May 24th 15, 05:32 PM
On Saturday, August 26, 2000 at 8:06:40 PM UTC-5, Rick Potts wrote:
> I replaced the alternator in my Warrior (PA 28-151) this week and the
> prior problem (the alternator dropping offline periodically, up until
> the time it dropped offline and refused to come back on 200 miles from
> home) has been replaced by a new problem.
>
> The good news is the new alternator came online when I started the
> Warrior's engine this morning and, according to the ammeter, started
> producing electricity.
>
> The bad news is the ammeter needle then started to wiggle back and
> forth across the dial like a windshield wiper, from "0" on the left to
> about "30" on the right, about two times per second. Varying the
> engine speed didn't make a difference in how it behaved.
>
> I measured the battery voltage (at the cigarette outlet) and it
> remained steady at 14 to 15 volts. It didn't fluctuate at all, even
> though the ammeter needle was dancing all around.
>
> The Piper Service Manual's troubleshooting chart says that "excessive
> ammeter fluctuation" can be caused by a defective voltage regulator or
> excessive resistance in the field circuit. I hesitate to blame the
> voltage regulator when the voltage stays so steady, so is "excessive
> resistance" the likely culprit?
>
> For "excessive resistance" the manual recommends: "Check all
> connections and wire terminals in field circuit for deterioration such
> as loose binding posts, broken wire strands at terminals, etc..
> Tighten all connections and replace faulty terminals."
>
> I'm no expert at reading electrical diagrams, but it appears the
> "field circuit" would include the voltage regulator, the overvoltage
> relay and the alternator switch. The output side would include the
> ammeter and a large (6 gauge?) wire that runs to the battery
> contactor.
>
> The voltage regulator and the overvoltage relay are mounted up under
> the instrument panel, so getting to them won't be easy. The alternator
> switch, on the other hand, is quite easy to get to so I think I'll
> start there.
>
> Question: How is the split master switch mounted? Does the plastic
> cover piece come off the instrument panel with the switch mounting
> from the front? Or do I have to remove it from the rear somehow? I'd
> like to get in there to clean and tighten whatever connections are
> there.
>
> Or is the voltage regulator still a potential culprit?
>
> Thanks for any ideas!
>
>
>
>
>
> ------------------------------------
> Rick Potts Phoenix, Arizona
> N32334 PA 28-151 Warrior
> ------------------------------------
Had a puzzling week with a 1978 Warrior doing the same thing with Load meter, finally located a chafed Alternator output wire to Primer line which now all adds up.
> I replaced the alternator in my Warrior (PA 28-151) this week and the
> prior problem (the alternator dropping offline periodically, up until
> the time it dropped offline and refused to come back on 200 miles from
> home) has been replaced by a new problem.
>
> The good news is the new alternator came online when I started the
> Warrior's engine this morning and, according to the ammeter, started
> producing electricity.
>
> The bad news is the ammeter needle then started to wiggle back and
> forth across the dial like a windshield wiper, from "0" on the left to
> about "30" on the right, about two times per second. Varying the
> engine speed didn't make a difference in how it behaved.
>
> I measured the battery voltage (at the cigarette outlet) and it
> remained steady at 14 to 15 volts. It didn't fluctuate at all, even
> though the ammeter needle was dancing all around.
>
> The Piper Service Manual's troubleshooting chart says that "excessive
> ammeter fluctuation" can be caused by a defective voltage regulator or
> excessive resistance in the field circuit. I hesitate to blame the
> voltage regulator when the voltage stays so steady, so is "excessive
> resistance" the likely culprit?
>
> For "excessive resistance" the manual recommends: "Check all
> connections and wire terminals in field circuit for deterioration such
> as loose binding posts, broken wire strands at terminals, etc..
> Tighten all connections and replace faulty terminals."
>
> I'm no expert at reading electrical diagrams, but it appears the
> "field circuit" would include the voltage regulator, the overvoltage
> relay and the alternator switch. The output side would include the
> ammeter and a large (6 gauge?) wire that runs to the battery
> contactor.
>
> The voltage regulator and the overvoltage relay are mounted up under
> the instrument panel, so getting to them won't be easy. The alternator
> switch, on the other hand, is quite easy to get to so I think I'll
> start there.
>
> Question: How is the split master switch mounted? Does the plastic
> cover piece come off the instrument panel with the switch mounting
> from the front? Or do I have to remove it from the rear somehow? I'd
> like to get in there to clean and tighten whatever connections are
> there.
>
> Or is the voltage regulator still a potential culprit?
>
> Thanks for any ideas!
>
>
>
>
>
> ------------------------------------
> Rick Potts Phoenix, Arizona
> N32334 PA 28-151 Warrior
> ------------------------------------
Had a puzzling week with a 1978 Warrior doing the same thing with Load meter, finally located a chafed Alternator output wire to Primer line which now all adds up.