Thread: Charging woes
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Dave at Pelican Parts Dave at Pelican Parts is offline
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Location: Silly-Con Valley
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The voltmeter you use for the computer stuff should be fine, as long as it has a 0-20VDC range. An automotive electrical system runs on "12 volts" (more like 14V in practice), so you need something that can measure that range.

As for how, just poke one probe of the voltmeter onto the + post of the battery, and the other onto the - post. With the engine off, a fully charged battery should show about 12.6V. With the engine running, you should see between 13.5 and 14.5V unless the electrical system is heavily loaded (lights, etc.).

One of the plastic covers is shown in Haynes, Fig. 1.14 "Fan, fan casing and associated parts" (p. 22 in my copy). It's part #1 in that diagram. The other cover is "around the corner" from there, on the side part of the engine tin.

A really bad alternator might cause some running problems, but my car (when it still had points) ran just fine until the system voltage dropped below about 9V--which is really dead. The alternator had failed, and I had to jumpstart the car and drive ~45 minutes home because the battery was completely flat. I made it to within a few blocks--I had to stop at a red light, and the draw from the brake lights was enough to drop the system voltage below the point where the injection worked. Apart from having the motor cut out when I used the turn signals (same problem), no driveability problems on the way home until then.

So I doubt the alternator is your running problem, though it is possible.

If you run the engine with the battery disconnected, you risk blowing some of the diodes in the alternator and possibly damaging some of the other electrical parts in the car. That is not recommended procedure....

Pelican Parts 914 Tech Support

A few pics of my car:
Old 07-19-2005, 05:23 PM
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