Charging circuit in 1982 TDT only putting out 13 +/- .2 volts

The charging circuit on my 1982 300 TDT is only putting out about 13 volts. If I put a voltmeter on the battery I get about 13 volts measured. Then if I start the engine and rev it up, I can see a
slight increase, like maybe .2 volts, but not what it should. On my two Toyotas the alternator ups the voltage up over 14 volts.
I have a replacement Bosch alternator I bought from a Mercedes dealer. (I had a back injury and the alternator went out when I was on the road on a business trip, so I had to have the dealer replace it. $$$$)
I took the voltage regulator/brush assembly out today. It shows a little wear, but the brushes are still pretty long and it looks fine. The red idiot light for the alternator comes on when I turn the ignition on, and goes out when the engine starts and stays dark when I drive along, but the system is not putting out enough to keep the battery charged, especially if I run the sound system and use cruise control and have the automatic climate control engaged.
Does anyone have any ideas of what tests I should run? Or any other suggestions?
Thanks.
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How old is the battery?
Have you had the battery tested?
The battery condition dictates the amount of charging voltage and current.

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The battery is about 6 months old. It's a DieHard International, but has been deep cycled a few times. It takes a charge from my trickle charger, and did charge up last week when I drove the car with no accessories on. That was after I had driven 40 highway miles, parked at a supermarket, and found that the battery would not turn the engine over when I came out from shopping. I got a jump start from someone and then drove 20 miles with the accessories off and the battery was charged enough to start the car. But yesterday I put a trickle charger on and the battery seemed to have become discharged somewhat again because it took 4 amps for a few hours before the 6 amp charger's meter indicated it was only putting out 2 amps. I'll check the voltage again this morning and see if the alternator can do better with a fuller charge on the battery.
I can take the battery into Sears this week and get it tested.

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I should add that I drove home 40 miles with the full accessories, cruise, headlights, etc. after I started the car again on that trip.
The car started fine all week, so maybe it's OK, but I don't want to get stranded again.
Paul

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Have you installed any items that might drain the battery lately. I ask because I installed a cell phone amplifier that remained on after the car was shut off (e430) and it exhibited similar behaviour.
I would run the following test:
Remove negative battery cable from the battery.
Using a 12-volt test light, hook one end to the negative battery post the other end to the negative battery cable you just disconnected. The test light will glow or "light" if there is a drain.
If the "light or glow" is faint, that is probably normal draw for the clock or computer.
If the "light or glow" is bright, then there is a large drain.
That should be corrected. Now start removing and replacing the fuses one by one until the light goes out; that one will be the circuit with the drain.
Remember to hold in the button in the door jam for the interior lights.
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I would run the following test:
Remove negative battery cable from the battery.
Using a 12-volt test light, hook one end to the negative battery post the other end to the negative battery cable you just disconnected. The test light will glow or "light" if there is a drain.
If the "light or glow" is faint, that is probably normal draw for the clock or computer.
If the "light or glow" is bright, then there is a large drain.
That should be corrected. Now start removing and replacing the fuses one by one until the light goes out; that one will be the circuit with the drain.
Remember to hold in the button in the door jam for the interior lights.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A more accurate test is to use a multimeter set to DC milleamps. Ant draw more than 30 milleamps will drain a battery.
And if you open a door, you need to reconnect the battery so the dome light turns off, IF you have the large front dome light. Just holding the button in after you open the door still leaves a massive draw because the timer circuit in the light assembly was triggered. It does not get enough current thru the test light or multimeter to cycle off.
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Thanks. I just took the battery out of the car and it may be the battery. I had the AC worked on this summer, and the nitwit punk "mechanic" at the AC place really screwed up a lot of things, including making a hose that blew the second day after I got the car back. He also didn't remove and replace the ground wire's battery clamp by loosening it. He must have pried it off and pounded it back on, because he cracked the case of the battery and probably broke some of the internal connections. I will know better after I get the battery tested at Sears. The thing that burns me up is that he will have voided the warranty unless the kid at Sears is equally incompetent and does not notice the small crack in the case. I had just gone to war with the AC place to get a refund on the work that failed, and it was only after that that I noticed the battery cable was not on properly and that the case had been cracked by a ham fisted idiot, so I just epoxyed the crack hoping the battery would be OK because I was sick of arguing with the owner at Auto Air and More at Las Vegas on Tropicana.
I am still finding things that that dope fouled up. Yesterday I replaced the homemade hose that ruptured that he put on with an actual replacement part and to do it I had to remove the cruise control actuator and discovered that he apparently lost one of the bolts that hold the bracket down and had cross threaded in a bolt that wasn't right in its place, semi stripping one of the holes in the mount bracket. Also, he had put my air cleaner housing on with the oil drain from the housing outside the drain tube leading to the oil pan, thereby exposing my oil to drawing in air through that tube straight in to the crankcase unfiltered. Also he broke one of the rubber air cleaner housing mounts. Just great drawing air unfiltered into the crankcase on a new motor I just spent 6 grand on! That kid is lucky I can't get my hands on him this morning!
That's why I never let anyone touch my vehicles, but they don't let you fill your own AC anymore, which, in my case, is stupid. I would not have put together a system that blew in two days . . .
I have to try and cool down before I go in and try and get the owner to make good on that battery next week or I may get myself in trouble . . .
Thanks for the 30 miiliamp figure.

