93 lincoln mark viii wont turn over good battery and alternator HELP!!!

[Brian71]

i have a 93 lincoln mark viii that wont turn over at all unless jump started. The battery and alternator were both checked and both are working fine. After being driven (no matter how long) approximately 15 to 30 mins of sitting off the car needs to be jumped again. I'm at a loss please help.

 

[chris2523]

cape coral eh? i've been there.

battery terminal connections prolly. clean them thoroughly. maybe replace them. the stock style clamp on things suck.

also, swap in a known good battery to see if it makes any difference.

then, put a voltmeter on it while running. you better see at least 13. 14-14.4 is ideal.

 

[My Great 8]

+1 on the battery terminals. Welcome to LVC!!

 

[NetKeym]

Did you use these?

A 2008 Chevy came in the shop the other day with the same problem; it took me 5 minutes to figure it out. Those pretty red and black colored clamps shown below.

He had put new terminals on the battery, but the cables had bolt-on tabs, so he bolted them to the clamp bolts on the battery. Turns out that red and black paint makes a good insulator.

He had 13 volts across the posts, but if you touched the BOLTS on the terminal clamps, only got 9 volts. I just took the terminals off, went to the bench grinder and wire-wheeled the paint off the wire end. Voila, car started perfect.

 

[LaserSVT]

Sell it and by an LS.