alternator diagnosis

[lukerman]

Okay guys, I have been through the discussions and want to clarify the real problem with the alternator. It seems that the voltage regulator is the apparent problem reading the previous advice.
Here is what is happening with my 86. until I rev up my car, the lights and blower motor run low, then when It gets 2-3000 rpms, everything runs normal at full power. The biggest problem with this is that until I rev it up or get up to speed which raises the rpm's, the car drains the battery power, and if I stop somewhere within that time, the car will not start.
my question is will a new voltage regulator fix this issue?

any advice will surely be appreciated.

you guys have been so helpful in the past and saved my 86 from burning when u told me to replace the fuel lines when I had no clue to check them when I bought it. a, I will never forget your time and if you ever come to st Louis area, I will return the favor with a meal or a place to lay your head.

[uBoat Commander]

Cheaper / easier / better long-term to get an AC Delco Reman 90AMP Alternator - comes with regulator, under $100

[lukerman]

u got a part number or local place to purchase. oriellys sell crap brand. lol

[uBoat Commander]

AC Delco Reman (90Amp Upgrade) ********.com. I swear by them for every make of part, I get the stuff the next day at a lower cost & higher quality than local stores

[hbueno]

If you're talking about the AC Delco CS130, that fits the 16V cars. Not sure what fits the 32V cars.

Hugo

[Landseer]

There is a small exciter wire that runs from the dash to CE panel, through the 14 pin connector in the engine compartment, on to the alternator within a harness. That wire carries a bit of current so-as to excite the alternator at idle RPM. I'd begin by checking that wire for continuity along its route.

The alternator will usually self-excite at moderate RPM even if the wire isn't intact.

It is also possible the alternator brushes are about worn-out and its the motor vibration that is causing them to contact the spinning shaft. I've had one like that on an 86 car. It progressed to not kicking in at all, unless tapped with a hammer.

When the 86, when driving it, isn't charging the battery, then the battery will eventually start to fade. The voltmeter moves slowly down towards 10V. Then the dash lights will all flash for a while, then the car dies. Wife and daughter had this happen on trip from our old home base in Richmond to VA Beach. Just made it to the destination when it shut down.

Solution was a new alternator. Due to timing, I had Advance Auto order a Bosch factory rebuilt Bosch unit. (comes in a Bosch box, if not, send it back!) Bosch rebuilds the wear parts of the alternator to a high standard. They had one in stock in their Roanoke warehouse, so I ordered it at 5 pm and picked it up at the store the next morning before 8.


The delco alternator for, say, an 88 camaro, rated at 105A, will substitute, with minor shimming of the mount, but only on the 16V cars. The 32V mount is much different.


JHowell on rennlist recently posted that a certain motorcraft unit, maybe from a ford contour, would work on later cars. Other than that, nobody else has found an aftermarket cross-swap.

The rebuilt Bosch is the answer for the 32V cars. But I think you may have a problem with your exciter wire.

[uBoat Commander]

For 32 valve? $180 for an AC Delco 115AMP at ********. These $300-$400 units are silly.

I'd bet $100 that the alternator he is having a problem with is a Bosch. I hate the alternators they make - the description of the problem above always happens in the German Cars. When I start my Vanagon, I have to rev it up or the battery will drain to dead with the engine running. But when I replaced with an A/C Delco, problem was solved.

[Fredfox]

Plus 1 on the Delco, The regulator is built in to the alternator therefore there is no need for the exciter wire. They do make a smaller one also.
I use them on everything, you can also get a low cut in regulator so it starts charging on startup and no need to hit the accelerator. Normally you need to hit the accelerator to get it to start charging and then it will stay charging till you shut it off no matter what the rpm.

[Landseer]

Originally Posted by uBoat Commander

For 32 valve? $180 for an AC Delco 115AMP at ********. These $300-$400 units are silly.

I'd bet $100 that the alternator he is having a problem with is a Bosch. I hate the alternators they make - the description of the problem above always happens in the German Cars. When I start my Vanagon, I have to rev it up or the battery will drain to dead with the engine running. But when I replaced with an A/C Delco, problem was solved.

The rebuilt Bosch was $155, though its been 3 years ago. It really is a great unit for the later cars. I've got 3 32V cars using this original equipment unit and they are great.

Delco doesn't have one for 32V. We've been through all the casting pictures in previous years, nada.


Rock Auto often has some bad listings because they don't cover every nook and cranny of the odd models.
A Delco will fit the 85/6 Euro which is 16V, maybe that's where they made the mistake.
(EDIT --- no, read closely the listing on Rock Auto. Its a AC Delco branded rebuilt Bosch. And AC Delco doesn't rebuild, they hire out. Run like the wind from these parts)

I've put them on the 16V cars with good results. That Paris Rhone OE alternator has some weaknesses.


The mounting difference by the way is not in the configuration of the block. The cast aluminum mount that holds the power steering pump also carries the alternator. It changed for 32 valve cars.


Back to the problem Lukerman is facing, sir, that exciter wire is notorious for failure in at least three different ways. Wire breaks inside insulation at alternator end; wire has bad connection inside un-serviced corroded 14 pin connector; wire is shorted to others within harness due to insulation breakdown in section that leads from 14 pin connector to alternator. Seen all three myself.

