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MEXICOWANDERER's avatar
Oct 30, 2015

LandYacht Here's Your Voltage Regulator (RUSH!)

There's (3) available on eBay.

Old TRANSPO ELECTRONICS STOCK

NOT a standard Ford regulator



See the cover phillips head screws? There's a pot underneath.

On the reverse side there is a FIFTY AMP TO-3 power transistor on a heat sink.

Inside are a couple of MR2535 avalanche rectifiers.

http://www.ebay.com/itm/Transpo-F540HD-Voltage-Regulator-FORD-1G-40-65-Amps-Heavy-Duty-/151837580701?hash=item235a399d9d:g:OeQAAOSw3xJVa1M2&vxp=mtr

This is a piece of cake to use with your alternator.

If I were you I would buy one to eat now and one to save for later. This unit has been out of production AND THE EBAY PRICE IS THE SAME AS WHAT I WAS PAYING FOR THEM THIRTY YEARS AGO.

60 Replies

  • I've got a dremel with a drill type chock which can clamp down on super tiny drill bits which should get through the potting, but still, if the POT thing is flat to the PCB, I see problems.

    Mad scientist time. How about two regulators, one set to 14.4v, one set to 13.6v and flip a switch to choose either voltage?

    Not much luck finding a red VR connector, all I see is the SMP s94



    http://www.rockauto.com/catalog/moreinfo.php?pk=50395&cc=1126156&jnid=1198&jpid=1

    Looks like junk.

    I think I'd rather crimp and solder and adhesive line heatshrink my Own female quick connects and figure out some strain relief so they cannot pull off without extreme effort.
  • Yup dat's the little p--- pot grinnin atcha...

    Soft plastic potting. I use a PC board finger powered drill and dental probes to root around.

    Seeing WHERE Mopar mounted the computer and how jittery the voltage is, I wouldn't put it past them to have made the CPU field wire input ultra sensitive. Those boys had pure lard atwix the ears when they got to the CPU voltage regulator fault code design. "Hey Bubba! Gotta idea! Let's made the engine run rough as hell, lose overdrive, and suck gas like an ought-six round went through the gas tank, to lettum know the alternator ain't workin'"

    Each brush has it's own terminal. You can reverse the connections and the alternator could care less.

    Voltage value variances for the S terminal can be compared to screaming FIRE in the key of G in a crowded theater rather than than the more robust key of A. The reg will work. But you won't get trampled thank goodness. Voltage at the A terminal however is critical. Zatz why the gobbed on silicone grease recommendation.
  • Thanks for the info and recommendation to use this superior product which you also found and linked.

    . How tightly pack are the internals around the internal POT? Is the potting soft silicone or a hard epoxy? Is it one of those Blue pots like shown here?



    Say I successfully get a 1K ohm pot externally wired in. What happens if I lower it too quickly, past a 13.6v setpoint faster than battery voltage would naturally decline? Can I release magic smoke by getting twiddle happy with the pot?

    When I lower voltage too quickly on my Meanwell something clicks and output goes to zero until battery voltage falls enough, then it clicks back on. The cheapowatt it made an ugly high pitched sound when voltage was lowered faster than the battery could bleed off the extra voltage.

    I take it My light blue Z1 wire should not be the source of the switched ignition feed as it might screw with the 'trick the ECM' resistor which is to be inline between the current field terminal wires.

    I can pull a wire from the ignition switch, one that powers the window motors and blower motor and is disengaged during engine starting. Should this be on a relay?

    As my 50/120 rests now, unmodified, does one field terminal stud go to one brush and the other FT to the other brush?
  • Ignorance demands placing the ECU and connectors adjacent to a lead acid battery. Total ignorance means not spending the few cents it would take to gold flash the ECU connectors, similar to connectors with computer. Dimwit bean counters rule Detroit. They are given free cars every year. They are as disconnected from reality as the dimwits on Capitol Hill.
  • My 50/120 alternator has two field wire connections. To one of these comes a wire from the Transpo VR's "F" terminal. The other alternator field terminal stud gets a new wire run to the alternator casing ground? PERFECT

    My existing field wires, one is Z1 system voltage on a light blue 14awg wire, the other field wire is green 14awg, it goes into the ECM. The 'trick the ECM resistor' is to be wired between these two existing wires after removal from alternator to keep the CEL/MIL light off. I WOULD MUCH PREFER TO NOT FOOL WITH THAT CONNECTION. FIND ANOTHER IGNITION SOURCE BUY NOT IGNITION COIL POSITIVE. VOLTAGE LEVEL TO THIS THE "I" TERMINAL IS NOT CRITICAL.

