The Stovebolt Site Forums The Parking Lot '60-'66 Trucks 63 heater question /thermostat/ running cool

Ok, working on the 63 somemore. Have new heater core, and heater control valve working fine. 230 L6 engine, 4core radiator, 180thermostat. Engine warms up and then stays cool. The problem is the defrost runs cool also because of it. Its in the 30's here in the mornings and I would like the heater to be a little hotter. Can I go to a 195 thermostat and keep the engine a little warmer? What about putting something in front of half the radiator to shunt some of the cool air entering the engine bay?

if the thermostat is working properly, the coolant temp shouldn't be less than 180 once 'warmed up', which should be OK for defrost and heater, but don't expect to stay toasty in an old truck ... in freezing weather I cover the rad core with a potato sack to slow cooling

Bill

Ive got the factory guages in the truck, and in summer months the guage will read just a little to the right of center or 90 degrees, in the winter it stays a little to left. After it warms up and the thermostat opens, my heater runs cool air. Runs good and hot prior to thermostat opening. Blower motor, heater resistor, and fan/heater switch work fine. So I guess that I should try and shunt the air flow into the radiator then? I will also check the antifreeze/water mix. If not enough water in the system that would cause it to run cool also...right?

I assume you mean your gauge at right of center reads 190, but the only way to tell the actual temp is use a thermometer on it and compare to the gauge .... amount of water shouldn't have any effect, the rad might be low but the block will be full .... try reversing your heater hoses, you may be getting water to the heater from the output of the rad, when it's coolest, rather than from the engine when it's hottest

Bill

The heater hoses on my truck are as follows: 5/8" heater to engine, and 3/4" heater to water pump.

Another thing to check is the heating element in the back of the underdash heater plenum. The element will glow, red-hot, when the heater is on high. The warm air from the underhood box, blown through the warm heater core, is supplemented by the radiant heat from this element.

Thanks Tony. Im guessing your refering to the heater resistor?
I think they are like $10 new, so it wont hurt to get a new one.

on my 60 to get the heater to work like it is supposed to I had to machine a restrictor to slow the water down goin thru the heater core. I only drive my truck when it is real nice with no chance of snow in the winter months and not much at all in the summer but the few times i did when the weather was cold it was torture before I fixed the thing. Do you by chance have the deluxe heater? When I first put mine together I had a problem with the blend door sticking open also letting air from outside blowing by amplifying the cold air coming in.

Yes, I have the deluxe heater and the heater core with the Ranco heater valve that bolts directly to the core.

Ok, got the core back and everything reinstalled. Getting plenty of heat/defrost now. Is it possible the other core was clogged limiting the amount of hot water flowing through it?

It absolutely is possible that was the issue. Junk does build up in there over the years.