1986 Ranger 2.9 Overheating?

[Davoe Schmavo]

Hello All, I have a 86 2.9 XLT Ranger that seems to read that its overheating on the dash. Ive replaced the following: Radiator, thermostat, and water pump. Im about to replace the coolant temp sensor and radiator cap (current one doesnt leak but feels loose).

Fan blows just fine but Im thinking I should replace the fan and clutch too....thoughts?

It blows out hot air in the cab so I think the heater core is fine (also no sweet smells or coolant leaks).

I love this truck and want to get her on the road soon.

 

[Rick W]

Sounds like you’re covering all the bases. Maybe the gage in the dash? Could the water pump be clogged, crudded up?

I have an 87 2.9. When I swapped the radiator I put in the bigger aftermarket aluminum. How did the antifreeze look? Maybe flush it and check it. Maybe add a cleanser to flush it to clan out the system?

My ‘87 Town Car sat for many years before I got it and the antifreeze looked like mud. I’m not recommending it, but I mixed up
a muriatic acid solution and ran it hot for 30-40 minutes. Clean as a whistle now.

A lot of these guys know much better than I do….

 

[Davoe Schmavo]

Ok, so i checked the thermostat again and made sure it good. Is there a certain way it needs to be seated?

Here's a pic of it after taking it down the road. It doesn't go higher than this. I still have to change the sensor. The nut seems to be bigger than a 24in

 

[Rick W]

I thought I posted a follow up, but I don’t see it. Basically what I said was…

That gauge does look high to me. Mine creeps up to about 25% usually, and on a hot summer day if I’m pulling any kind of a load, it might go to about 60%, but I’ve never seen it approach the top of that bracket behind the needle like that.

How does the antifreeze look? Have you tried to back flush it? Literally, force water, throw it in the opposite direction. You might have a piece of crud lodged somewhere, and hopefully that would push it out. Also, do the chemical scrub with the engine hot, that will clean off some crud.

What about the hoses? Any kinks? Are they the original hoses? A couple of times I’ve had old hoses collapse on the inside, kind of delaminating, that wasn’t obvious on the outside, but it restricted the flow. If you don’t have the OEM type formed hoses, you can get one of those spring, looking things and run it down your hose to keep it cylindrical in cross-section.

It’s not that expensive to get an aftermarket temperature gauge, even if you just use it in the short run, to see if you get the same results you’re getting on your dash gauge

Did you test the thermostat on the stove in a sauce pan? You can put the thermostat cold into cold water and then turn on the burner, using a thermometer, and actually watch when and how the thermostat opens up. Long, long time ago, I had a thermostat that would open up at the right temperature, but it would only open up a little bit. That could make it run hotter.

As regards seating the thermostat, I don’t think it matters where it sits 360° on the surface. I don’t know if on these vehicles, you can actually put the thermostat in upside down. The flat part pushed by the spring should be the intake, facing down. The pointy dome should be on the top, the outflow. If it’s not installed correctly, and it allows bypass, I would think that would cause cooler temperatures not hot temperatures.

My two cents, hope it helps

 

[Davoe Schmavo]

Hey, the antifreeze is clear and i changed out the thermostat with another from AutoZone. This time the guage seems to fluctuate and it'll go up and down. So I'm thinking of doing the coolant sensor and the sender sensor. Also noticed i may have a wiring problem. The lights in the gauge will light up and then times they won't. But it's only on the side where the temp, fuel, oil, and battery cluster are.

As far as fans, what kinda fan can i install? I'd rather not go with a electric if possible

 

[Rick W]

I think it’s pretty unlikely that the light circuit would be affecting the gauges. The gauge panel is basically a big printed circuit board. If the lights are going on and off on one side, that’s a bit unusual. It’s usually in the light switch, but everything would go high low on off at the same time.

