Posted by Tom Laskowski on November 05, 1998 at 20:33:28:
In Reply to: Heater diagnosis posted by Matt S. on November 05, 1998 at 16:22:19:
: The heater in my 73 Mav. 250 doesn't seem to ever get warm. The fan works fine, it just blows out cold air. I have read some postings here about the "heater core"; does that just need to be replaced? If anyone could give me the skinny on how or what I need to do I would appreciate it, and you will get a "thank you" post (I'm not ungreatful).
:
Steve had a good idea,you can look under the dash at the top of the heater to "see" if the cable is opening the "door",A few other things that are quick and easy to check. Is your cooling system full? (when's the last time you checked?) The 250 will run low on coolant and not overheat, but you will not get flow to the heater,hence little or no heat.Are Your heater hoses hooked up,and do you have a thermostat in the engine,and is it working?
If all the above "check out" then try a reverse flush on the heater core. It will remove the rust,sludge and other matter,("BEWARE") but it may also spring that leak you didn't know you had if this happens "THEN" it's time to replace the heater core. Good luck!