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Tips

Heater not working. I'm very cold.

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100DashSix

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Well, I'm not sure if the heater isn't working. I do know that the fan switch on the dash of my '74 B will produce a worthwile-sounding hum, but I also know that no air comes from the vents. I have the impression that removing the heater to install a new fan motor is extremely annoying, but I don't know where on the internet I got this impression from.

In other news I put a wonderful new head unit in, and I'm very happy about that.
 
Pull the water outlet to heater thingy first (on the side of the block above the distributor). They tend to get clogged and blocked by scale and all other forms of crud. Take that part off, clean it up good. Reinstall and see if your heat works (and make sure it don't leak). Then if still no heat, go ahead and pull the heater.

Oh... Make sure your car has at minimum a thermostat. My car hasn't had one since I bought it. Just found out this year. If it doesn't have one, it'll never get warmed up.
 
Did you check the floor and the defrost vents to make sure that air is blowing there or just the center vents? The center vents wont blow any air at all from the fan.
 
Replacing fan motor doesn't require heater removal...it comes our pretty easy...however, sounds like you may have vent or hose problems - if not heater control valve...got to my website tech tips for how to clean valve....or go to Bob Munchasen's site fr how to modify for better water flow.
 
Dan, Is the temp gauge reading normal? Or is it pegged in the cold position? If it's cold, you need a new thermostat. If it's normal and you have air flowing out of the footwell vents, (which means the fan is working), then you have a flow problem in the heater plumbing. Look for a blockage in the control valve first as it has a much smaller passage way than the rest of the system and a flake of rust from the block can plug it up easily. I would guess it's the control valve. New ones are avalable if yours is bad. My car did the same thing, but my control valve was bad.PJ /ubbthreads/images/graemlins/hammer.gif /ubbthreads/images/graemlins/thumbsup.gif
 
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