Heater doesn't work so good - 74 Duster

Loggato said

I have 2 problems with mine.

1. hardly any air flow (fan on high)

Click to expand...

That sounds like a clogged heater core or leaves or other debris blocking it. If it’s clogged up, a reverse flush should help; otherwise open the case up and clean it out.

“Loggato said

.
2. Doesn't get very hot

I think the second can be solved with cardboard in front of the radiator (engine temp does not get very high)(yes, new thermostat), but before I start to diagnose the first, I'm wondering if anyone else has the same opinion.

Thanks

Click to expand...

I’ve never had heating issues with any 60’s/70’s Mopar I’ve owned both brand new and well used. I would find out what the problem is with the engine temp- which affects the temperature of the heater core! “Engine temperature does not get very high” - incorrect thermostat, collapsed upper or lower hose, clogged radiator, does the motor need a thorough flushing to get all the built up crap out of it? Got a thermal gun to check radiator and engine temps. At a minimum check the temp of the coolant with a decent thermometer. A piece of cardboard in front of the radiator is just a bandaids fix.