1984 Ranger 4x4 2.8 overheating

[1984rangerdanger]

I recently bought an 84 Ranger for cheap. 140k miles, body is perfect but engine overheats (on a 100° day it will drive for about 20 minutes on level ground before approaching the top end of the normal range on the temp gauge) and runs a little rough.

I plan on doing the duraspark conversion, but the overheating bit has me thinking I need to tackle bigger issues first.

The radiator feels hot as well as the upper coolant hose. I put in a new fan clutch… but the fan clutch doesn’t seem to be engaging when it gets hot which leads me to believe the hot water is not circulating through the radiator.

Should I be preparing for a head gasket replacement? There is no coolant in the oil, but there was a little bit of oil residue under the radiator cap.

 

[RustyShackleford94]

Have you tried replacing your thermostat and flushing the cooling system? The fan clutch not engaging is a problem also.

 

[Blmpkn]

Have you done the glove test to see if the HG is gone?

 

[1984rangerdanger]

Have you done the glove test to see if the HG is gone?

No I haven’t! Just googled that and I’m going to do that when I get home from work.

 

[1984rangerdanger]

Have you tried replacing your thermostat and flushing the cooling system? The fan clutch not engaging is a problem also.

No I haven’t. Going to do the glove test for bad head gaskets, if they’re good I just bought a new water pump and thermostat to install tonight.

 

[Blmpkn]

Does the fan clutch "hold" and spin the fan when the truck just starts? They're supposed to grab when cold, then freewheel for a bit, then grab again once it heats up enough. Perhaps the replacement is bad right out of the box?

It should go without saying.. but change the thermostat and then check your temps before diving into changing the pump.

 

[dvdswan]

Welcome to the site.

 

[1984rangerdanger]

Just did the glove HG test, no movement at all so that’s a relief! Now on to test the new fan clutch and replace the thermostat.

I’ve read a couple different opinions, but the thermostat is supposed to go on the water pump itself, not under the housing on top, correct?

 

[1984rangerdanger]

Welcome to the site.

Thank you!

 

[ThatOneGuy]

Just did the glove HG test, no movement at all so that’s a relief! Now on to test the new fan clutch and replace the thermostat.

I’ve read a couple different opinions, but the thermostat is supposed to go on the water pump itself, not under the housing on top, correct?

On both the 2.8s I've owned, ive always ran the thermostats on top for a couple reasons, one is ease of maintenance, the true thermostat housing, is a bit of a p.i.t.a, prone to striped threads, and troublesome to seal with that 2 peice design, another is I liked the idea of it responding to top of engine temp, as an assist to prevent to much heat on the heads, does this really do much?, idk but that's how I felt about it.

 

[1984rangerdanger]

I got the new thermostat in, and yeah it’s a pita to seal. Finally had to put a thin layer of form a gasket on both sides. Waiting for it to dry before I pressurize the system. While I was down there I took a look around at the water pump and it looks fairly new. As is the radiator. Looks like the previous owner has already been trying to figure this out…

I noticed there is only the top part of a fan shroud on this truck. Is that normal? Seems like there should be a shroud around the whole fan... I’m thinking if this doesn’t work I may get an electrical fan to put in front of the radiator along with a thermostat switch.

 

[1984rangerdanger]

OK, haven’t had a chance to work on the truck until today. New thermostat installed, refilled coolant from the top hose to eliminate any bubbles. Started it up and let it run for about 10 minutes, at which point it started to overheat again just idling.

The radiator is warm, but not so hot that I can’t touch it. both hoses are warm, but again not too hot to touch. Assuming this means a bad water pump? I left the radiator cap off while it warmed up and couldn’t really see any visible water movement.

 

[Angie]

Let me tell a story. I was able to buy a 92 ranger from a young guy for 400 dollars. he sold it cheap as he said it over heats.. i was intrigued. first thing i did was took out the sending unit for the dummy temp gauge and replaced it with a manual temp gauge and guess what... the temp never went over 200 F... so i got a great truck for next to nothing and didn't over heat. just had a screwed sending unit....

Maybe you should try the heat on the sending unit with a IR thermometer and see if the sending unit is past its expiry date.

cheers, you never know, maybe nothing wrong with the unit.

 

[Rowdy Fitzgerald]

I second checking it with a IR gauge. Then replacing the temp sensor.

 

[1984rangerdanger]

Holy crap y’all, that was it! The dash temp gauge pegged all the way to the top and the hottest my IR gauge read was 183°. Looks like the previous owner put a new water pump and radiator in, while I put on a new fan clutch, all because a faulty gauge. Can’t believe I missed that. The temp sending unit looks brand new, but I’m going to replace it anyway to see if I can get an accurate reading. If not I guess I’ll just install an aftermarket one. Thank you to all who responded!