Yet Another No Heat Problem

[steve lyle]

'95 Ranger
2.3L 4 cyl engine
5 speed
105k miles

This is a seldom used vehicle at this point. Drove it about a week ago in 20 degree weather. No heat anywhere - defroster, floor, nowhere.

Eng temp gauge doesn't get to mid-point, gets about half-way there.

Thought it might be the blend door. Blend door is fine.

Thought it might be the actuator for the blend door - cut a hole at the bottom of the plenum and manually moved the door, no change.

Figured the low temp level might be contributing (but prob not, it's been that way forever, and the heat used to work). Bought a thermostat, read up in my Chilton and Hanes manuals on doing the replacement, then popped the hood. How do you change a thermostat on a 4-cyl? It looks like the thermostat housing is buried deep under multiple components at the top of the engine. What a mess.

Even the directions to drain the radiator didn't seem to work - I removed the plug at the lower left of the radiator, and just got a trickle of fluid out. Odd.

Both heater hoses were/are warm - not hot.

There looks to be some sort of vacuum actuated valve on the heater hoses - could that be bad?

Or do I just need to back-flush the heater core?

I did lots of searches of the forums, couldn't find anything on the 4-cyl thermostat.

Any help/advice would be appreciated.

Thanks,
Steve

 

[my98nnj]

The actuator on the heater hose can be stuck in the closed position. Manually move it or simply take it out and put a by pass hose in it's place. Make sure the heater core isn't clogged up. You can flush it with a garden hose by disconnecting the hoses.
Truck isn't overheating, temp gauge seems to indicate a normal engine temp. Mine sits just under 1/2 as well during the winter but I get nice hot heat.