How does one determine the exact build date for my 2002 Ranger, 2.3 engine? I'm trying to determine if the coolant should be green (built before 7/15/2002) or gold, built after 7/15/2002. I can't seem to keep it from over heating. I've replace the thermostat, water pump, reservoir and cap, hoses, everything!
Jack in Albuquerque

 

Gold/yellow is HOAT based coolant so can be used in any year vehicle, from 1901 thru 2023, it also can be used for 5+ years without changing it

And using green(2 year, silicate based) or gold, or just water, wouldn't be the cause of over heating
Coolant is used for anti-corrosion of metal parts in the engine's cooling system, and for anti-freeze in colder climates, not because it cools better than water

The 2001 and up 2.3l Duratec engine uses a CHT(cylinder head temp) sensor for computer and a Coolant Temp Sender for the dash board temp gauge
Is your overheating an actual boil over or just the dash gauge or computer code?
i.e. is the engine actually overheating?

CHT sensor will show 250-260degF as normal operating temp
Dash Temp gauge should be just below 1/2 when engine is warmed up

Cold engine
Coolant level at correct COLD level
Degas bottle cap off(reservoir cap)
Start engine
Watch the Degas bottle for bubbles, might be a few but NOT a steady stream
Steady stream means blown head gasket or cracked head, which causes overheating because it displaces coolant in the head, pumps air into cooling system
Or if Degas bottle overflows within a minute or two, same conclusion

 

Thanks RonD - the steady stream retuning to the reservoir is exactly what is happening. Probably the head gasket or (gulp) the head is warped. It has been running hot for some time. Are replacement heads readily available for this engine OR can the head be machined flat if it is warped? I doubt it can be repaired easily if it is cracked , right? I appreciate the help. Jack in Albuquerque

 

There is a chemical test you can do called a Block Test
It tests the coolant for Exhaust gas residue, this would confirm a cylinder leak to cooling system, but from "steady stream into reservoir" thats what it reads like

Blown head gasket is the more common reason, 2.3l Duratec was not known for cracked heads like say a 4.0l OHV engine, it can happen just not as likely
You first need to remove the head
Then take it to a machine shop where they pressure test it, that's the only way to see if head is cracked, unless you can visually SEE a crack, lol
If no cracks then machine shop can clean and surface the head(make it flat)
Maybe do a valve job if you want

Remanufactured 2.3l Duratec heads run $500 - $650 exchange
Machine shops can take a few weeks to do a head, so many just get the rebuilt head so they can remove and replace, so vehicle is up and running in a few days

The timing chain can be hard to setup on these so read up on that as much as possible