[Landseer]

Originally Posted by Fredfox

Plus 1 on the Delco, The regulator is built in to the alternator therefore there is no need for the exciter wire. They do make a smaller one also.
I use them on everything, you can also get a low cut in regulator so it starts charging on startup and no need to hit the accelerator. Normally you need to hit the accelerator to get it to start charging and then it will stay charging till you shut it off no matter what the rpm.

Need pictures of the Delco on your 86.5 Fred. Prove me wrong.

[lukerman]

this is my third alternator so I believe the exciter wire may be the problem, but I refuse to believe there is not a way to bypass this possible bad wire. Is there no way to "trick" the alternator by running another wire to it? how much power does this wire have?
again, thanks for the helpcar .
Yes, that is exactly what is happening to me that happened to your family. I can drive from st Louis to CA and no problem, but If I try to warm up the car by idling or sit at a long stoplight, the car sucks the power quickly from the battery.
there has to be a way to bypass.

[Crumpler]

You know I have seen my voltmeter creep down to 10V on extended highway use, now that you mention it.
I blew it off as a cluster gremlin, I guess it will look at that.

Lukerman, welcome to Pelican, there's a couple of us around in St. Louis.

[uBoat Commander]

Originally Posted by Landseer

The rebuilt Bosch was $155, though its been 3 years ago. It really is a great unit for the later cars. I've got 3 32V cars using this original equipment unit and they are great.

Delco doesn't have one for 32V. We've been through all the casting pictures in previous years, nada.


Rock Auto often has some bad listings because they don't cover every nook and cranny of the odd models.
A Delco will fit the 85/6 Euro which is 16V, maybe that's where they made the mistake.
(EDIT --- no, read closely the listing on Rock Auto. Its a AC Delco branded rebuilt Bosch. And AC Delco doesn't rebuild, they hire out. Run like the wind from these parts)

I.

I could not disagree more.

I get parts from rock auto no less than twice a week, and I have never received a part that does not fit. Only thing I ever got that was no good was a faulty Bosch O2 sensor, and they sent me a free one the next day when I told them. No hassles.

The alternator for a 32V sold on ******** is the correct alternator.

As for them not having the correct parts for "odd" model cars, they are my go-to source for my 1965 Nissan Patrol, and all of my old VW Vanagons & busses, as well as my Karman Coupe. Vehicle do not get more "odd" than this.

I have no affiliation with them other than being their #1 fan - they are an outstanding supplier.

[Alan in AZ]

So - simple question - does the charge light ever come on? in bulb test? when the alternator isn't generating?

If it never comes on the alternator is probably not the culprit (since we know it can generate).

In which case I think you need to fix it - its really not that hard - its just some work to track it all down.

Assuming the bulb doesn't ever work (my guess):

With the ignition on ground Pin L23 (blue wire) on the Central Electric panel bottom plug connectors - does the charge light come on then?

If no - you have a problem in the pod - possibly the charge bulb or its resistor.

If yes move to the 14 pin connector in the engine bay - unplug the engine side - ground the pin 1 (blue wire) on the car side - with ignition on does the charge light come on?

If yes - replug the 14 pin connector - ground the small terminal on the alternator (blue wire) - with ignition on does the charge light come on?

This will tell you what section the break is in - if thats what it is.

It will likely be in the section between the 14 pin connector and the alternator.

In fact its most likley to be in the final section where the alternator stressed it when it was left hanging from just this wire (been there - seen that many times). If so likely repair is to strip it back to find the break and attempt to splice it there. If its broken inside the loom you can try backtracking into the loom - or run an additional wire back to the 14 pin connector.

BTW these instructions are for an '86 - CE panel connections will vary by year.

Alan

[Landseer]

Originally Posted by uBoat Commander

I could not disagree more.

I get parts from rock auto no less than twice a week, and I have never received a part that does not fit. Only thing I ever got that was no good was a faulty Bosch O2 sensor, and they sent me a free one the next day when I told them. No hassles.

The alternator for a 32V sold on ******** is the correct alternator.

As for them not having the correct parts for "odd" model cars, they are my go-to source for my 1965 Nissan Patrol, and all of my old VW Vanagons & busses, as well as my Karman Coupe. Vehicle do not get more "odd" than this.

I have no affiliation with them other than being their #1 fan - they are an outstanding supplier.

Read the listings. Not a delco, there isn't one for the 32V

[Danglerb]

+1 What Alan said.

Alternators have improved since 1986. Surprisingly true, 28 years later technology has advanced some, and modern alternators, I think called Generation 6 or so, work better, have more output, smaller size etc. The issues with our cars are related to fit and cooling, not so much anything electrical.

Caveat, almost nothing that you change from stock won't have some unpredicted adverse quality.

[lukerman]

so I assume that if I buy that delco I will have to run a jumper wire from the battery cable connection on the alt to the plug in on the alt, correct?

[lukerman]

and you are correct, the ones I have bought are bosch

[Alan in AZ]

Just diagnose the one you have - there is probably nothing actually wrong with it

Alan

[lukerman]

thanks to everyone for the input. I will post how I attempted to fix it and the results as well if there is more than one attempt.
Thanks Again.