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electrical issue!!! who's surprised?

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jmayzer

jmayzer

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i'm running out of ideas for my 65 midget.


the car is having a problem keeping a charge. i had my generator professionally rebuilt, a new fuse box, a new battery, and a new voltage regulator, all within less than a year. regardless of all these steps being taken, i still have to jump the car every time i want to start it, the headlights are not at full brightness and the horn does not work properly unless i'm giving the car gas. i started it up last night and after it was running for a good 10 minutes or so, i tested the battery with a voltmeter and i got a solid 12.2-12.5 volts. however, even if i drive the car around for a solid 20-30 minutes, as soon as i shut it off, it's dead and won't start back up even 10 seconds later.


......help:blue:
 
This sounds to me as if the system is not grounding properly. Check voltage from the positive post to the engine and see what voltage you get. Also, check how for the battery voltage drops when the starter is engaged. let us know what the results are. Dave
 
You mentioned that the voltage regulator is new. Did you clean the contacts inside the regulator before placing it in service? They typically ship with a protective coating on the contacts which prevents them from corrosion when in storage. The coating also prevents the regulator from working properly if it is not removed.
 
I would check the voltage regulator. Even though they say they are preset that isn't always the case. I had a problem with a battery going dead and we kept replacing the generator. Finally a young kid who worked part time for the mechanic I was using at the time said maybe it is the voltage regular and the mechanic said "no it is preset". Well the kid checked the voltage regular and it was set wrong and he reset it and WALA no more problems. This was after trying three or four different generators. You should have seen the look on the mechanic's face.
 
good news gents! apparently my old voltage regulator totally discharged my battery, so when i plugged my new one in, the battery was still giving me trouble. i charged up the battery for a solid 24 hours and now she fires right up. this is all a learning process, right?
smilie8.gif


at idle, my voltmeter is reading a about a 12.38-12.41 - sound about right? my headlights still are only at their full brightness when i idle higher though.....

cheers,

jake
 
Readings close to 12.5V only indicate a fully charged battery and don't say anything about whether or not the control box is working. You will have a better idea what's going on if you drive around with a voltmeter connected to the car and observe the system voltage when the engine is turning at least 2000 RPM. For charging you want a 1V to 1.5V increase in the at-rest battery voltage (i.e. At 2000 RPM you want to see a system voltage of perhaps 13.5V to 14V).

EDIT: I forgot to mention that with the freshly charged battery the engine will be able to start quite a few times and run for many miles. Don't let that lull you into a sense of security. Measure the charging system voltage at 2000 RPM and confirm the system is charging so you don't get stranded somewhere by a discharged battery.
 
Sounds like things are coming along well, Jake. You'll have to bring your beast down here one day. We've got some great back roads around here.
 
Is there a ground strap from engine to body? Check that it is contacting well and no paint at the bond.
 
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