4bt cooling problem, input needed.

[LAlessi]

95 degree weather my 4bt runs 195-200 and no cooling fan in stop and go traffic. it stays around 190-195 at highway speeds. turn the a/c on (it turns on the electric fan) the temperature drops to 185-190



40-50 degree weather the truck runs against the thermostat or 175-180. the defroster (wired to fan too) keeps the thing at 175 and thats not very warm air.



winter is coming again. . soooooooo, i never ran it in 20-30 degree weather, and im concerned



1) put a higher thermostat? (factory starts to open at 175, fully open 200)

2) put a radiator cover, canvas or cardboard when its cold



my thoughts against a 195 thermostat is going to keep the temperature at 195, even when the motor is running efficently. i mean isnt it bad to keep riding against the thermostat???

 

[Philip]

At the temps your running at 175 to 190 that is more than enough heat. I have driven some 715's before and the heaters were not that good when they were almost new.



Have you had the heater core cleaned out at a raditor shop. With its age it is probably stoped up.



I would suggest opening the heater box and seeing if you can put a bigger heater core into it.

 

[LAlessi]

oops. its a vintage air, heat/cool/defrost unit. the unit is actually built for a large sedan, so the thing should be more than adequate heat and cooling (cooling is)

 

[Philip]

Vintage air puts out some good products.



Have you checked to make sure the blend doors are working properly? The temps you are showing with a larger heater assy should run you out of the cab.



Are you running the canvas top model of 715 or a hard top?

 

[LAlessi]

#ad




canvas. so 170 degrees should still be hot enough??? i didnt have it running long enough last cold spell to tell... ...

 

[Philip]

You have the canvas top model I see. Those are hard to heat. That canvas is like a cold sponge. It stops no cold at all.



The blend doors are about my only suggestion. Make sure it is set for reheat of the cab and not pulling outside air. With the heat loose you have pulling any outside air will kill the effenicy.