Power fluctuations on `83 240DL

Hello all,

I'm on the road and my 240DL has started giving me serious power problems. Turning on anything electronic reduces power from the rest of the system; the car just stopped being able to keep up with the power demands. For example, hitting the brakes causes the lights to dim. Turning the climate control fan on dims the lights- every step up brings quite a noticable drop in brightness. Also, high beams get stuck on, I have to turn the lights off, flash my high beams, and then turn my lights back on to disenguage high beams.

I've been running a 300 watt 120v inverter and a decent sized stereo for two weeks now off the system. They tap onto the positive terminal of the battery, and are grounded onto the chassis; I've disconnected them from the system but that made no difference in the cars performance. I still feel its notable, since they've undoubtedly been applying more stress to the alternator and voltage regulator.

The other thing I'm terrified about is that it could be a short. I've already replaced a bunch of wires with degraded insulation, but I wouldnt be suprised if there are more. Still, the problems dont seem symptomatic; I'm not blowing fuses.

I really havent the foggiest idea whats going wrong. I had my battery checked and NAPA told me it was ok. Still, these problems started not more than a day or two after I left my headlights on + needed a jump start. On the other hand, I have been stressing the power supply system in my car a little more than normal. If anyone has thoughts for what to check, what to try, whats going wrong, I'd really love the help.

Thanks

-Rektide

Reply to
rektide
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You had the battery checked, but did they check the charging system? Could be an alternator or regulator. Sears use to do that for free. Don't know if they still do. Also, check the battery cable connections at both ends of both cables. Loosen and tighten all four connections and clean the battery terminals and clamps. Run your hand along the length of both cables- check for stiff or swolen areas that would indicate that the cable needs replacing. Feel the fuse panel and local wiring for any that are abnormally warm. If it was a short then the related wire would be melted.

"rektide" wrote:

__ __ Randy & \ \/ /alerie's \__/olvos '90 245 Estate - '93 965 Estate "Shelby" & "Kate"

Reply to
Randy G.

The place to start is the alternator, pop out the regulator/brushpack and look at the brushes, if they're worn replace the assembly. Also check the ground wire from the alternator.

Reply to
James Sweet

Thats definately my main suspect. I'm thinking I'll probably try to just replace the whole unit with a GM SC-130, there's a couple people who've done that, they're good to 140 amps, some up to 200 A. That would be swell.

Rektide

Reply to
rektide

The problem was a weak ground. I replaced some groundings and it works just fine again. I also noticed more rotting insulation + replaced the cables.

I'm going to attempt a modification sometime soon and put in a GM SC-130 alternator. Some of them are good for 140 - 200 amps: just what the dr ordered.

Check your grounds!

Myren

Reply to
rektide

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