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Don't get into trouble!
Go to the Better Business Bureau, in an area like Vegas. They'll love to put a seedy shop on notice, that they are on the shit list. They can negotiate to a certain extent.
Then, there's Small Claims Court.
You seem like you are good with your hands, and have a better chance of winning, than an all thumbed Academic.
o this is your rectum before jail, O this is your rectum after jail!
I wish you well.
RK

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Thanks. I just took the battery out of the car and it may be the battery. I had the AC worked on this summer, and the nitwit punk "mechanic" at the AC place really screwed up a lot of things, including making a hose that blew the second day after I got the car back. He also didn't remove and replace the ground wire's battery clamp by loosening it. He must have pried it off and pounded it back on, because he cracked the case of the battery and probably broke some of the internal connections. I will know better after I get the battery tested at Sears. The thing that burns me up is that he will have voided the warranty unless the kid at Sears is equally incompetent and does not notice the small crack in the case. I had just gone to war with the AC place to get a refund on the work that failed, and it was only after that that I noticed the battery cable was not on properly and that the case had been cracked by a ham fisted idiot, so I just epoxyed the crack hoping the battery would be OK because I was sick of arguing with the owner at Auto Air and More at Las Vegas on Tropicana.
I am still finding things that that dope fouled up. Yesterday I replaced the homemade hose that ruptured that he put on with an actual replacement part and to do it I had to remove the cruise control actuator and discovered that he apparently lost one of the bolts that hold the bracket down and had cross threaded in a bolt that wasn't right in its place, semi stripping one of the holes in the mount bracket. Also, he had put my air cleaner housing on with the oil drain from the housing outside the drain tube leading to the oil pan, thereby exposing my oil to drawing in air through that tube straight in to the crankcase unfiltered. Also he broke one of the rubber air cleaner housing mounts. Just great drawing air unfiltered into the crankcase on a new motor I just spent 6 grand on! That kid is lucky I can't get my hands on him this morning!
That's why I never let anyone touch my vehicles, but they don't let you fill your own AC anymore, which, in my case, is stupid. I would not have put together a system that blew in two days . . .
I have to try and cool down before I go in and try and get the owner to make good on that battery next week or I may get myself in trouble . . .
Thanks for the 30 miiliamp figure.

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Reminds me of a similar experience I had with a Pontiac 6000STE that I took to a local AC shop for a problem with the AC. It took them forever to diagnose that the problem was the control switch in the dash. When I picked the car up, now the check engine light was on, but I didn't notice it until I had driven off and I had picked it up just as they were closing, so I couldn't go back.
This was back in the days when to read out the fault code, all you had to do was short two pins together under the dash. I did, and the fault code was: Engine Coolant Sensor.
So, I figured this must just be a coincindence, or they knocked a wire off. And off course, like heav, I also questioned the competence of this AC shop, because it took forever to figure out the AC problem, which was just the switch. So, I decided to investigate further on my own. I traced the problem all the way back to the car computer. Finally, I took that out, and upon investigation there was a small spot on the circuit board that was clearly blown out. I repaired it with solder and Voila!, problem fixed.
I'm 100% certain that in the course of their screwing around, they wound up connecting 12V back into the computer somehow, which blew out the circuit board trace.
I guess I could have taken it back and demanded they fix it, but not sure where that would have lead. It's very possible they would have just made things worse or denied that the coolant temp issue was their fault.
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Did the newly installed alternator include a new regulator? The voltage regulator is housed in the alternator. It could be that the old regulator was transfered from the old to the new alternator. Look at the bill to see what was included - or not.
Also, I agree with Karl about the battery - highly suspect if > 4 years old.
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