On the other hand, you may have a poor ground contact from the circuit board to the rest of the truck. On your next trip to the scrapyard, you may want to pull the dash panel on one of the relics, just to look at it and see how it works. If you take a little time, you could actually trace the circuits on the board to the gauges, and back to the wires.

i’m 69 1/2 years old, and been doing this since I was 14, and I still go to the scrapyard every now and then to pull something apart before I pull my own apart. I’m about to do it for one of my Lincoln town cars.

I’m not too much help on the fan. I never had anything but the stock fan on anything I had. Funny thing is, I’m about to pull a belt drive fan and replace it with back to back electrical fans on my 78 Mark V. It gets hot very fast in stop and go traffic in the summer. But that’ll be the first time I actually swap one.

I would suggest starting a new thread on which fan set up is best for blah blah blah. Again, a lot of these guys know this stuff a whole lot better than I do, I’ve got some gray hairs, but it’s not what I do for a living.

 

[Davoe Schmavo]

Thanks Rick. I think i have a ground loose somewhere in the ignition, or radio. Now sometimes when i crank the truck up, the radio and cluster for the oil, temp and ect don't work. But if i cut it off and turn it just right it'll work fine. Also i think the temp cluster might be wonky. I drove it today and the temp went up but also went down to the middle and just kept doing that. Also no coolant leaks or steam coming out.

LKQ from me has a 90 but that's the closest year I've seen. It's gotta 2.9 as well and going to try and get the fan blade out too.

 

[rusty ol ranger]

Id get a infared thermometer and check the temp at both radiator hoses when its reading like that.

Chances are its electrical. But 2.9's dont take to overheating well, as in, they like to crack heads.

That being said, my truck will do something similar at times, if i put the clutch down the fuel gauge, temp, and oil pressure all rise in tandem with each other.

I never fooled with it.

There is a ground strap that runs from the firewall to the back of the driverside head that grounds cab electronics. Id start there.

 

[Rick W]

Hey, and just another soap box statement.

I fool with a lot of old stuff, many cars and trucks, but also in industry/chemical plants and a lot of commercial real estate. When people have a problem, in my opinion, they run too fast to swap out parts, which can be really expensive sometimes.

I take everything apart, many things I don’t need to take apart, because I want to see what was wrong, or I just want to see how it works. There have been a million times when taking something apart, cleaning the contacts, or doing some tiny easy repair has restored the whatever to 100% reliability.

If you don’t have to rely on this truck for transportation, you may want to simply take the dashboard apart, inspect the circuit board (you can see hot spots and or worn spots.) and clean it and touch it up. On the wire terminals, you can use a fine wire brush to clean them up. You can’t do that with the fine stuff or the circuit board, but I have cleaned fine terminals like that simply by using a piece of typing paper and using it like sandpaper

On all the twist in lightbulb holders, I use a pick to just bend the contacts just a hair, and make sure they’re clean. Look at all the push pin connectors, you can usually see if there’s a hotspot by discoloration on the wire, etc., etc. etc.

Then take all the similar concepts to the connections on the sensors on the engine, where wire clusters plug into wire clusters, etc. If you hunt around on eBay, you can find some very fine spiral wire brushes. I get them, I clip the end of the handle off, and I put them in my Dremel Moto tool. Then you can get down inside connectors and clean the surfaces. And again, you can adjust them with a pick. Pick sets at Harbor freight are regularly on sale for a dollar or two dollars.

just cleaning everything with a mild soapy water, and then rinsing it with Clearwater, and letting it dry can solve some problems. On the gauges themselves, a shot of WD-40 on the spring mechanism or whatever mechanism, or three in one oil, can get you another hundred thousand miles.

I’m sure a lot of these other guys will have other do it yourself options you can use instead of just throwing parts at it. And my last thought, is don’t just target today’s problem. If you’ve got an old truck or whatever, take it apart and look at and adjust and lubricate and clean everything. Either that, or get really good at taking your dash in and out. If you’re like me, I’ve got more time than I’ve got money.

Hey, it’s all my two cents. I hope it helps.

 

[Davoe Schmavo]

Id get a infared thermometer and check the temp at both radiator hoses when its reading like that.

