Dear Scotty,
I love your content and your straightforward approach! I have a 1977 Lincoln Versailles with 71,000 original miles. The car runs like a top and the 351 Windsor idles so smoothly that I have to check my sideview mirrors to make sure I haven't stalled at a red light. Now that winter is upon us in the Keystone State, I feel it's time to take a look a my A/C. Believe it or not, the A/C runs very well. It blows cold air and keeps the cabin cool in the summer (it's not blowing ice cubes, but that's to be expected). However, I noticed that when I run the A/C, it pulls voltage away from the battery. At idle, the alternator delivers 14.5 volts to the battery, but when the A/C is turned on, the battery gets only about 10.2. Obviously, this is not enough to recharge the battery and if I run the A/C too long, the battery dies. The battery is new and is working as expected. I haven't gotten into anything yet, but you always say to start with the simple things first. My initial suspicion is that it is either the alternator, the voltage regulator, or the A/C motor clutch. Any tests you recommend? Should I start with those components or is there something I'm overlooking? Thanks for any advice you have on this "old school" car without codes.
I would start off with checking the alternator. I don't think that your A/C motor clutch is having any issues if you're saying that the AC works fine.
I agree. The alternator could be acting kinda sus. 🙂 Thanks for the advice!
I remember those. They're actually quite nice cars but Ford's biggest mistake was to leave it looking way too much like the Granada it sprang from.
On a car that old everything is suspect. Obviously you'll want to have the alternator tested. If it tests good check battery cables and the ground strap between the engine and the chassis, as well as the battery. (Even though new it could be defective.)
I know what you mean, I always call it my Lincoln Granada. However, the Genius of Lee Iacocca was to use as many parts across as many models as possible, so there's an abundance of parts still around. Thanks for the advice. I too suspect the alternator but will check the ground strap and battery first. Everything else works fine electronically. Power windows, power locks, lights, and even the cigarette lighters. The good thing is I have about 6 months before I really need the A/C again.