Summer time in Arizona is very hard on batteries. The continuous heat accelerates every bad process that kills batteries. So keeping a bunch of Cougars running that are not driven much when the temperatures are above 100 degrees can be challenging. I try to fire up the cats at least once a week in summer and drive them at least some about every other week. Temperatures inside my insulated barn get to about 115 on the hot days.
Here is what I have learned that might be of some value:
All three of these Cougars were starting and running fine the week before.
Cougar 1: Engine cranks well but won’t fire. Solution, add fuel through vent in front fuel bowl and then a little more down the carb throat. Fires up and runs well. Settles down to idle as the factory choke heats up. Battery on tender from Harbor Freight.
Cougar 2: Engine won’t crank. Solenoid clicks and buzzes. Battery was on a trickle charger from Schneider. Put on regular charger. Still won’t crank. Put battery tester on top of cable clamps. Showing full charge voltage at 12.6 volts, but under load voltage drops to zero. Cable clamps are tight. Sounds like a bad battery. Removed cables and noticed that the posts were black in color. Put battery tester directly on posts and retested, battery tests good! Cleaned up posts and clamps with wire brush and car starts right up.
Cougar 3: Engine cranks slowly. Put battery on tender for over night. Tried to start and solenoid clicks hard but engine won’t turn over. But regular charger on battery. Internal breaker in charger trips almost immediately as if battery is internally shorted. Removed cables to clean up clamps and posts. Battery shows low voltage, about 6 volts. Tests bad under load. But battery on 2 amp charge for several hours. Battery now shows good voltage and current under load. Connected positive post. Connected negative post which produced a big spark and a loud click from the starter. Cranks and fires right up. Apparently the starter solenoid had stuck in the engaged position. Incredibly it did not burn up the solenoid or the starter. This one will go on the 1 amp trickle charger and then on a tender.
Moral of the story. Always remove the cables from the battery for testing. Even clean looking posts can have too much resistance to flow current. A good battery tester can pay for itself if you have multiple batteries to deal with.