with little mechanical experience. The part is only like $60 (of the top of my head) and the job is only an hour or two tops. You will definately need to flush out your coolant/radiator system to get all the nasty rusty stuff out.

To do that, you basically fill up the radiator with water, run the vehicle for a minute or two with the vent van on HIGH and the HEAT on as hot as it will go. Turn off the vehicle and drain the fluid from the pet**** at the bottom of the radiator. Repeat until fluid comes out clean. You can also buy a can of radiator flush which works pretty good....it will assist in getting some gunk and stuff out of the lines. I would do the flush BEFORE you swap out the pump.

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YES....I recommend you change your water pump ASAP.

http://www.fordrangerforum.com/how-s...placement.html

http://www.ehow.com/how_5692945_remo...rd-ranger.html

It is not necessary to have the heat on or the fan set for high. As long as the HVAC selector is in a setting other than off or Max AC, the hot water valve is open and water flow is the same. Temperature and fan speed are irrelevant.

[Posted with my Android mobile device using Tapatalk Pro]

Re: Engine Temp & AC problems
 

I thought you put the heat on full blast to expedite the thermostat opening???

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I just realized that the website bleeped "pet.c.o.c.k"......that is the appropriate terminology!

Re: Engine Temp & AC problems
 

Umm, no that would make it take even longer to warm up.

You need only have the HVAC control in a position other than OFF or MAX AC so that the coolant can flush from that part of the system. If you leave it off, it will not flush the heater core or it's two lines.

Re: Engine Temp & AC problems
 

So, I should just swap out the pump? I don't know when the fluid was changed last, so I was planning on draining it, flushing it, and replacing the thermostat since it's all relatively cheap. Then if that doesn't work, I was gonna look into other options like the water pump. But, correct me if I'm wrong, you would recommend swapping out the pump anyway?

If I do need to swap out the pump, I have the "Haynes Repair Manual" for the year & model of my truck. I've looked at it and it give pretty good instructions, so I should be able to do it myself. It's really just a matter of money and convincing my dad it needs to be done (as the vehicle is still technically his and he doesn't like me screwing with his stuff. lol)

Re: Engine Temp & AC problems
 

The water and thermostat condition would not cause that alone. The pump is the most likely cause of your problems.

Re: Engine Temp & AC problems
 

Replace the pump, flush the system......than see what happens. You dont need to replace the thermostat.

Re: Engine Temp & AC problems
 

Alright, thanks! I'll let you know what happens after I get around to replacing it. It'll probably be a few days at least. I'm finishing up work for a few summer classes & an internship.

Re: Engine Temp & AC problems
 

Dont forget to check your radiator also make sure it dosnt have any blockages.

Re: Engine Temp & AC problems
 

i would recommend a good coolant flush to clean out the radiator and block as much as possible then change the thermostat and water pump at the same time. while t-stat is out flush it out good, make sure water flows through your radiator and comes out clean