Bought a '88 P72

[85crownHPP]

Well i just checked it, and sure enough its a draw from the alternator...
It was charging 13.3 when the 1st battery died, I thought that could be better. The only time i drove it at night like this it was quick and rainy so I may not have noticed the headlights acting funny. i did feel like there was some extra noise coming from under the hood reminiscent of 'bad-out-of-the-box' alternators Ive installed.
Time for a forced upgrade! I noticed this thing uses a weird blend of 1G wiring and fire hazard wiring, particularly the push-in spade connection for the charge wires near the air box. It will be good to get rid off all that and the regulator/wiring...

Im heading to the pick n save for a big 3G or a little 3G and some brackets, and another Explorer charge wire.

Oh yeah, all this time I've been forgetting to mention that the AMP warning light never comes on, even with the motor off and key on. Could this be part of 'dark mode'? The engine and seat belt lights do come on though...
I noticed this when I bought it and just made sure it was charging, never thought about looking into it again.

[gadget73]

no idea if it was standard on all 351s. here, only the police cars got a 351, and the police package included the 100 amp alternator.

Testing the draw is easy if you have an ammeter. Just hook it up, and then pull the wire off the alternator to see if it changes. I'd expect the alternator to feel a little warm if the diode is shorted though. I'd also figure you'd see lower than normal charge voltage, or at least a wierd ripple that would probably show up with pulsing headlights or a dancing voltmeter.

[johnunit]

did all 351s (as in, canadian 351s) get the bigger alternator, or just you fancy-shmancy cop car owners?

[85crownHPP]

Almost, they are larger versions of the externally regulated (1G) alts, also found in boxes with the front windshield defrost grid. A 3G for this would mean I'd get to clean up lots of mess...
Damn rain... I might get to mess with it tomorrow. At least I got the batteries charged back up.

[1990LTD]

It's probably one of those fancy police alternators, me thinks..

I thought they were just bigger versions of the firetrap alternators?

[87gtVIC]

oh yeah.That totally slipped my mind.

[Grand Marquis GT]

It's probably one of those fancy police alternators, me thinks..

[87gtVIC]

I have heard multiple people complain about deadbeat alternators as the root of constant battery drain, so swapping to a 3g is not a bad idea anyway. Consider swapping one of your other cars alternators (assuming that your 91 is non 3g) into this one and see the results?

[85crownHPP]

I'm open to trades!

But first I need to fix this bad parasitic draw that just popped up... I killed two batteries in about 6 hours last night... thank goodness I have 3 vehicles Otherwise I would have had to hijack the roommate's Exploder to go to work this morning... he doesn't get up till lunchtime anyway.
I thought it was the cig lighter shorting out because I tried to use it for the 1st time yesterday and it never popped back out. I did pull the lighter back out but I figured it may be defective inside. Sure enough the socket was hot (was getting current) so i unplugged it, but I still woke up to a dead battery after letting it run for about half an hour last night.

How common is a bad alternator diode guilty of a draw?
I'm going to investigate tonight if the weather stays dry. Might be time for a 3G for this thing...

[RustyRodder]

nice!


.....trade?

[moneypit]

God I'd love to have that car... Trade you a fixed-up Isuzu pickup!

[1987cp]

Looking very good! I dig the '98 centercaps on 15" wheels.

[87gtVIC]

Looking good!

[85crownHPP]

Got a good axle and bearing in today finally! tech thread here
It's snowing and wet here so I haven't been able to double check to see if I've dun' good or not.
I also put the p71 caps on it, mmmmm....! I drove it around for about an hour today, still running well! It feels peppier than the 91. I'm thinking of using it as the winter snow mobile... its got the best tires for snow and i could keep the trunk full of wood. If it does well, may have to put the good door panel parts on and detail the inside a little. Those bucket seats sure are cozy...

[85crownHPP]

Well i got a surprise day off work today... I went strait to the pick n save and got two beautiful axles of the right length (one spare for the 85) just in time to beat the cold rain. I'd be fixing her up right now, but a co-worker tells me that the auxiliary bay is currently in use for a timing belt / water pump job.... he'd better not be bullshitting me!!!