Correct voltage at battery @3000 rpm

[caproader]

Guys,

When I check the voltage at the batery terminals @ 3000 rpm, I am seeing 14.1 volts. Reseach on this board says that it should be less than 13.8v; anything higher suggest a bad regulator.

However, when I read the factory workshop manual, Section L, page 7 says that charging voltage @ 3000 rpm should be between 13.5 and 14.5v. The red light glows red until about 1200 rpm on the way up and comes back on around 1400 rpm as the engine slows down. Before I switched to an Optima battery, I did see some while powder in the battery boxes.

I took the cap off of the Marchal regulator and ran a strip of 800 black paper through the contact points.

1. Do I have a regulator problem?

2. Does the Marchal regulator have a voltage adjustment capability?

3. If I have a bad regulator, is there a source for a solid state regulator so I do not have to buy a new alternator with integrated regulator?

4. Are there any other questions I should be asking or test I should be doing?

Thanks.

John
73 2.7 mfi onelap car

[orange911]

You meet spec at 3000, but not below 1400 (light is on). Since the fast speed seems to be working, the regulator must be working (unless it failure is intermittent). Regulator regulates the voltage less than 14.5v and from going over. But since you are falling below 12v causing the light to shine, you probably have one of the following problems:
-belt slipping/worn
-pulling too much current for a weak battery (lights, fogs, defroster, etc..all running at once) but not likely with an optima
or
-the alternator brushes are worn - making contact, but maybe not on both sides.

For the belts, check the tension on the belt and make sure it is not slipping. If you have tension, check to see if the belt is worn or slick from oil.

Also, check your chassis ground at the motor/tranny.

This site may help:
http://www.pelicanparts.com/techarti...lt_replace.htm

[caproader]

Orange911

Thanks for the thoughts. You have given me something to do this week end. Not only thaty but the distraction in the garage may have even saved my fingers and toes from being blown off.

Most of the stuff I have done recently as I had the engine out of the car earlier this Spring. But I've been wrong before so this will give me some things to re-check. Thanks again

John