I have a Ford F- pickup with two-wheel drive a...

Dear Car Talk

Dear Car Talk | Dec 01, 1999

Dear Tom and Ray:

I have a 1979 Ford F-100 pickup with two-wheel drive, a 302 engine and only
60,000 miles. My problem is heat. In the winter, there's enough to defrost ice
off the windshield, but not enough to warm the cab. I've flushed and back-flushed
the radiator and the heater core. It appears there are no clogs. The temperature
gauge rides right in the middle of the "normal" section. But I'm cold! What's my
next step? -- Jeff

RAY: Heated socks, Jeff. With a cigarette-lighter adapter.

TOM: Actually, the first thing you should do is check to make sure the engine is
heating up properly. You do that by sticking a thermometer in the radiator as the
truck is warming up. The dashboard gauge probably is correct, but it's worth
checking before you go any further.

RAY: Assuming that your coolant is actually getting hot enough, then I'd throw in
another heater core. Even if the flow through your current core appears to be OK,
it could be so encrusted that the corrosion is acting as an insulator and
preventing heat transfer into the cab. And in this truck, the heater core is easy
to replace.

TOM: If that doesn't do it, then the problem might be in the vents. If it seems
worse when the truck is moving, your vents may be letting in too much cold,
outside air.

RAY: And if all else fails, since your car is of legal age (over 18), you have
our permission to put a piece of cardboard in front of the radiator and forget
about it. Good luck, Jeff.

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