Howdy Morph,

When I rev it, it reads 13.8V at the battery. Does this sound normal ?

The alternator should be regulated to around 14.2V. But, 13.8V will recharge your battery. It will just take a bit longer to do it. Your alternator may need new brushes.

But that is not the primary problem. In your first post you said,

Battery discharges if it sits for a few days.

That is the problem you need to chase first. The clock and radio and maybe more circuits will pull current even when parked with the key out. The combined draw of all "keep alive" circuits measures a few milliamps; tiny current draw on a very deep well (the battery). The problem comes when some circuit begins to pull either more current than it should, or pulls current when it should not at all do so.

I am confident that disconnecting the battery at the terminal will allow the car to start just fine after sitting for a few days. That proves that something is pulling excessive current but it does not find the circuit that is responsible.

The first thing I would look for is a light staying on. In the glovebox, under the hood or in the trunk or even the dome light, though that should be obvious. How about added stuff? Have you got an alarm? Is there a custom sound system? Anything that was added to the electrical circuits are prime suspects. If you cannot find an obvious current draw, you have to look for the less obvious.

Your next check needs to be measurement of current draw when the car is off. You need a wiring diagram and a milliamp meter (your DVOM should have one) with clips on the ends of the leads. You never mentioned the year of your 240, whether wagon or sedan, accessories, etc. Things changed over the years. The accessories and circuits present on your car will determine the current demands when the key is removed. The newer and more sofisticated the electronics, the higher the current draw when parked. For most cars, after the dome light times out, there should be no more than the clock and radio memory pulling current; less than 50 mA, for sure.

To check key out current draw, remove the cable from the negative terminal of the battery. Remove all the fuses (and go ahead and clean the fuse holders; you'll never have a better opportunity). Install a milliamp meter set to the highest range in series with chassis ground and the negative post of the battery.

If that last sentence makes no sense to you, do not proceed. You need to understand the circuit and the procedure in order to do this. You can destroy your meter and maybe worse if you are not careful.

It is extremely important that you do not energize any circuit. Since you are working in the car, use a piece of duct tape to hold the door switch down. The dome light can pull enough current to damage the meter. Put the key in your pocket. Do not turn on anything. Note the meter reading with everything disconnected. It should be zero. If it is not, you have something pulling current right on the primary power circuit. It should be easy to find. That isn't likely though. ;-)

Now you can start putting fuses back one at a time. You should see no current until you install the clock and radio fuses (so do them last). But, you will. Something is pulling current when it should not. When you get to "the" fuse, stop. Use the wiring diagram to identifiy everything connected to that fuse and start opening circuits. You can start right at the fuse. Most of the fuses have more than one wire connected right at the fuse box. Lift them one at a time until the current draw goes away. Somewhere on that wire, something is pulling current.

Remember to remove the meter before turning anything on.

Let us know how it goes.
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Mr. Shannon DeWolfe -- I've taken to using mister because my name misleads folks on the WWW. I am a 52 year old fat man. ;-)