My 65 was dead the other day when I tried to start it. I recharged the battery and started the car fine. While idleing with no accessories there is a slight negative charge. With throttle there is a slight positive charge. When I run headlights idleing there is a huge negative charge and while around under normal throttle I can barely keep it at a positive charge. Alternator going bad? I tried tightening the alternator and it made a very slight difference, but not much. Should I try to replace it? And if I do what do I check to make sure it is not orig so as not to use an orig alternator for turn in? THanks!

Mike

 

You can have alternators rebuilt, open the phone book in you area, and look under auto electric.

Might be a voltage regulator as well.


Mark

 

Find a shop that can check the voltage regulator settings and while there at it they should be able to check output from alternator too.

 

Alt's arn't hard to rebuild--last one cost me 12 bucks for parts at NAPA tho it didn't need bearings but they cannot be to spendy??

 

I never thought of doing it myself.. I figure it can't be nearly as complicated as a carb anyways ...I'll see if there is a kit avail and give it a whirl.

On a side note, they seemed to have designed this car to put things in the most diffucult places possible... Hardest voltage regulator to get off EVER.

 

'Well Nuts" gone? Sounds like Bubba replaced them with regular nuts.

 

Mike email Garner, He has a guy in Goldsboro that rebuilds alts.... He's on an odd shift right now so be patient.... Dave...

 

I have mentioned this on the forum quite a few times. If you plan on working on your own car you need to have some tools and one of them you need to have is worth its weight in gold. You should look into a Milton#1260 Battery and Charging Testor. It is a Chrome handheld testor that won't let you make a mistake. I have depended on mine for years and it paid for itself 100's of times. No guessing on whether a battery is good or not. No throwing away or trading in a perfectly good battery for nothing and finding out a week later you made a mistake by replacing the battery and not looking elsewhere for your problem. Two battery clamps is all that is needed to be hooked up. With the tester you are able to do a load test to your battery to see if it is up to snuff. With the car running it tells you exactly what your alternator and regulator is putting back into your battery. In your case by what I have read tells me it is either the alternator or regulator. I am almost willing to bet your regulator is going bad. It is the cheapest of the two so you might want to start there and put a new one in the car and see if you notice a difference. I have a new electronic regulator in my C-2. I think they are more reliable then the old point type regulator that came from the factory. With the Milton testor you would know right away.

Fred

 

And you can get a bolt in electronic replacement for your regulator for under $20 with a warranty at your local FLAPS. Put your old original in a box and save it for whenever.

 

Well prior to reading this I had the alternator checked and was told the alternator.. so I replaced it. Everything is the same as before.. actually a little more of a negative charge at idle now. I have a new electronic regulator, but for the life of me cannot get it off. I have even used air tools and no go. I have positive control of the nut and bolt on both sides, but one just DOES NOT want to come off. It simply spins there like the threas on the nut/bolt are stripped. I am almost down to cutting the thing off if I could guarantee I would not damage my paint

 

Well I finally got that bolt off and installed the new regulator. Now when the car is off I get indications of a draw on the gauge og a draw when I use something like brake lights. When I start the car it reads the same, and NOW when I give it gas and try to manipulate the charge there is no movement.

Another question is... is the voltage regulator supposed to be insulated from the core support? On 2 of the three bolts there was a rubber spacer which looked home made.. are those supposed to be there or not? Or does it matter?

 

Ok.. after replacing the alternator and regulator I can now never get a positive indication on the ammeter.. what did I do? I have replaced these items before and it was straight forward..

 

Go out and get that Milton #1260 like I suggested to you earlier. You can even go to Harbor Freight and get a Chineze knock off of the Milton Testor for under $20. I saw one and it almost looks exactly like the Milton but it is not chromed but no big deal. Don't depend totally on what you see on your cars ammeter the Milton or similar tool will be exact to the point as far as how much your system charge is being put back into the battery. By the way there is not a rubber insulator under the regulator from the factory. Make sure your regulator is grounded. Don't forget it is sitting on fiberglass. Make sure the groundwire is hooked up to one of the mounting bolts. Who ever checked your alternator out doesn't seem to me like he knew what he was doing. They might of just guessed that it was bad and didn't realize that your system has an external regulator that could of been the problem. Newer GM vehicles from 71' on up had internal regulators so most of the time the problem was usually taken care of by replacing the alternator in those cars or the battery when there was a problem with charging. One other word of advice. When installing a electronic regulator don't just plug it into the harness of a car without grounding it or most of the times you will short the regulator out. Being in the auto parts business I have seen many of Ford electronic external regulators go bad right from the get go from people not making sure it was grounded when testing it. I say Ford because like Chrysler they continued using external electronic regulators into the 90's unlike GM who gave it up in 71' like I stated earlier.

 

There are rubber isolators (Well-nuts) on the three voltage regulator attachments to the inner fender, for vibration; the inner fender is fiberglass, so the VR is grounded separately - there's a separate black ground jumper wire that's screwed to the VR base at one end, and goes under the attaching screw for the horn relay to the radiator support at the other end (the radiator support is the ground). There's also a larger black wire coming out of the harness near the horn relay, and its ring terminal also goes under the horn relay attaching screw - that one grounds the alternator to the voltage regulator. If both of those grounds aren't in place under the horn relay attaching screw, the voltage regulator won't work and the alternator won't charge.

See Section 6, Sheet B4 in the Assembly Manual for the short separate ground jumper wire, and Section 12, Sheet A8, View "A" for the large ground wire from the harness.

 

Thanks John for letting me know that there is suppose to be factory rubber insulators under the regulator of a C-2, my 67' doesn't have them and I assumed there wasn't any. I haven't owned another C-2 since 35 years ago and I guess somehow they disappeared on the one I currently own. I guess I gave the wrong info to Corvette forum member (mikeyandem1) sorry. The rest of the info I gave should help him out though.