Charging system

[Mike1973]

1985 Chevy 1/2 ton 2wd 305 c.i.  So I had the whole experience of the alternator needing attention (dimming lights, slow cranking then finally failing to turn over.)  This was pretty text book so I thought.  I took the alternator in and had it rebuilt at my usual auto electric shop.  I then installed the alternator and at idle it still seemed to only charge at 10.8-12.5v.  Just to rule out anything I took the alternator back off and had it bench tested and it tested good of course.  The battery is a 3 year old Die Hard so I took it into sears and had them do a full charge and test the battery, it as well checked OK.  So I reinstalled the battery and of course it cranked fine and all the biz until it of course died due to poor charging.  So where am I at here?  What is my next step?  I'm a little stumped.  Thanks a million in advance for any help.

Mike

[gildardo01]

check your wire that goes from the battery to the alt... make sure all the wires and connections look ok.. sometimes the wire goes from alt to the starter then to the battery... something else you can do is temporary connect a wire from the BAT location on the alt to the battery ( use a wire 10ga  with two alligator clip) and see how that works..  another thing is that alternators need good ground so they charge property... though i dont think thats an issue because you stated to recently removed it so i assume its all clean...

[VileZambonie]

What did you pay to have it rebuilt and what exactly did they replace? Why didn't you just pick up a re-manufactured unit?

[Mike1973]

I paid $40 to have it rebuilt which is cheaper than a reman.  Everything was replaced internally. 

I will go over my wiring again and I'll try the jumper wire tip.  I keep everything in perfect working order on the truck and wires are in proper looms, not oily and basically in great mech. shape.

[Mike1973]

Let me ask this, what's the thought on the fusible links down by the starter?  If one or both are shot will I still show at least the low voltage that I'm getting?  I don't know...those fusible links throw me sometimes as far as does it bend super easy like it's blown.... 

[bake74]

     My sons 79 blazer just had a problem with the fuse able links at the starter.  He thought the starter went out, bought a new one but same problem.  When I got a chance to look at it, one of the fuse able links down at the starter the wire basically pulled out except 1 or 2 strands. 
     So we replaced both fuse able links and no more problem.
     But the problem was not a charging issue, it was a starting issue.  His battery never drained.

[bd]

1985 Chevy 1/2 ton 2wd 305 c.i.  So I had the whole experience of the alternator needing attention (dimming lights, slow cranking then finally failing to turn over.)  This was pretty text book so I thought.  I took the alternator in and had it rebuilt at my usual auto electric shop.  I then installed the alternator and at idle it still seemed to only charge at 10.8-12.5v.  Just to rule out anything I took the alternator back off and had it bench tested and it tested good of course.  The battery is a 3 year old Die Hard so I took it into sears and had them do a full charge and test the battery, it as well checked OK.  So I reinstalled the battery and of course it cranked fine and all the biz until it of course died due to poor charging.  So where am I at here?  What is my next step?  I'm a little stumped.  Thanks a million in advance for any help.

Mike

Let me ask this, what's the thought on the fusible links down by the starter?  If one or both are shot will I still show at least the low voltage that I'm getting?  I don't know...those fusible links throw me sometimes as far as does it bend super easy like it's blown.... 

Mike, do you have a voltmeter or are you relying on the dash volt gauge?  Do you know how to perform voltage drop tests?  Do as Gildardo suggested and check all of your charge harness connections.

[Mike1973]

BD, yep I've been using a digital volt gauge.  I'm out of town with work right now but when I get back mid-day tomorow I'm going to tackle it again.  I'm going to go over all the wiring closely.

[VileZambonie]

You can buy a cheap reman for $38 bucks from Autozone but cheaper isn't better. Get a quality reman unit. Just the diode trio and rectifier bridge would cost you $30 bucks. Another $10 bucks for brushes another $10 bucks for bearings etc. It's just not worth rebuilding them anymore.

I paid $40 to have it rebuilt which is cheaper than a reman.  Everything was replaced internally. 

