Dkrone

i have a 72 cutlass, and i have had some electrical problems. i have replaced the battery the voltage regulator and the alternator, i used to have a regulator that always hummed but i found out it was due to a bad ground and that is fixed but now when i turn the car off the generator light comes on?? can someone please let me know what they think about this? thanks

ThyPlumber

Had the same problem with one of my cars, the previous owner had hacked the electric system pretty bad. After wasting a lot of time trying to figure out what was what, I decided to order new wire harneses, it was actually simple plug and play to replace the three harneses every thing worked perfect after that.

rocketraider

Light on with ignition off usually means a diode has shorted in the alternator. A good electrical shop can fix this in no time, and I lean toward having the existing stuff rebuilt instead of parts store replacements.

If it's not a 442, you did get an external regulated alternator? Parts monkeys have been known to give out the wrong one.

Dkrone

ya its just a cutlass s so i got the external regulated alternator, and i am wondering that both of you all could be right becuase the guy that had it before me hacked with all the electrical too and did a very poor job, but i also think the local parts stores are giving me the wrong alternator or voltage regulator cause i bought both with a lifetime warranty and i have been up to get new ones and they have given me differant ones

mugzilla

Can you use an internal regulated alternator and bypass the exyernal unit ..?

Oldsmaniac

I think I had this problem once, I found that the fuse was removed from fuseblock for gen/alt. You may want to see if the fuse is good.

rocketraider

You can. Year One used to sell a regulator bypass harness that made it very simple. Pretty sure they and other resto supply companies still do.

Dkrone, look at the two-wire plug for your alternator. Does the plug look like II (external regulator), or -- (internal regulator)?

Very possible the PO hacked it and put an IR pigtail on the harness.

I recommend buying a factory chassis service manual. It will show you: wire color, wire routing, and a complete wiring diagram and troubleshooting section. The 1972 book also covers both the external (all except 442/Toronado) and internal (442/Toro) regulated charging systems. They're on ebay frequently and most old car literature dealers keep them in stock. I think 72 is available on CD, but I keep hearing the scan quality is not good, esp on wiring diagrams.

Doncha jest LOVE fixing Previous Owners' Stamp? Just be thankful it ain't as common on Oldsmobiles as it is on Chevrolets. I have hardly ever seen a midsize 64-77 Chevrolet that hasn't had some kind of wiring hack job inflicted. Most musclecar era cars suffered from it.

Dkrone

Does anyone know of a solid state electronic voltage regulator to replace the external coil type factory external regulator?

Yellowstatue

I use a Delco solid state reg # 1116378, it's the same regulator as in my GMC pickup, used with 60 amp and higher alternators, mounts in the same holes with longer screws and same plug, hard to find though...but on the other hand there is a direct replacement reg that is the same shape as your old one only flatter and very much lighter...just ask for a solid state reg...

Aron Nance

When you go to get the replacement voltage regulator/alternator/ANY PART for you Cutlass, go to a REPUTABLE PARTS HOUSE THAT HAS GOOD COUNTER PERSONNEL. That business (like a lot of other's) has really gone downhill, as far as knowledgable personnel; expecially the discount chains. If you find a good counter guy/gal, stick with 'em!