Chances are its electrical. But 2.9's dont take to overheating well, as in, they like to crack heads.

That being said, my truck will do something similar at times, if i put the clutch down the fuel gauge, temp, and oil pressure all rise in tandem with each other.

I never fooled with it.

There is a ground strap that runs from the firewall to the back of the driverside head that grounds cab electronics. Id start there.

Will do!! What are normal temps for this Ranger? Im about to order one from Amazon now.

 

[rusty ol ranger]

Will do!! What are normal temps for this Ranger? Im about to order one from Amazon now.

Should be right around whatever temp your thermostat is. Factory is 190 or 195. I usually run 180's in them.

 

[Davoe Schmavo]

Hey, and just another soap box statement.

I fool with a lot of old stuff, many cars and trucks, but also in industry/chemical plants and a lot of commercial real estate. When people have a problem, in my opinion, they run too fast to swap out parts, which can be really expensive sometimes.

I take everything apart, many things I don’t need to take apart, because I want to see what was wrong, or I just want to see how it works. There have been a million times when taking something apart, cleaning the contacts, or doing some tiny easy repair has restored the whatever to 100% reliability.

If you don’t have to rely on this truck for transportation, you may want to simply take the dashboard apart, inspect the circuit board (you can see hot spots and or worn spots.) and clean it and touch it up. On the wire terminals, you can use a fine wire brush to clean them up. You can’t do that with the fine stuff or the circuit board, but I have cleaned fine terminals like that simply by using a piece of typing paper and using it like sandpaper

On all the twist in lightbulb holders, I use a pick to just bend the contacts just a hair, and make sure they’re clean. Look at all the push pin connectors, you can usually see if there’s a hotspot by discoloration on the wire, etc., etc. etc.

Then take all the similar concepts to the connections on the sensors on the engine, where wire clusters plug into wire clusters, etc. If you hunt around on eBay, you can find some very fine spiral wire brushes. I get them, I clip the end of the handle off, and I put them in my Dremel Moto tool. Then you can get down inside connectors and clean the surfaces. And again, you can adjust them with a pick. Pick sets at Harbor freight are regularly on sale for a dollar or two dollars.

just cleaning everything with a mild soapy water, and then rinsing it with Clearwater, and letting it dry can solve some problems. On the gauges themselves, a shot of WD-40 on the spring mechanism or whatever mechanism, or three in one oil, can get you another hundred thousand miles.

I’m sure a lot of these other guys will have other do it yourself options you can use instead of just throwing parts at it. And my last thought, is don’t just target today’s problem. If you’ve got an old truck or whatever, take it apart and look at and adjust and lubricate and clean everything. Either that, or get really good at taking your dash in and out. If you’re like me, I’ve got more time than I’ve got money.

Hey, it’s all my two cents. I hope it helps.

Yeah before I saw how easy it was to replace alot of parts on this truck I took it to my mechanic to redo the power steering since I paid them and its still leaking.

But once I get it back I plan on taking off the dash to clean and make sure the wiring is all set up correct.

Anyone have any recommendations on running a separate temp gauges or HUD?

 

[RobbieD]

Anyone have any recommendations on running a separate temp gauges or HUD?

A 2.9 does not like to overheat; the heads are prone to crack if it does.

On my '90 B2 I just added an old-school, inexpensive add-on set of coolant temp and oil pressure gauges hung under the dash. It's easy enough to install the add-ons so that the stock gauges also still work, and I like having two sources of (important!) information.

I like having dual temp and oil gauges so much that I'd like to add them to all of my trucks, in an A-pillar mount. Maybe one of these days . . .

 

[Davoe Schmavo]

What aftermarket gauges did you get for your truck

 

[RobbieD]

What aftermarket gauges did you get for your truck

I'm not sure, unless I go look at them. Whatever was the typical back in the day; Autometer maybe?

And I actually "harvested" my set from a junkyard donor. Old, simple stuff works forever.