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Car Eating Alternators....

Posted By: BAM

Car Eating Alternators.... - 07/01/10 12:52 AM

Folks,

66 Satellite with 68 440 Fury engine, MSD ignition with MSD distributor....third unit has died since October....2 were Napa, one was Autozone supplied...tension good, no squealing....coming back from 150 mile trip Sunday, dang thing dies with 30 miles to go....

Any ideas of the cause?????

Thanks, BAMMER
Posted By: ahy

Re: Car Eating Alternators.... - 07/01/10 01:25 AM

A guess... and some questions. 3 alternators from 2 vendors strongly suggests something amiss in the car's wiring or VR. Its possible the alternator is running at excessive voltage to overcome a weak connection in the main charge wires. I'd trace and inspect the wiring and connections from the alternator output stud to the bulkhead connector and bulkhead connector to the battery. Check the fusible links too. Pull the bulkhead connector and check for damaged terminals. Check the ammeter terminals for signs of corrosion or loose connections.

One way to check is to put a new alternator in and use a meter to check voltage at the alternator stud and the starter relay stud with the engine running at fast idle. At the starter relay stud, you should see 13-14 volts and about one volt higher at the alternator. If the alternator is lots higher, you have a weak connection or wire in the system.

Now questions. Does it fail by simply stopping charge? Any signs of bearing distress like noise? Have you had any of your failed alternators tested? Some parts stores will do this for free. If so what did they tell you? Did you replace the voltage regulator with the alternator?
Posted By: denfireguy

Re: Car Eating Alternators.... - 07/01/10 02:30 AM

I rebuild my own alternators and have for 30 years for that very reason. The rebuilds at the chain stores have always been poor. They have one moving part, 4 wear items yet they all seem to be a pain for rebuilding companies to figure out.
Nothing in your list of items draw a lot of current. I bet there is nothing wrong, just a run of bad alternators.

Craig
Posted By: 451Mopar

Re: Car Eating Alternators.... - 07/01/10 03:48 AM

What is failing on the alternator?
Windings, Brushes, or Diodes?
Which alternator is it, the stock 1968 type with the single wire to the field brush, or the newer style with two connections to the field brushes?
What is the maximum RPM the alternator is seeing (max engine RPM x Pulley ratio?)
Posted By: Ronnman

Re: Car Eating Alternators.... - 07/01/10 04:11 PM

I went through 4 alternators at two parts store, NAPA and O-Reillys. Two made noise when rotated on the counter and the other two would not rotate without hitting something inside. Whatever companies are doing their rebuilding needs a lesson or two. They even visually looked crappy. Finally got one from Autozone that was OK.
Ron
Posted By: Dragula

Re: Car Eating Alternators.... - 07/01/10 06:24 PM

Quote:

Folks,

66 Satellite with 68 440 Fury engine, MSD ignition with MSD distributor....third unit has died since October....2 were Napa, one was Autozone supplied...tension good, no squealing....coming back from 150 mile trip Sunday, dang thing dies with 30 miles to go....

Any ideas of the cause?????

Thanks, BAMMER




Typically the Chrysler alternators will not handle high loads over time well and most of all, they hate high rpm blasts thru the gears. The windings always come loose and they make a mess from there.

Best thing you can do is convert over to the newer style from Mancini. Burn outs and hole-shots killed more than a few of mine on the street, and at the track, if the belt stayed on, the pulley would blow right off.

Its one of the few parts on a Chrysler that are complete junk. Sorry, but I have switched both cars over to after market set-ups and even bought a spare for the Hemi, and after 7 yrs, I still haven't used it. One has a Mancini set-up and the other is custom set-up with a cheppy alternator.
Posted By: rockerbob

Re: Car Eating Alternators.... - 07/01/10 11:53 PM

I'm having the same problem with my 69 Satellite bracket car. I go through an alternator each year. Just last August now this past weekend. On my car its shorting out & draining the battery between rounds. I talked with the guy at the parts store I mostly deal with & he said in discust that the problem is Chinese rebuilds. He says they are junk. He pulled two from the shelf to test & both where bad. One had a broken terminal stud on the back. I too thought about updating to the newer style alternator. However I have read on here that the wiring needs to be updated to handle the amprage. So I guesss I will just have to carry a new spare with me.
Posted By: Dragula

Re: Car Eating Alternators.... - 07/02/10 12:17 AM

The mancini comes with the wiring diagram, and it eliminates the voltage regulator.
Posted By: 540challenger

Re: Car Eating Alternators.... - 07/02/10 12:33 AM

Quote:

I'm having the same problem with my 69 Satellite bracket car. I go through an alternator each year. Just last August now this past weekend. On my car its shorting out & draining the battery between rounds. I talked with the guy at the parts store I mostly deal with & he said in discust that the problem is Chinese rebuilds. He says they are junk. He pulled two from the shelf to test & both where bad. One had a broken terminal stud on the back. I too thought about updating to the newer style alternator. However I have read on here that the wiring needs to be updated to handle the amprage. So I guesss I will just have to carry a new spare with me.




