charging problem on 78 L82
Thread Starter
Heel & Toe
Joined: Oct 2001
Posts: 15
Likes: 0
From: Leesville La
charging problem on 78 L82
I have 13.6 volt charge with a/c and headlights when first cranked but after 3 or 4 minutes I show a discharge. Have had the gauge rebuilt, changed the alternator and battery, ran a new wire from the alt. to the battery and checked all the grounds I can find. Can the starter cause this draw when it gets hot? I can run either the a/c or the lights but not both. Anyone had this problem before? Thanks, Jim
Pro
Joined: Aug 1999
Posts: 749
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From: Perth,Western Australia,Australia
Re: charging problem on 78 L82 (Jimmy Shepherd)
What size alternator do you have?Does the charge light come on?
Sounds like an earthing problem or a current drain.You will need to check for amp drain with an inline meter at the battery.Let us know if you need more info on how to do this.
Neil.
Sounds like an earthing problem or a current drain.You will need to check for amp drain with an inline meter at the battery.Let us know if you need more info on how to do this.
Neil.
Thread Starter
Heel & Toe
Joined: Oct 2001
Posts: 15
Likes: 0
From: Leesville La
Re: charging problem on 78 L82 (Fleetwood)
The alternator is a 65 amp and is putting out all it can. The gen light works normally. To add more confusion, sometimes it wont make a sound when trying to crank it-not even a click though the battery is hot ! But it can be boosted off. I suppose the extra voltage makes the difference. Thats why I suspect the starter armature has a bad spot on it.
Thread Starter
Heel & Toe
Joined: Oct 2001
Posts: 15
Likes: 0
From: Leesville La
Re: charging problem on 78 L82 (LAvetteman)
The gauge shows a large discharge with ignition on-engine not running but picks up to almost 14 volts when cranked. It just wont hold it but a few minutes
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Re: charging problem on 78 L82 (Jimmy Shepherd)
:nono: Well 13.6V is showing good charge from alternator Jimmy. Then as battery charges up the voltage drops as normal/expected. Don’t get “Voltage” confused with “Current” here. That’s a “Voltmeter” on a ’78 and your alternator has a built in voltage regulator.
Now an “Ammeter” is a current meter and will show an increase in current flow as you turn on loads – lights, A/C, starter, etc.. If you were to install an ammeter it would only show the current amount for loads in series (wire in same circuit).
Okay this “hot start” problem is from that poor little solenoid mounted on the starter next to hot exhaust piping. Best fix here is a heat shield. The big blocks in ’74 had a good stock shield. And I like the one JC Whitney sells for $20 that contours with the starter shape. But first try removing the solenoid off the starter and cleaning the contacts/contactor ring inside – yes inside – the solenoid as they do get arced up. :yesnod:
[Modified by cardo0, 8:14 PM 10/24/2003]
Now an “Ammeter” is a current meter and will show an increase in current flow as you turn on loads – lights, A/C, starter, etc.. If you were to install an ammeter it would only show the current amount for loads in series (wire in same circuit).
Okay this “hot start” problem is from that poor little solenoid mounted on the starter next to hot exhaust piping. Best fix here is a heat shield. The big blocks in ’74 had a good stock shield. And I like the one JC Whitney sells for $20 that contours with the starter shape. But first try removing the solenoid off the starter and cleaning the contacts/contactor ring inside – yes inside – the solenoid as they do get arced up. :yesnod:
[Modified by cardo0, 8:14 PM 10/24/2003]
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Re: charging problem on 78 L82 (Jimmy Shepherd)
:bb A second look at your post I notice the statement you can’t run both the A/C and lights together. Well you gott’a big load electrical load somewhere. A/C compressor? Your starter is only a load when you turn the key to start. Lets not mix things up here. Unplug the wires on the A/C compressor and see how things run.
It’s just hard to tell what condition your wiring is in as mine had plenty of Bubba mods and heat treatments (yep gott’a new wire harness now).
But it does sound like you’ve got a high load (short to ground) somewhere. :eek:
It’s just hard to tell what condition your wiring is in as mine had plenty of Bubba mods and heat treatments (yep gott’a new wire harness now).
But it does sound like you’ve got a high load (short to ground) somewhere. :eek:
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