Author Topic: Problem with Delco 50DN and/or Delco Remy Voltage Regulator  (Read 5561 times)

Offline gumpy

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Re: Problem with Delco 50DN and/or Delco Remy Voltage Regulator
« Reply #15 on: July 01, 2014, 10:27:45 AM »
Well, there you go. I had forgotten that some have that extra terminal.

If your bus wiring has not been bastardized much, then the feed to the pos terminal should be coming through the master switch (which you
just said you verified), so jumpering the two as you did should be fine.
Craig Shepard
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Offline wagwar

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Re: Problem with Delco 50DN and/or Delco Remy Voltage Regulator
« Reply #16 on: July 01, 2014, 10:33:25 AM »
Beware the experts (BCM respondents not included). I fried the old VR by switching the adv VR from 'Positive Field control' to 'Negative Field control' upon recommendation from the Tech advisor at Sterling Power. He said the only possible damage would be a blown fuse! Needless to say he did not know what he was saying. The 50DN is definitely a 'positive field control' alt.

Now that I have it working again, the original problem was when the new Adv VR would kick in, the voltage out of the alternator would go up to 35 and then the adv. regulator would kick out. I found the same behavior with the adv. regulator even if I disconnected the Field wire coming from the old VR (so the old VR was removed from the system). So the adv. VR was not regulating the Field properly.

If the adv VR is not grounded properly how would I check that?

Offline bevans6

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Re: Problem with Delco 50DN and/or Delco Remy Voltage Regulator
« Reply #17 on: July 01, 2014, 01:36:31 PM »
I would check by measuring the resistance to a known good ground with a meter, or a continuity buzzer.  But - if it doesn't have a good ground it probably won't be putting out a full positive field voltage.  I would not try to run two voltage regulators in parallel, that just seems wrong to me.  I would probably substitute it for the now working standard regulator, wire for wire, and try it again.

Brian
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Offline gus

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Re: Problem with Delco 50DN and/or Delco Remy Voltage Regulator
« Reply #18 on: July 01, 2014, 08:31:08 PM »
If it is working your new VR is grounded, probably via the mounting bolts.

When your new VR was hooked directly to the old VR field terminal it was bypassing the old VR so it was completely out of the circuit, it was just acting as a terminal connector. I thought the new VR was connected to the Ign/Pos terminal which really confused me since this terminal needs full batt voltage.

Anytime the alt is producing 35+ volts too much voltage is getting to the field. Momentarily touching a 24v wire to the VR field connection is a quick way to check if the alt is working, but only momentarily!
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