I think you hit the nail on the head with this post. Given the age of the mopar alternators, lack of quality parts, and lack of quality rebuilders out there. i brought my Alternator to a local rebuilder who bee in the business for a long time. And discussed the issues wth almost all rebuild and i had them rebuild my alternator it cost around 250.00 and i have had zero problems since and my alternator been through hell from my 408.
Posted By: 68 R/T

Re: Car Eating Alternators.... - 07/02/10 12:47 AM

Which one that mancini has that eleminates the regulator. How many amps is it. Is it round or square back??/
Posted By: rockerbob

Re: Car Eating Alternators.... - 07/02/10 02:07 AM

Quote:

Which one that mancini has that eleminates the regulator. How many amps is it. Is it round or square back??/




I think he is refering to the new Nippondenso style that is common on the Magnum engines & new vehicles. Manici sell a retro-fit. I was not aware it comes with a wiring diagram. Still I have heard & read of folks who switched to this style without going to a larger wire had serious issues. I'm open to any sugestions to prevent this.
Posted By: 68 R/T

Re: Car Eating Alternators.... - 07/02/10 02:12 AM

We'll what is the biggest alt. that you should run with only a fuel pump, elect. fan and big fan nthat draws 60amp on start and 45 running
Posted By: ahy

Re: Car Eating Alternators.... - 07/02/10 02:16 AM

As posted above it could be 3 bad alternators in a row. Plus there is benefit to upgrading to a newer alternator. Still, there should be more diagnosis. Why did they fail? Try to get them tested and check your wiring! Even if you don't find much, its time well spent on an older car.
Posted By: BAM

Re: Car Eating Alternators.... - 07/04/10 03:36 PM

Thanks all for the replies (been outta town)....I actually spent the whole winter rewiring the engine compartment and power thru the dash...I have a technical background and made sure I did it right....I will have the alternators checked out, I really think I am getting crap, heck, I got one from NAPA before this that was dead on arrival, no output. I am gonna check into Mancini...i think I am getting what I paid for with a 45 dollar unit!!!!!

Thanks again
Posted By: The Sphinx

Re: Car Eating Alternators.... - 07/04/10 04:36 PM

I had a similar issue, tuned out the alternator field wire at the harness disconnect (by the right rear of valvecover) was partly popped out of the connector and grounding out on the block.
Posted By: rockerbob

Re: Car Eating Alternators.... - 07/04/10 11:08 PM

Saturday I went looking for a replacement alternator. I went to the parts store with the bad alt. & reciept in hand. They checked it & it was bad. Didn't have an other. Called a nearby sister store & they had one. Drove over. Had them check the new one & it was bad. They called another sister store. They had one & checked it before I drove over. It was good. So for now my car is working again. Think I will buy a spare so I can fix it at the track if need be.
Posted By: ahy

Re: Car Eating Alternators.... - 07/05/10 01:29 AM

Wow... lots of bad reman alternators getting sold (and returned). I hope the chain parts stores wake up and find better rebuilders. If I need a square back some day I think I will go the Powermaster/Mancini route.
Posted By: rexus31

Re: Car Eating Alternators.... - 07/05/10 01:04 PM

I recently had a similar issue with my freshly restored '65 300 'vert. The Alternator would not charge. I went through 3 alternators as the tester at O'Reilly's was not working. When the third wouldn't charge I took it to Autozone for a test assuming I would have to get my money back from O'Reilly's and purchase a new one from Autozone. They put it on the tester and it passed. I then changed the VR with a known working unit, no dice. I checked all the voltages with the key in the On position and the ignition wire disconnected from the Ballast and all the voltages were within spec. I was at a loss. I disconnected the Field wire at the Alternator and VR and attached a wire to the two external from the harness. I fired it up and the Alternator charged. Long story short, my brand new Bill Evans Engine Harness had a poor connection at the Alternator side of the Field wire. After removing the black plastic shield, I saw the connector was primarily crimped to the wire jacked and wasn't making a good connection with the bare wire. I installed a new connector and all is good. Don't discount the harness.
Posted By: BAM

Re: Car Eating Alternators.... - 07/05/10 10:46 PM

Thanks for all the replies.....yanked out the alternator today and the dang field connector shows a short to the alternator casing which of course grounds it when installed.....tok out the field connector and the metal inside is grounded.....took out my last bad unit from Autozone and the 12v OUTPUT lug is shorted to the casing.....I can't win......going to Mancini....

BAMMER
Posted By: Bob's71R/T

Re: Car Eating Alternators.... - 07/07/10 12:17 AM

THANK YOU ...4 posting this...my 71 challenger eats 1 a year pretty much to the day so at least now i know when i have 2 take it back 2 auto zone....just goes 2 show you i live 20 minutes away from MANCINIS..and i wish i'd known about the alternator problems as far as defective..thanks MOPARTS...and fellow Mopar addicts..
Posted By: GG1charger67

Re: Car Eating Alternators.... - 07/07/10 08:33 PM

I do a lot of reading on this and other forums and see the same common problems concerning starters and alternators,a lot of problems with parts store units and some problems just being mis-diagnoised.Next time you have a starting or charging problem,pick up your phone book or ask around for a good alternator and starter shop.Most every town and city has a few and most rebuilders cut thier teeth on these older chrysler alternator.They can sometimes save you money and time by properly diagnosising your problem and,or repairing your unit. Jason
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