View Full Version : Feild plates ext reg.

D-MAX 2112
08-03-2012, 01:07 PM
Hello all
I'm wiring a ext reg to field plates on leece 320's
The ground post on the field plate goes to the body ground? Or back to the ground connection on the regulator?

08-03-2012, 09:56 PM
im not sure i understand the question but if this helps on mine theres two pins one gets fed positive from the external reg the other gets grounded to the ground post of the alternator which will also be grounded either to your frame body batterys or wherever you have it attached basically it energizes the rotor to begin generation

D-MAX 2112
08-04-2012, 04:40 AM
Thanks Doughboy.. exactly what i was looking for ..thanks. Arent the Alts grounded being attached to the bracket which is bolted to the head? Just thinking aloud here

Keith 2112

08-04-2012, 06:10 AM
The ground stud on the back of the leece is mounted in plastic if you test continuity between that stud and alternator case you will see it is isolated so grounding the case like on a typical gm alt doesnt work

D-MAX 2112
08-04-2012, 07:20 AM
I was just checking with the meter..i see its isolated!.. i didnt realize that.. Good thing i asked some questions and you gave the good answer!. I will need to run a wire from the ground studs to myalt bracket for each alt..which i chked via fluke is a good ground. Dam i would have made a mistake!

Thank you thank you

D-MAX 2112
08-04-2012, 07:21 AM
My noob-ness is showing!

08-04-2012, 07:33 AM
Make sure the ground wire is as big as your power wire because it is a complete circut and thin ground will choke it

08-04-2012, 07:35 AM
Also if possible ground them all to a commin point helps avoid ground loops

D-MAX 2112
08-04-2012, 02:28 PM
Thanks Doughboy..

Im working with 3- 2/0's and the grounds will be short from the Alt ground stud to the alt bracket..which with the fluke tests a good ground...they all will be going to a common point. I do want to put 1 large 2/0 ground from the engine block to the frame .This big diameter wire can be a pain.. good thing its that welding wire and very flexible.
I looked under the field plate..looks like the long studs have the brush spring around the screw.. Man im in an area ive never been im hoping i dont have a mistake somewhere and burn up an Altrernator..these leeces arent cheap as you know.

08-04-2012, 03:08 PM
One iportant thing some external regs will burn up if you ground the cabinet of the reg most newer ones dont have this issue just be sure to check everything for shorts if your field plates are fb ones that are aluminum dont tighten the bolts to much their insulated from the plate with oring which could tear and short out make sure all wires from back of alts feeding batteriers are attached before turning them on if theres no load on the alts when they charge they can cook when all done check field bolts to plate with meter for shorts the alternators are pretty tough but if you short the big welding wire it could be an issue just take your time youll get it

D-MAX 2112
08-05-2012, 06:55 PM
Now im confused i ran a ground from the ground stud to chassis ground and without any wiring to the positive stud i have continuity from the positive stud to ground.. just grounded the neg stud to chassis ground.. no other wires are attached to the alts..

frustration factor=High

08-05-2012, 07:06 PM
That doesnt sound right your talking about studs on alt right not field plate studs unground the ground stud and test it inside the alt is a six diode rectifier pack it could be shorted both studs are mounted in plastic houseing that used to hold the stock reg they go throught that and inside the case each stud goes through a heat sink of a diode pack and thats where it picks up its voltage i would test on the resistance scale and see what it reads it may not be a short maybe a resistance through the winding noisemaker may know a little more about this i dont rember if mine do that or not

08-05-2012, 07:07 PM
Do you have on the back a small wire coming out of the alt and bolted to a bolt with a little spade lug?

08-05-2012, 07:16 PM
Try this test on resistance setting in both directions should be open one way and small resistance the other like 5 to 7 range

D-MAX 2112
08-05-2012, 07:33 PM
No spade connection .
im talking about the pos and neg studs on the alts not touching the field plate.. These Leece's. are new.. If i chk continuity just the neg stud to pos stud i get not continuity. If i run from the alt neg stud.. to chassis ground i have continuity direct short/connection between neg and pos stud on the alt. - i dont get it.
Checked between the pos neg both directions..same reading like its a short.

08-05-2012, 08:19 PM
How about no wires hooked up the positive stud to the housing of alternator
Does this show short if so theres an insulator inside by the diode packs that isolates the stud from the case it may be missing do al the units do this or just one of them

08-05-2012, 08:19 PM
Actually to be more specific it insulates the positive diode pack from the case

D-MAX 2112
08-05-2012, 08:36 PM
I called it a night .. i will check further tomorrow after work. I know with no wiring to the pos and neg stud there is not a connection between the pos and neg stud. My 275amp leece doesnt not have this situation..just the 320's

Thanks for you help

D-MAX 2112
08-08-2012, 07:40 PM
Thank you Mr Doughboy!! for your ideas and help.

Ok the mysteries in my mind on Leece Nevilles are no more. Before getting to this point there was a problem when i asked a friend who claimed he "knows leeces" to give me a hand...MISTAKE.. a car battery ..jumper cables and a poof of smoke later!!!!.. Well he knew less then i did!..and after he nuked one of the 320's..i wasnt happy.
So i did some homework called a guy i worked with when i was working at the Prestolite factory few yrs back..He put me onto the "leece guru"... few answered questions and 1 electrical print and 1 mechanical print i was good to go.
I found a great authorized leece repair facility in Garfield Nj... they had the Alt repaired and tested ...in 2 hrs with orig leece parts..
Now understanding /doing.. the conversion from built in reg to external there are no mysteries.. in fact im pretty confident i can answer questions and show someone else how to do it now!!
I was a rough way to learn a lesson ..but guess it goes with the territory.

D-MAX 2112 NJ

08-08-2012, 07:45 PM
So did you get it figured out

D-MAX 2112
08-08-2012, 07:53 PM
Hahaha yes ..so simple a cave man could do it!

D-MAX 2112
08-18-2012, 08:11 AM
All done with the charging system... regulator- external reg conversion... works great. Now i need antenna's..

08-18-2012, 07:32 PM
Love that alt whine right mine sounds like a jet fighter winding up lol

D-MAX 2112
08-20-2012, 10:12 AM
At first i thought the whine was my power sterring pump having an issue!!.. but no.. its the alts.. Cant wait to key this thing down.. gotta get the dual line section setup.. and get a console installed and wired.