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What is the correct charging voltage?

 
Old 11-22-2014, 04:53 PM
  #16  
upstate bob
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as another 79 owner I have little trust in the panel volt gauge. Next summer I will take readings with an accurate one. I notice an extra wire coming off the hot post on the battery. Is that original like VWs have or did someone tap in for radio or speakers?
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Old 11-23-2014, 12:23 AM
  #17  
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if anyone is tackling the odometer repair now is also a good time to adjust the volt meter so it reads what is actually coming out of the alternator.

To do this remove the pod gauge pack , then the rear housing.
This will expose the alternator gauge,
find the rheostat,

place a towel onto the steering column,
plug the gauge pack into the connectors ,
rest the gauges on the towel,
start the engine ,
then take a reading at the hot post ,
then adjust your alternator so it reads the same as your reading,

put the pod gauges back together
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Old 11-24-2014, 06:16 PM
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Randy V
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It looks like the interior lights stayed on after closing the rear hatch, draining the battery.

My rear hatch lock switch just barely actuates when the hatch is closed. Is there any way to 'raise' the switch so it activates at a higher position?
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Old 11-27-2014, 11:03 AM
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Default Dead voltmeter

I had my 87 5-speed out last weekend for what was probably the end of the good weather here on long island. After making several stops, upon restarting the car, the dash lit up like a Christmas tree. Every possible warning light was lit, including the low oil pressure and the highe coolant temp lamps, belt tensioner, brake fluid, brake pad-you get the idea. The voltmeter gauge, which has always wagged like a dogs tail for YEARS was pegged at ten volts ( I have never seen it so low) I used to get 13.25-13.75 back at the battery post, now it's low 12's. The battery is about a year old and is kept on a Schumacher trickle charger all the time. Would a failing alternator-voltage regulator cause the dash to light up the way it did? Eventually it cleared up during driving and I got the car home, but it did reoccur again once upon pulling onto my town. What does the shark tank recommend? Grounds to chassis were done (cleaned) not too long ago
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Old 11-27-2014, 12:00 PM
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It is the alternator regulator for sure - that is the only thing that causes these symptoms.

The low voltage is because the alternator isn't generating, but the lights all come on due to the exciter line being driven low. Unless there is a short to ground on the exciter line - the only thing that can make it go to low voltage is the alternator regulator. An open circuit won't do it.

Now you have seen this - do the dash lights ever go out after starting?

Take the alternator in for testing - while the regulator isn't working - other faults in the alternator could be the cause of that so a full check over is in order. Remove the electrical connections first - don't dangle the alternator from the wires. Find a good local alternator/starter specialist shop if you can.

Alan.
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Old 11-27-2014, 02:06 PM
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Originally Posted by Randy V View Post
My rear hatch lock switch just barely actuates when the hatch is closed. Is there any way to 'raise' the switch so it activates at a higher position?
I'm not feelin' the love.

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Old 11-28-2014, 02:51 PM
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Originally Posted by Randy V View Post
It looks like the interior lights stayed on after closing the rear hatch, draining the battery.

My rear hatch lock switch just barely actuates when the hatch is closed. Is there any way to 'raise' the switch so it activates at a higher position?
OK - so I haven't done this - but I think you can change it. The switch is very open air and visible - but you have to remove the hatch receiver first to see it, it is an integrated part of that.

Make sure you have a good location defined for the reinstall of the receiver (masking tape frame around it maybe?).

You also need to pop the arm/cup off the hatch release motor cam, and disconnect the pin switch wire. Will need to remove the protection plate to be able to do this.

With the receiver out you can see how the pin switch works - terminal in the bottom connects via the white plunger pushing down against the spring - case is grounded

You need to screw/shim the bottom contact up or bend the contact up just a little for earlier contact. You may need to do some disassembly and fight with the spring a bit - but should be doable - biggest risk I see is the realignment of the hatch receiver on reinstall. You could see if there is any adjustment you can do with it in place - but this will be challenged for visual & manual access.

Found this pic that may help visualize.



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Old 12-01-2014, 01:49 PM
  #23  
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I'll give it a shot. Thanks, Alan.
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Old 12-02-2014, 07:45 PM
  #24  
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Default Correct charging voltage

Yes, thank you Allen. It is as I suspected, but I always ask the shark tank for confirmation. I will certainly be replacing the alternator with a quality rebuilt one, instead of just plugging in a new voltage regulator. Thanks again for your verification.
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