1976 c10 A/C question.....

[truxson]

Hi Folks:
It's been awhile since I posted...but I need some more help with my 76 Chevy truck A/C. 

If the selector is set to 'Max', you get the high speed fan.  Mine will run for a little while (5-7 minutes) and then the fan goes off.   Sometimes you can get it back on by setting the selector to 'normal' A/C and setting the fan at something less than 'high'.  Or....you can wait.  Eventually setting the A/C unit back to max and the unit will come back on for awhile. 

I'm guessing I'm not the first person to have this problem.  Does anyone have any advice as to where to look for this problem?

Regards, david.

[bd]

Check all of the blower circuit electrical connections.  Verify that the ground wire to the blower motor housing is tight and the blower motor is properly grounded.  Inspect the blower and mode switches on the backside of the A/C control panel for signs of melting.  Will the blower motor continue to run if you jump it directly to B+?

[truxson]

Thanks for the suggestion.  I haven't really done a lot of trouble shooting as this just came up when I started getting the truck ready to go to Hershey next week.  Yes....I drive it a lot.  530,000 miles and counting!

I know the fan blower switch isn't exactly the right one.  Probably the 77-82 switch as Chevrolet sold it to me years ago as one that 'replaces number' so and so.  I made a change to the switch to make it work, but it's also suspect. 

Do you happen to have a part number on the item you mentioned on the back of the control unit?  It's been many years since I took this apart for any reason and I don't recall the part you're mentioning.

I appreciate any help I can get...I'd like to find a 'simple' fix before Hershey, but if not, I'll get on it when I get back.  We've had a flea market space there for 30 years or more.....

Regards, david.

[bd]

I drive it a lot.  530,000 miles and counting!

Original motor?   

Better thought:  check the inline fuse holder located in the 12-gauge orange wire where it attaches to the firewall junction block above the back of the engine.  I'll bet it's melted.  Replace it with a 12-gauge blade style fuse holder with a weatherproof cover and install a 25-amp ATO/ATC fuse.

[truxson]

I'll check that tomorrow after work.  Thanks!!