I will go over my wiring again and I'll try the jumper wire tip.  I keep everything in perfect working order on the truck and wires are in proper looms, not oily and basically in great mech. shape.

[Irish_Alley]

a truck can run off 10 volts if thats what your alt was putting out with the headlights off

[Mike1973]

You can buy a cheap reman for $38 bucks from Autozone but cheaper isn't better. Get a quality reman unit. Just the diode trio and rectifier bridge would cost you $30 bucks. Another $10 bucks for brushes another $10 bucks for bearings etc. It's just not worth rebuilding them anymore.

I paid $40 to have it rebuilt which is cheaper than a reman.  Everything was replaced internally. 

I will go over my wiring again and I'll try the jumper wire tip.  I keep everything in perfect working order on the truck and wires are in proper looms, not oily and basically in great mech. shape.

Thanks Vile but right now my issue or problem is charging not if I should rebuild the alternator or by a reman. 

[VileZambonie]

You can buy a cheap reman for $38 bucks from Autozone but cheaper isn't better. Get a quality reman unit. Just the diode trio and rectifier bridge would cost you $30 bucks. Another $10 bucks for brushes another $10 bucks for bearings etc. It's just not worth rebuilding them anymore.

I paid $40 to have it rebuilt which is cheaper than a reman.  Everything was replaced internally. 

I will go over my wiring again and I'll try the jumper wire tip.  I keep everything in perfect working order on the truck and wires are in proper looms, not oily and basically in great mech. shape.

Thanks Vile but right now my issue or problem is charging not if I should rebuild the alternator or by a reman.

OK so why do you think I posted that? Do you really think you had all of your internal components replaced parts and labor for $40 bucks? Your problem sounds like the voltage regulator. Either take it back to him or replace it.

[gildardo01]

You can buy a cheap reman for $38 bucks from Autozone but cheaper isn't better. Get a quality reman unit. Just the diode trio and rectifier bridge would cost you $30 bucks. Another $10 bucks for brushes another $10 bucks for bearings etc. It's just not worth rebuilding them anymore.

I paid $40 to have it rebuilt which is cheaper than a reman.  Everything was replaced internally. 

I will go over my wiring again and I'll try the jumper wire tip.  I keep everything in perfect working order on the truck and wires are in proper looms, not oily and basically in great mech. shape.

Thanks Vile but right now my issue or problem is charging not if I should rebuild the alternator or by a reman.

OK so why do you think I posted that? Do you really think you had all of your internal components replaced parts and labor for $40 bucks? Your problem sounds like the voltage regulator. Either take it back to him or replace it.

true... test the alt with a multimeter... should be about 13 volts... definitely not 10 volts... if its not 13 then the alternator isn´t good... there should be a warranty with the alternator...

[Mike1973]

Vile, I did actually find my issue; it was a wire short.  Indeed, I did have the alt. rebuilt for $40 with all internals replaced.  I've known the guy who rebuilt it for 20 years, he's well know in the city I live in and has an impeccable reputation.  So....the issue was not an alternator half-a** job, it was a short. 

You can buy a cheap reman for $38 bucks from Autozone but cheaper isn't better. Get a quality reman unit. Just the diode trio and rectifier bridge would cost you $30 bucks. Another $10 bucks for brushes another $10 bucks for bearings etc. It's just not worth rebuilding them anymore.

I paid $40 to have it rebuilt which is cheaper than a reman.  Everything was replaced internally. 

I will go over my wiring again and I'll try the jumper wire tip.  I keep everything in perfect working order on the truck and wires are in proper looms, not oily and basically in great mech. shape.

Thanks Vile but right now my issue or problem is charging not if I should rebuild the alternator or by a reman.

OK so why do you think I posted that? Do you really think you had all of your internal components replaced parts and labor for $40 bucks? Your problem sounds like the voltage regulator. Either take it back to him or replace it.

true... test the alt with a multimeter... should be about 13 volts... definitely not 10 volts... if its not 13 then the alternator isn´t good... there should be a warranty with the alternator...

[bd]

Mike, thanks for posting the outcome.  For our edification, where was the short?