New Swap, Not Charging

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shittyslant6

shittyslant6

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So I just swapped out my slant 6 in my 1970 Duster for a 1973 318.
The engine runs fine, there is no problems in the electrical system other than the alternator does not charge and sometimes the key does not do anything but click. (that is an isolated problem because it did that before the swap and it charged fine then)

I have already switched out the alternator that came with the v8 for the one that came off of the slant. (known good, the v8 I did not know) Still not charging. Then I replaced the wire ends as they were ruined. (new connecters and heat shrink.) I thought that maybe the green and blue wires were backwards on the alternator, so I switched them and that did not fix the problem either.
Still not charging.
Is there anything I am missing?
 
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May not be the cause, but did you install the ground wire from the engine block to the firewall when you did the swap. Bad grounds can cause a lot of strange issues.
 
Mike69cuda said:
May not be the cause, but did you install the ground wire from the engine block to the firewall when you did the swap. Bad grounds can cause a lot of strange issues.
Click to expand...
yes, I did not have one initially, but I have one now.
It goes from the back of the head to the heater motor thing on the passenger side.
 
With all wiring connected, turn key to "run" and 'back probe' the alternator field connectors. If you cannot reach both with the meter probes, reverse them. the blue should have 12V with key on. The green should be quite lower. You can also remove / replace the green while watching in subdued light and listen. There should be a small spark every time.

"Wiggle" the VR connector pull it in/ out several times to scrub the connections and "feel" for tight. Visibly inspect the terminals for corrosion.

Take a jumper and remove the green field wire at the alternator, and connect that exposed field terminal to ground. Again watch for spark when connected / disconnected. Start car, run up RPM "gently" and watch ammeter/ voltmeter. Voltage should come up, ammeter should swing to "charge."

If not, put a voltmeter on alternator output stud. Compare that reading to battery, and run engine, and watch for increase. If voltage goes sky high, 20V or more, you have a break in the path from alternator to batttery.

If this happens, make CERTAIN VR is grounded, and if so, try another VR
 
HOW THESE work after '70

The VR has two (three) terminals, ground (the case), green, the field, and blue, the igniiton/ power which is also "sensing."

The green field wire controls the "grounding" of the field. The other end of the field gets 12V through the blue wire. The VR controls the current through the field, and more current causes more output from the alternator.

To test the alternator you need several conditions:

1...Make sure the V belt is not slipping
2...Set it up to get 12V field current so connect 12v to one field terminal and ground the other. Does not matter which is which

It MUST draw field current. Bad brushes, grease/ dirt making brushes stick in holders, etc
3....If it will not charge, there might be a break in the output circuit----wire end terminal, black through bulkhead, welded splice in the harness, through the ammeter, back out bulkhead, through fuse link, to starter relay stud, and to battery. Any failure in that path will isolate the alternator output

If you do not have one, wander over to MyMopar and download a free service manual.
 
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67Dart273 said:
With all wiring connected, turn key to "run" and 'back probe' the alternator field connectors. If you cannot reach both with the meter probes, reverse them. the blue should have 12V with key on. The green should be quite lower. You can also remove / replace the green while watching in subdued light and listen. There should be a small spark every time.

"Wiggle" the VR connector pull it in/ out several times to scrub the connections and "feel" for tight. Visibly inspect the terminals for corrosion.

Take a jumper and remove the green field wire at the alternator, and connect that exposed field terminal to ground. Again watch for spark when connected / disconnected. Start car, run up RPM "gently" and watch ammeter/ voltmeter. Voltage should come up, ammeter should swing to "charge."

If not, put a voltmeter on alternator output stud. Compare that reading to battery, and run engine, and watch for increase. If voltage goes sky high, 20V or more, you have a break in the path from alternator to batttery.

If this happens, make CERTAIN VR is grounded, and if so, try another VR
Click to expand...
Take a jumper and remove the green field wire at the alternator, and connect that exposed field terminal to ground.
Click to expand...
Do you mean battery ground, or just ground the wire to something metal?
 
Just a thought...
Op stated that he did mot have ground strap attached originally and that the key will sometimes only click.

Is it possable that some connections ( bulkhead etc) got toasted before the ground got attached and are now making bad connections?
 
shittyslant6 said:
Do you mean battery ground, or just ground the wire to something metal?
Click to expand...
Well make sure it is a GOOD ground. Engine block is good. "Something metal" may or may not especially in a swapped car where "you might not have noticed" a missing grounding wire.............In other words if it's a front mount battery, the main large cable should ALWAYS go to the block (heavy starting current) but the jumper from battery to body or from block to body were always "questionable" because "back then" there were minimal loads. In a swap situation, you may have forgotten a ground jumper, or have additional loads that requires much better battery/ engine ---to body grounding.