    "chop the alternator brush field terminal with dikes" WTF does this mean? Am I to be modifying the 50/120 alternator internally to get this regulator to work? I'd like to be able to disconnect the 'trick the ECM' resistor and return VR duty to the ECM if needed without removing alternator from vehicle. BELAY MY SUGGESTION BECAUSE OF YOUR STATEMENT THAT THE RESISTOR GOES IN THOSE TWO WIRES. REFER TO MY ANSWER ABOVE. FOLLOW THE AFTERMARKET GIZMO INSTRUCTIONS EXACTLY,

    Now you know my desire to reach the VR's potentiometer from the driver's seat. I am assuming I can either drill a hole in the casing over the pot and have a non electrically conductive means to twist the pot, or perhaps I can desolder the pot and run wires in its place to a larger remotely mounted Pot. No doubt the VR is potted, what are the chances of desoldering. I did this successfully on the cheapowatt and Meanwell. But they were not potted. THIS IS GOING TO REQUIRE PATIENCE. THE POT IS FLUSH WITH THE POTTING. BY TINY DRILLING AROUND THE PERIPHERY OF THE POT, IT CAN BE MADE LOOSE FROM THE POTTING. YOU NEED TO DISSECT THE POT WITH FLUSH CUTTING PLIERS FROM THE OUTSIDE EDGE, INWARDS. PRACTICE TILL PERFECT ON A SIMILAR SACRIFICIAL POT OR TWO TO GET THE PROTOCOL DONE IN RELIABLE FASHION. A 1k VALUE POT IS PLENTY. UNLIKE THE MEGWATT ET AL THE HIGHER THE RESISTANCE THE HIGHER THE VOLTAGE. PRESET THE REPLACEMENT TO 200 OHMS ON STARTUP. USE JB QUICKWELD TO RE-POT ONLY AFTER A COMPLETE PROOFING OF MODIFICATION RELIABILITY AFTER INSTALLATION.

    I'm not afraid to mount the VR where accessible for pot twiddling from driver's seat, but I'd rather have a remote Pot right next to my digital voltmeter on the dash, and the VR casing will not mount right here easily/cleanly, without looking like a big wart. I'd like to have it hidden behind dashboard. Any benefit to additional heatsinking? IF MEMORY SERVES THE VALUE OF THE VOLTAGE DIVIDER NETWORK WAS <.03 AMP

    Kind of feeling like I am opening a can of worms just to get my voltage regulation in line with 'Ideal' desires, but I am learning. I've always hated knowing that if the VR inside the ECM goes belly up I'd have to do something like this anyway, but I was planning on using the standard Mopar external regulator, not trying to make a heavier duty Ford regulator work in its place. THE TRANSPO AND EVERY OTHER EXTERNAL MOPAR REGULATOR HAD THEIR OWN SIGNIFICANT WEAK LINKS. YOU WOULD NEED TO WIRE IN A RELIABLE RELAY THEN START DIGGING INTO THE 8313 POTTING. I REPLACED UNCOUNTED MOPAR REGS WITH THE F540 SERIES ELIMINATING THE NEED OF A RELAY. MOPAR PLUGS WITH SPRING STEEL RETAINER ARE NOT AVAILABLE. I HAD GIVEN THIS A LITTLE THOUGHT BEFORE RECOMMENDING A REG TO YOU.

    THE STANDARD MOPAR REG SET POINT IS 14.4 VOLTS.
  • Okay I've read and reread your edited post a few times now.

    Don't let your optic nerve get stretched too much with the eye rolling of the following questions. Remember I do not have a background in this stuff.

    My 50/120 alternator has two field wire connections. To one of these comes a wire from the Transpo VR's "F" terminal. The other alternator field terminal stud gets a new wire run to the alternator casing ground?

    My existing field wires, one is Z1 system voltage on a light blue 14awg wire, the other field wire is green 14awg, it goes into the ECM. The 'trick the ECM resistor' is to be wired between these two existing wires after removal from alternator to keep the CEL/MIL light off.

    So I run another 14awg light blue wire from Z1 hub to the "S" terminal on the VR as my switched ignition. Any fuse needed?

    The Transpo VR case gets well grounded directly to Alternator casing. Mine does have a (-) stud.

    "chop the alternator brush field terminal with dikes" WTF does this mean? Am I to be modifying the 50/120 alternator internally to get this regulator to work? I'd like to be able to disconnect the 'trick the ECM' resistor and return VR duty to the ECM if needed without removing alternator from vehicle.

    Ignore the idiot light terminal, done.

    A: battery reference always hot. I do have upgraded cable, but it might be just as easy to run a wire right to battery(+), or at least my 'common' feed on my Blueseas 1/2/both/off switch. Am Assuming this wire carries little current, can be thin?



