77 f100 battery problem

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Nov 2, 2009 | 05:08 PM

77f100guy

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77 f100 battery problem

the truck sits with the cable off of the battery terminals whenever im not trying to start it, the thing is when is connect the cable and try to start it tries to start but after a second or two is sounds as though its loosing power and wont turn over anymore, ive replaced a lot but not everything, things i have replace, battery cables, starter selionoid , ignition coil, plugs & wires, voltage regulator, when i got the truck they guy told me it was having this problem but told me a voltage regulator would fix the problem, after installing a new one it still had the same problem. any ideas?

Nov 2, 2009 | 05:22 PM

montana_highboy

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From: Big Sky Country

How old is the battery? is it fully charged (12.6v)?

Nov 2, 2009 | 05:36 PM

77f100guy

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battery was brand new i bought it this time last year and it just been sitting

Nov 2, 2009 | 09:00 PM

fmc400

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From: Austin, TX

It doesn't matter if it's "brand new," you're going to need to check the voltage when you try to start it, and after it slows down.

Nov 2, 2009 | 09:11 PM

g0dl355

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If it's been sitting a year..where has it been sitting? In the truck?

Throw a trickle charger on the battery and then try to start your truck.

Nov 3, 2009 | 08:09 AM

Capitlj

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From: Fargo North Dakota

^ sounds like the battery is weak to me, might just need a charge.

Nov 3, 2009 | 09:07 AM

1975Ford

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Have you tried starting with some booster cables? does the truck start?

When the truck starts, what is the voltage reading (using a voltage meter) of the battery/ charging system?
The voltage reading of charging system should read above 13.5 volts with engine running.

Recharge battery, do not overcharge, then give the battery a battery test.
Most Autopart store will do this for free, call the nearest part store or your auto part store and ask them if they would give your battery a charge & battery test.
The battery should hold above 10 volts, in battery test mode, for at least 10 seconds.