Charging problem

I have a 1980 rabbit convertable. I just changed the alternator but is still only charging at 12 volts. Does this car have a regulator? It doesn't seem to have a ground wire either. Is that a problem.

Reply to
awronka
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measure voltage at the alt. with your Fluke. The regulator is integral to the alternator. A lot of times there's enough voltage drop that you can read 12V at the dash gauge and still be getting the correct 13.7 at the back of the alternator. Now what is a problem is if you aren't getting 13.7 at the battery - clean your cables if you have correct voltage at the alt. but not the batt. replace if necessary. also check all ground points for corrosion and clean as necessary. Finally I think

13.7 is too low, I'd like to see at least 14V but that is the Bosch spec. You can "hotrod" your alt. a little by getting a Transpo brand regulator with adjustable voltage setpoint, I thin kthey come set around 14.1V which is a nice compromise between high voltage to make everything work well and not overcharging the battery.

good luck,

nate

Reply to
Nate Nagel

Yes I believe the 80 Rabbit alternators are basically insulated from directly contacting the metal and getting a good ground. I still have some of those bushing kits too! lol There is usually some thick wiring to ground the alternators to the block or a metal bracket. And especially if the Rabbit has stock A/C.

I would add a ground to that alternator and check the voltage. If it still charges at a low level check the wiring plug to the alternator. Also there are some auto part stores that will check your alternator for free! ;-)

BTW Is this a Motorola or a Bosch alternator? Both should have an internal regulator so it should come with the alternator.

Reply to
dave AKA vwdoc1

So i should have a wire ground? Currently it only has the harness plugged in. The alternator is a brand new motorola. How do i check the voltage at the back of the alternator. Does the fact that I need to replace the fuse box have any bearing on this problem. The fuse box is currently rusted to pieces and am awating a replacement.

Reply to
awronka

does the alt/battery light on the dash come on with key on? Has to work or the alt will not put out.

Reply to
Lost In Space/Woodchuck

The alternator has a rather substantial ground strap that is bolted to the engine which attaches to the alternator which has a bolt on one of the studs on the alternator. It is also a good idea to ground it at a second point, There is a picture of the grounding stud on the alternator at:

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Reply to
jfruniontown

Another link re secondary grounding point --

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Reply to
jfruniontown

Ok I grounded the alternator, Changed the fuse box. However I now have a new problem. With the change of fuse box I got many of the essentials back, rear lights, brake lights, dome lights, windshield wipers working when they are supposed to. All nice.

But I now the car wont start. The fuel pump does not come on.However it does come on if I connect a wire near the box to one of the fuses. Apperently the pump had been jury rigged by some previous owner. This car has only 80,000 miles on it so I want it running well. Any tips to my new problem. Things i should look at. The car does have spark. It actually started acouple times after the fuse box change but has know stopped as it seems to be starved for fuel.. Any diagrams i could look at just incase i missed a wire here or there. The fuse box was definately the same model number.

Reply to
awronka

Was the wire bypassing the FP relay? They're known to fail.

good luck

nate

Reply to
Nate Nagel

Where is the Fuel pump relay? The fuel pump was not working when I restarted the car after changing the fuse box. Would running the engine out of fuel cause a problem and if so how do I fix it.

Reply to
awronka

----------------------------------------------------------------------------------------------------------- What color is the wire? I've got a couple schematics and I'll look for you. If the wire is a ( 16 gauge BK/g ) it is the power out of the fuel pump relay to the pump wire.

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Reply to
samstone

It's a white wire. There is also a green wire just hanging not connected to anything down there.

Reply to
awronka

I don't think i can help, sorry . The only white wire i found on the diagram on the fuse/relay box goes to the rear window defrost . :-( A green ( the only ones i can spot ) feeds power to the wipers.

Reply to
samstone

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