Vent System & Overheating - 1979 450 SLC
 

I have a 1979 450 SLC that I just purchased. I do not have complete maintenance records. Air only moves through the far left and far right vents and the defrost vents. No air comes throught the center 3 vents. Air only moves through the operating vents when the a/c is on. Are there electronically controlled baffles that redirect the airflow? Maybe a vent connection was accidentally disconnected? There is also a problem with the car running hot. I know that work was performed on the cooling system prior to my purchase without success. I have to assume that the mechanic checked the obvious (i.e., thermostat, blockage, etc.). I tested the antifreeze and it is up to par. It was mentioned to me that this could be related to the timing chain???? Do you think there is a relationship in someway between the two problems.

THanks.

Running hot, bad emissions...

I'd check to see if the ignition timing is correct (sufficiently advanced).

The AC problem is probably vacuum related, the flaps are moved by vac.

Start checking vacuum lines in the engine compartment -- the green plastic lines are for the climate control. You will find that the rubber hose parts that connect the plastic lines are all shot unless replaced recently.

Have a care with the plastic tubes, they will be brittle by now.

Try applying a vacuum to the green line and see if the climate control then works properly -- the fan is switched off if there is no vac in the system.

A large vac leak can make the engine run lean, causing overheating, but I'd bet on a clogged radiator myself, given the age.

Peter

I appreciate the input. I obviously have some work to do - - when I can find the time. Lucky that this is not my primary transport.