"What I like" is EG on a B/RB or SB look at the front of the pass side head. Those bolt holes also appear on the rear of the driver side head Install a short bolt, and use a "starter cable" (eyelet to eyelet) about a foot ---1 1/2 foot long--one end to bolt in head, other end to solid ground on the body--such as the master cylinder studs, or even a "through" bolt with star lock washers
 
Once long ago, I had the 440 out of my then 70 RR, and it had a trunk mount battery, grounded to trunk/ body. I had forgotten to bolt up the front jumper from the sub-frame to the block. Went to start it, and BLEW UP one of the spring clips on the clutch linkage!!!!
 
67Dart273 said:
With all wiring connected, turn key to "run" and 'back probe' the alternator field connectors. If you cannot reach both with the meter probes, reverse them. the blue should have 12V with key on. The green should be quite lower. You can also remove / replace the green while watching in subdued light and listen. There should be a small spark every time.

"Wiggle" the VR connector pull it in/ out several times to scrub the connections and "feel" for tight. Visibly inspect the terminals for corrosion.

Take a jumper and remove the green field wire at the alternator, and connect that exposed field terminal to ground. Again watch for spark when connected / disconnected. Start car, run up RPM "gently" and watch ammeter/ voltmeter. Voltage should come up, ammeter should swing to "charge."

If not, put a voltmeter on alternator output stud. Compare that reading to battery, and run engine, and watch for increase. If voltage goes sky high, 20V or more, you have a break in the path from alternator to batttery.

If this happens, make CERTAIN VR is grounded, and if so, try another VR
Click to expand...
Ok, with the key in the run position, the blue wire on the alternator is getting 10.9 volts. and the green is getting 0.8volts.
 
shittyslant6 said:
Ok, with the key in the run position, the blue wire on the alternator is getting 10.9 volts. and the green is getting 0.8volts.
Click to expand...
key in run, with the exciter wire hooked on a block ground, and replacing the green wire, I get 11.5 volts to the blue wire.
 
67Dart273 said:
Well make sure it is a GOOD ground. Engine block is good. "Something metal" may or may not especially in a swapped car where "you might not have noticed" a missing grounding wire.............In other words if it's a front mount battery, the main large cable should ALWAYS go to the block (heavy starting current) but the jumper from battery to body or from block to body were always "questionable" because "back then" there were minimal loads. In a swap situation, you may have forgotten a ground jumper, or have additional loads that requires much better battery/ engine ---to body grounding.

"What I like" is EG on a B/RB or SB look at the front of the pass side head. Those bolt holes also appear on the rear of the driver side head Install a short bolt, and use a "starter cable" (eyelet to eyelet) about a foot ---1 1/2 foot long--one end to bolt in head, other end to solid ground on the body--such as the master cylinder studs, or even a "through" bolt with star lock washers
Click to expand...
i just rechecked all grounds, and they are good. main ground is connected to the front of the head on the block, and the body ground is in the factory location on the core support.
Then there is a ground strap I put on the back of the head on the passenger side going to the firewall.
 
shittyslant6 said:
i just rechecked all grounds, and they are good. main ground is connected to the front of the head on the block, and the body ground is in the factory location on the core support.
Then there is a ground strap I put on the back of the head on the passenger side going to the firewall.
Click to expand...
Keep going I have the exact same issue but my green had way more voltage in run and I think that is a bad VR?
 
67Dart273 said:
Once long ago, I had the 440 out of my then 70 RR, and it had a trunk mount battery, grounded to trunk/ body. I had forgotten to bolt up the front jumper from the sub-frame to the block. Went to start it, and BLEW UP one of the spring clips on the clutch linkage!!!!
Click to expand...
It just couldn't handle the amps. They should have designed it better. lol
 
4.7Light said:
Keep going I have the exact same issue but my green had way more voltage in run and I think that is a bad VR?
Click to expand...
Well I did not figure out for sure, but I pulled it off the VR today to clean it up and see if it was grounded correctly.
Well wouldn't you know it the back of it was bulging out and it was really cracked. not sure how it wasn't leaking. the new one will be here in 4 days.
 
See had you left the slant 6 in, none of this would be happenin. Traitor. lol
 
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