    Now you know my desire to reach the VR's potentiometer from the driver's seat. I am assuming I can either drill a hole in the casing over the pot and have a non electrically conductive means to twist the pot, or perhaps I can desolder the pot and run wires in its place to a larger remotely mounted Pot. No doubt the VR is potted, what are the chances of desoldering. I did this successfully on the cheapowatt and Meanwell. But they were not potted.

    I'm not afraid to mount the VR where accessible for pot twiddling from driver's seat, but I'd rather have a remote Pot right next to my digital voltmeter on the dash, and the VR casing will not mount right here easily/cleanly, without looking like a big wart. I'd like to have it hidden behind dashboard. Any benefit to additional heatsinking?

    Kind of feeling like I am opening a can of worms just to get my voltage regulation in line with 'Ideal' desires, but I am learning. I've always hated knowing that if the VR inside the ECM goes belly up I'd have to do something like this anyway, but I was planning on using the standard Mopar external regulator, not trying to make a heavier duty Ford regulator work in its place.
  • The regulator case MUST BE GROUNDED on all external Ford regulators. This F540is the product of a liaison between myself and Frank Oropeza of Transpo in Agostino's restaurant in Ft Bragg in 1982. I ranted and carried on about the propensity of B circuit regulators to latch (destruction) when battery reference negative was removed from the circuit. Absolutely positively zero voltage droop from .1 amp field to 20 amps of field current. This reg is .01 stable. And it does not Laurel& Hardy if ground reference is lost.

    F) field to one alternator brush. The other brush must be negatively grounded to the case.

    S) signal from ignition switch. One of your existing field wires to a brush on the alt is a super quality ignition signal source. Extend it to the regulator S terminal

    I) used when an indicator light is needed - an idiot light. Leave unconnected.

    A) means a+ battery reference always hot. It doubles as the regulator reference voltage input and source power for the field F terminal circuit. I like the overkill this circuit with a 12-gauge power wire. Now, if you have a superb alternator to battery positive post circuit (which would mean you upgraded it) you can cheat and connect the regulator A terminal to the alternator output stud. Makes the circuit handy, and shorter - no cross compartment runs.

    Chop the alternator brush field terminal with dikes. I like to use 14-gauge wire here because of mechanical strength. Solder all terminals and splices. Run to a shiny clean ground.

    Run a 14-gauge wire from the regulator F terminal to the OTHER brush terminal on the alternator. Solder.

    I SOLDER A 1/4" 12 gauge ring terminal to the regulator case. Remove the irridite plating first. Gob on the solder. Use a plated bolt or wood dowel to keep the holes aligned. 12 gauge wire to the engine in harness with the F and I wires to the alternator. I like external tooth lock washers for all this.

    Go online. Go to eBay.

    SEARCH Ford External Voltage Regulator Plugs.

    There are two types of plugs. Both fit. One is junk.

    The plug you want is RED. It has a plastic bridge retaining loop that keeps the plug snapped onto the regulator. The junk one waits until heavy night time traffic, with cloudburst, then slips off the regulator terminals.

    The regulator and plug terminals are all cad plated. Smother them with electrolytic silicone grease, including the side where the wires enter the red regulator plug. Smother the riveted terminals beneath the reg. The soldered regulator ground wire is bullet-proof.

    Hope this helps. Transpo set the reg for 14.0 volts. Have a ball with the pot.

    BUT keep in mind the lid is metal and the stuff inside angers easily.
  • Ordered one.

    I am assuming since it has 4 contacts that the VR's case need not be grounded?
    That one of the contacts is ground, one a relayed ignition on Hot, and the other two for the field?

    What made you decide to find this New Old Stock gem?

    Now I guess I got to order that trick the ECM resistor too.
  • There are NO mistakes with url cut and paste. Someone somewhere is huffing and puffing on wacky weed.

    Thanks Don


  • MEXICOWANDERER wrote:
    There's (3) available on eBay.

    Old TRANSPO ELECTRONICS STOCK

    NOT a standard Ford regulator

    See the cover phillips head screws? There's a pot underneath.

    On the reverse side there is a FIFTY AMP TO-3 power transistor on a heat sink.

    Inside are a couple of MR2535 avalanche rectifiers.

    http://www.ebay.com/itm/Transpo-F540HD-Voltage-Regulator-FORD-1G-40-65-Amps-Heavy-Duty-/151837580701?hash=item235a399d9d:g:OeQAAOSw3xJVa1M2&vxp=mtr

    This is a piece of cake to use with your alternator.

    If I were you I would buy one to eat now and one to save for later. This unit has been out of production AND THE EBAY PRICE IS THE SAME AS WHAT I WAS PAYING FOR THEM THIRTY YEARS AGO.

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