Of course you can put it in upside down.

The coil goes toward the engine...

 

A.W.T.

Notice the "?" mark on my upside down comment, didn't want to insult anyone.

Best to you

 

I used to have the same problem with my '58 F100, the 223 never got hot enough in cold weather. I used to keep a piece of 1/4" plywood blocking 3/4 of the radiator in cold weather.

 

IIRC the heater hoses bypass the t-stat on the 351's too. Gotta go look under the hood tomorrow. Some carefully placed cardboard (with an opening to allow some airflow) may help out.

 

This is TRUE. I had the same issue, truck never got off of C. Replasec thermostat, flushed heater core with rust remover (you wouldnt believe the CRAP that came out of it). No luck. Finally checked the new t-stat and what do ya know, stuck open. The pin was pushed right out of the housing wedging itself holding it open. Needless to say when you buy a Tstat at the auto parts store get the more expensive heavy duty one.

No problem since, heater willmake you sweat in 30 deg weather.

 

The photo of water temp gauage, mine does not make it to the first line near the "C". I will try changing out the thermostat again but I will test the next one!
Charlie

 

the photo of the temp guage is exactly where mine sets. and after a cold start 15 min later im turning the heater down because its so hot in the truck. and i dont use cardboard in front of my radiator.

 

^^^ same here! Except, takes abit longer than 15min, but once warmed up, it blows hot! Ford heaters are the best

 

AMEN!!! they are the best

 

Charlie57,

Let us know how you make out with the T-stat change. I would get the more expensive heavy duty, 195 degree stat as Mdula advised.

Best to you

 

My 7.5L barely creeps up over the line into normal, never makes it to "N" even towing. I think a thermostat change may be in the cards for me as well because the heat is not hot.

 

...and it doesn't. No "recirc" setting on my F250 climate control...oh well, guess I'll live with cold interior during times of winter.

 

My '89 7.5 Heats up fast as well. Drove it today after sitting for over 24 hours in 19-20* weather and after about 15 mins or so the heater was blowing warm air, another few minutes and I had to turn it down a bit, i was sweatin and the wife was complaining...LOL I;d say a thermostat as well, even if the heater core bypasses it, (I don't know much about the 7.5L admittedly, I've only owned one for a few days...LOL), the motor would still need to get warm to heat up the coolant that goes through the heater core. I wonder if air in the system would cause something similar....

 

I'm sure there is some way to shut off the outside air in your truck.
the labels on the heater controls may have changed but it's not likely the functions did.
Perhaps you have a broken vacuum line to the blend door motor near the passenger side hood hinge?
The default is open, and then the heater core only gets one pass to warm the outside temperature.

I just noticed that my truck was not warm enough for my old bones. I then replaced the temp sender and thermostat.
Turned out that plastic vacuum line had broken again! (farther up than where I had repaired it a few years back.)

 

My 2008 F250 blows cold air during the winter. Yet, when it gets above 40 degrees outside, it kicks on. Mine is a 6.4L Turbo diesel. I thought about putting cardboard in the front of the engine. Wouldn't that cause the engine to overheat?