Truck is 1994 2.3 L

For years I have had a very cool engine, low cabin heat and with minimal movement on the temperature gage. I read all I could find and changed many items and flushed system. Still not happy.

Today I found this YouTube video and my heating problems are gone. 150+ degrees out of dash vents!
Don’t watch past 6:00. The relevant info for my post is up to that point only.

The fix was bleeding air from system. I squeezed and squeezed the radiator hose getting burps and burps and burps out of radiator and into my funnel (sealed into radiator inlet with a grocery plastic bag). When I got no more air burps I removed the funnel and inserted and closed the radiator cap. I revved engine and temperature gage rose into “normal” and then after a few minutes it fell to cold as the 192 deg tstat opened and then the temperature gage rose back to normal again and HOT air from heater. Yay!

As you can see from my sketch you will have lesser? flow from the large radiator upper hose in a reverse direction and with cold! water due to the thermostat housing smaller tube outlet sucking water from the upper large hose for a while until the thermostat opens and provides the proper flow from engine to small tube and from there to heater core inlet.

Bejingie

 

On any vehicle with heater core hoses located higher up on the firewall you can just remove either one of the hoses at the firewall, then refill the system until coolant is coming out of the unhooked hose and the open heater core port
Put hose back on
All the air is out of the system

Air gets trapped on the engine side of cooling system because the thermostat is closed
Heater hoses are on the engine side of thermostat
Opening up a hose lets the air out so refilling is easy

 

RonD

Thanks

I wonder why I didn’t know that? I am 75 and never bled air from any car coolant system ever in my long list of buggies.

I think there are still many out there with cold Rangers.

 

Any one with a 2.3l Lima for sure
The 1974 thru 2001 2.3l and 2.5l SOHC Lima engines were built like a tank, very heavy engines but lasted forever, very good design
But in colder weather they have a hard time staying at operating temp, 190degF
Too much metal to keep warm in a cold engine bay with cold air coming thru the grill
People often have to put cardboard behind the grill to keep these engines warmed up in winter months

You can even get 200-205deg Thermostats for them

But yes easy to trap air in these, most engines/water pumps will purge the air after partial refill and you start the engine then top it off

 

“””most engines/water pumps will purge the air……””” unquote..

yes, but not Ford Ranger 2.3L….