2002 2.3L overheating

[DieselDude]

So I have a 2.3L, trying to figure out why she's overheating... I've read exactly what I'm posting now just can't remember where anymore. The upper radiator hose is burning hot, lower hose is cold. When I turn on the heat, temps drop to below normal operating temps. Code reader w/ live data was reading around 230. I'm really hoping I'm just looking at a clogged radiator and not a bad thermostat. Anybody have any ideas?

 

[RonD]

Welcome to TRS

Unfortunately it reads like thermostat would be likely cause.

You have the 2.3l Duratec DOHC engine in an '02 Ranger
Thermostat and housing are one piece and located on the LOWER radiator hose.

Most engines have thermostat on Upper hose, so hot upper rad hose and cold lower hose would suggest clogged rad.
When thermostat is on lower hose then thermostat would be more likely than clogged rad.
And with this engine the thermostat is not an uncommon failure.

I would certainly run water thru rad once system is drained, just to be sure it isn't clogged, but I think it will be clear and thermostat will need to be changed.

 

[pjtoledo]

the radiator is easy to test.
remove both hoses, put garden hose in top, see how much comes out the bottom.
since the heater reduces the temp, the water pump is probably ok.

FYI, the 2.3 being an over head cam, does not like severe overheating.
if the head warps both the head surface AND the cam saddles are out of alignment.

 

[pjtoledo]

user Soledad has some posts about overheat issues on the Duratec 2.3

 

[DieselDude]

Just ran the engine to above normal and that radiator is still cool to the touch... I suppose first I'll dump out the coolant and like you said just try with a garden hose. So does anybody know if there's a way to test the stat outside of the vehicle with this stupid electronic stat?

 

[RonD]

The electric thermostats heat up electrically so wires connected to them are not for a sensor.
If possible check the 2 wires for voltage when key is on and look at the connector inside thermostat housing they can get fried, pictures here: https://www.2carpros.com/questions/ford-ranger-2002-ford-ranger-23l-4cy

This is a heating element so will draw some AMPs, I don't know where the fuse for it would be, should be in the manual.
But I would expect the computer to monitor this voltage and would turn on the CEL(check engine light) if there was no voltage.

Trouble with pulling this unit out for testing is that it requires alot of disassembly to get too, so almost better to just bite the bullet and get a new one since they are known to fail.

Yes it does need to be the electric one.

 

[Soledad]

I've got a few posts on this board and some other Ranger/Ford Truck boards regarding my overheating quest on my 2003 2.3L. Search for my username on them like pjtoledo noted above. These cooling systems are a bit more entailed than the older 2.3 Lima engines.

Oh and it is normal on these 2.3 Duratecs to have a hot upper hose and a cool to slightly warm bottom hose. It's the nature of the beast on these.

 

[DieselDude]

Unfortunately when I left school this spring I left my toolbox since I had no way of bringing it home and among the tools I left was my multimeter. BTW I took off the upper radiator hose and it just ripped so probably time for a replacement on that...

 

[Soledad]

Oh hey, check that long steel tube that the upper radiator hose connects to while you have the hose off. Mine was completely rusted out on the inside from the orginal owners cooling system neglect. If it is rusty on the inside it should absolutely be replaced.

 

[DieselDude]

Yeah she looked a bit rusty on the inside. By the way, what kinda coolant should I be running in this? Guy at O'Reilly said the green stuff but I've heard otherwise on various sites.

 

[Soledad]

Ok yeah then I would definitley replace it if it's rusty. I believe the Motorcraft Part Number is RH91 and it's about $45. It's pretty easy to replace. Just use a ratchet strap to pull it off if it's really stuck in place.

As for the coolant, check this out:

https://www.fcsdchemicalsandlubricants.com/main/quickref/coolantsEN.pdf

Model Year 2002 was a split year for coolant. If the truck had a build date before 7/15/2002 it uses green coolant. If the build date is after 7/15/2002 it uses gold coolant.

Also, in one of my older forum posts RonD (I believe it was RonD) had an excellent post on the differences between green, cold, universal and etc coolants. Definitely worth a read.

 

[DieselDude]

Oh yeah I've read through your posts a few times and I believe I read about the differences as well. Truck says build 8/01 so must be green.

 

[DieselDude]

So I've figured out that it is indeed the thermostat. If I fan figure out how to add images I will do so.

 

[DieselDude]

 

[DieselDude]

[/URL][/IMG]