It's been colder but my engine in my 89 V8 never gets to "C". While it sounds like the thermostat, I replaced it about two months ago, because of the same problem.
Any Suggestions?
Charlie

 

Do you get hot air out of the heater? could it just be your gauge?

 

It's cold air. Even if it was the thermostat would it not warm up after 20 miles?

 

No, if the thermostat is stuck open, it won't warm up.
It might if you put it under a big load, but not with normal driving...

 

Try covering the front with a cardboard or something.

 

Try swapping the hoses on the heater core. I reversed them on My Centurion one time and had no heat.

 

Shouldn't matter which way the heater hoses are hooked up.
I sliced a heater core in half and posted the pic's to prove it a while back.
Where are you Charlie? Just HOW cold is it there?
Which V8???
If you replaced the thermostat recently did you use the proper 195* one?
If the ECM sensor (not the dash gauge sender) does not think the engine is warm it will always cause the the engine to run rich and it will be difficult to truly warm up.

 

what engine and does it always stay cold or does it eventually warm up

 

Not trying to hijack the thread, but my 92 F250 5.8L engine never seems to warm up either. Today I drove on the highway for 20 minutes in 25F weather, and my gauge stayed to the low side of "Normal" - but mostly, my heater doesn't put out very hot air...

 

That's pretty normal for these trucks.


My '89 runs a normal temp, and the gauge never even passes the N of NORMAL. Same with my 7.3 diesel.



These gauges are borderline useless...............

 

That's about where my '87 7.5 will get...

If the heat is not enough check that the climate control is on recirculate and you might try setting to a lower fan speed.
FWIW,
My blower works so well that it is MUCH hotter if it is not blowing so fast through the heater core.

 

I never consider the heat "hot" or "hotter" in my truck... ;-) I always use the lowest setting on the blower, and it helps the air be warmer. I will look for a recirc...didn't think of that! (didn't think it had one). thanks!

 

I have the same problem and its very annoying. When it is in the -30s and -40s here, the heat barely works! my 2004 Ford Explorer blows hot air, but my 1993 Ford F150 is still blowing cold anytime its below 0, especially if it is in th e-30s to -40s... It makes it annoying to drive.

 

Have you ever bought a part at the parts store and it didn't work..?

Sometimes parts fail right out of the box.

don't know how big of a deal the job is,? right on top right.? Sounds if it is stuck open.

Take stat out, rinse it off, stick it into a pot of water on stove and boil the water to see if it works. I don't think you can put it in upside down.?

Just my 2 cents.

 

I don't know about other engines but the 7.5 heater bypasses the thermostat.
In extremely cold weather the heater core itself is enough to keep the thermostat from ever opening.

-30 >>> -40 could easily be too much and I would suggest a flow restrictor in the line.