AL-Shark

I have been having some problems on my 83 928S US model due to the battery running down while driving. I have been reading up on the Delco CS130 replacment and decided to go for it.

I ordered a remanufactured alternator and pigtail from a rebuilder who advertises on Ebay. The alternator with a 2 year warranty and a pigtail was $70 shipped to my door.

I hooked up the new alternator like TooFast's post. My pigtail was a 4-wire S,F,L, and P. S hooked back to the battery terminal (monitors battery level), F (Field) not currently connected, L to the exciter circuit/gage wire, and P not connected. I initially had no charge coming from the alternator. After some checking with my multimeter, I found that my exciter circuit (wire from the gauge) was not getting any consistent power to the alternator to start the charging process. That was probably the problem with my Paris Rhone so I will clean it up and keep it on the shelf. I have some digging to do and researching the wiring diagram to find my problem.

In the mean time, I ran the exciter circuit (L on the wiring harness) and connected it to the ignition source for the coil. I ran it through a light bulb socket with a 5 watt bulb sort of like old chevy's with an idiot light. The light protects the coil circuit from being ground by the alternator if the alternator fails and it gives me a test light to see if my alternator is charging. Now, the light ignites when I turn the key and goes out once the alternator starts the charging process (immediately). Once I run down my problem with original exciter circuit, I will switch it back to the original wire.

I am getting nice steady readings at my jumper terminal of over 14 volts and it stayed above 12.5 with everything in the car on high and my new electric cooling fan kicked in. Thanks to Sharkskin, TooFast and 928 Fixer for the informational write-ups! I am hoping to have everything travel ready for SITM in June.

SharkSkin

Cool! Glad to hear it worked out. That's at least 3 successful CS130 installs!

fbarnhill

Hi Guys,
I am considering this mod also. My 79 Euro charging system is really erratic. Sometimes it looks great and other times it barely shows up on the gauge at all. The lites are somewhat dim in the evenings etc... So, I am going to take the last weekend in April to do the TB/WP and vacuum lines. I thought I might squeeze in the alternator as well. Any warnings or suggestions of what to look out for?

Thanks,
Frank Barnhill

dr bob

Frank--

The wirng and stuff will be a bit easier to access once that alternator/PS pump console is unbolted and rolled forward a bit. You'll already have the battery disconnected, belts off, etc, so you are choosing a good time. It's also a great time to take a lot of pictures of the installation as you are doing it, with notes about each step. Plenty of folks are suffereing with early P-R alternators, I'm sure.

Be aware also that the excitation on the early cars needs a bit of an update, with a resistor change on the instrument cluster. I'd also make it a point to clean the pod connections and the grounds for the pod and the alternator before you take anything apart for the TB job. Often the 'low charge at night' symptom is related to pod grounds, where a poor ground raises the potential on the low side of the volt gauge. Makes it read low even when it isn't.

A good DMM will confirm your charging system condition, light on or lights off. I guess I'd start immediately with that step before I started tearing anything apart. It will help you figure out which are "problems" and which are "symptoms".

AL-Shark

Frank,
You are cutting it close for SITM. This would be a good episode on American Hot Rod; TB/WP, vaccum lines, and alternator with 6 days to go! Hopefully it will be a breeze. Check out the posts for the C130 on this forum.

My alternator came with a six-rib pulley and my stock belt was a 4 rib. I went ahead and used the 6-rib pulley because the rib dimensions are the same (I just have two extra grooves on the inside of the alternator pulley. The belt tracks fine. I am sure you could swap the pulley if you are so inclined.

Good Luck

fbarnhill

Thanks Guys,

I didn't realize that SITM was getting so close. With my luck, something will screw up and I won't make it. I think I am just goint to do the TB/WP and maybe the vacuum lines. Dr. Bob, thank you for your suggestions. I will do that right away. Who knows, maybe I won't need it after all. This car is very low milage and the usual things seem to be in amazingly good shape. Even the TB looks new but I can't verify it so I am going to change it anyway. That way I will know.

Thanks again and I will not have very far to drive for SITM.
Frank Barnhill
79 Euro

SharkSkin

BTW, it seems that the very early cars may not always need a resistor. There was a larger bulb used on the early cars in the exciter circuit. With a 3W bulb in there the original alternator charges fine, but with the smaller bulb used on the later cars(80+, I'm guessing) the resistor becomes more important.

dfroelicher

Just like Al-Shark I have an 83 928S and am considering the CS130 upgrade from the stock alternator. I have an issue with the entire car seeming to lag when it is night and even a little during the day.

Recently my interior dash lights (not the door lights) have gone out (different problem, my fault) and they have been replaced with two blue laser leds from checker with the ghetto lighter socket hook up. It seems that at night even just the two leds drop the volt gauge down at least a volt, I would like to remedy this and add the carputer that r-kraft is working on (check thread "holy s*#$!! What a great mfd idea"), hopefully this project will be what the doctor ordered and I can post some cool pics of the whole setup and finished product.

toofast928

AL-Shark,
Have you driven at night yet? You'll be amazed at how bright the dash pod is. And to think, I was considering LED conversion.
Good time to clean all the grounds so you can use the full potential of the 14.5V.

SharkSkin

df, sounds like your alternator may not be charging. What's your actual battery voltage at rest and when running?

Mark

I think he meant to say 6 WEEKS...not 6 days...

AL-Shark

No, I meant 6-days.

Franks says in his post he will be doing it the last weekend in April I thought he was waiting till the last weekend in May. 6 weeks should be plenty of time.

dfroelicher

I have never actualy tested the running voltage of the battery but with the car off the battery reads 11.8 so it is getting juice it just does not get enough when the car is stopped with all the stuff on.