1979 Harley voltage regulator

uglyblue66

Subscriber
:shrug:I am stumped.
My dad bought a 1979 Harley Davidson that was a Philadelphia police bike when new. He was told when he bought it about 5 years ago that it had a heavy duty charging system. :shrug: Well there is no charge right now and I tested the alternator coil and it shows good as in the continuity tester beeps.
So we are thinking regulator.
Well, the alternator socket that I stuck the ohm meter probes in was 2 holes, the prongs were on the wire I unplugged.
This is what is stumping me. The regulator that is supposed to fit is apposite. The regulator that is for the 1989 thru 99 EVO big twin is setup like what we have here. So does the newer alternator fit the older engine? or is this thing got a bunch of the wrong parts? :shrug:

Here is what I am referring to.
here is a link to what is called for best I can tell.
https://www.ebay.com/itm/NOS-Voltage-Regulator-RECTIFIER-For-Harley-Davidson-Replaces-74510-75A-Fast-Ship/303023620981

Here is what would fit the motorcycle I am working on.
https://www.ebay.com/itm/Voltage-Regulator-Rectifier-For-Harley-Big-Twin-EVO-32A-1989-1999-Dyna-74519-88/132285849975

And I also notice the dang wires on these are about a mile to long!
 

Ed Radtke

New member
is the bike an flhp? the newer style is probably what fits it because the newer bikes were probly upgraded to the higher outpute alternater already in use for the police bikes
 

uglyblue66

Subscriber
Well I managed to get the 1 that plugged in.But still no chargeing.So even though the coil inside the engine ohmed good,there must be another issue with it.I know the rubber plug is oily so could be a related issue.
 

Tracy T

Subscriber
Did you get it figured out? you should see AC voltage coming out of the charge windings with the engine running and the regulator disconnected, No AC= stator bad or wiring going to it. Also it looks like that regulator needs to be grounded with that 3rd wire that has the ring terminal. I have been thinking of using something like the regulators you linked to on a wisconsin because what was on it is NLA! How many amp is the harley regulator rated for? I also read where the harley guys are using the kohler style regulator $10 range on flebay.
 

uglyblue66

Subscriber
I want to say this new 1 is 35 amp?
No,have not worked on it,my 85 year dad got disgusted and put it in the shed.I can't get my phat rump in the shed between the motor cycle and 5 outboard motors that are hanging on the wall beside it to work on it.I can't ride the thing enough to get it out either.I am thinking the armuture inside is going bad.

As for a regulator.I would try the 1 for the briggs engines,with 2 yellow wires and a red wire. I can't see why it wouldn't work and it is cheap.All it is is a bridge recitfier and some other stuff in a box,it doesnt' care where it gets it's ac from.:shrug:
 

Tracy T

Subscriber
where is it located on a briggs? a neighbor has a riding mower that is junked and told me if it had anything i could use to get it. so i looked but all i seen was two wires coming out from under the sheet metal into a plug.
 

gdstew

New member
uglyblue66----Several years ago at a B & S school, we were told that there was an internal change to that regulator. We were told to run a good ground strap from the mounting bolt to the engine block, otherwise it might not work.
 

ScooterBob

Subscriber
It's been 20 years since I had a Shovelhead, but I seem to remember getting burned once in buying a regulator without fully checking out the stator properly. I saw AC voltage from the stator output, so assumed it was good. The book also says to check with an ohmmeter each output pin to ground, should be open. If you have a partial connection to ground, current will dump there due to bad winding insulation. I have seen one that shorted so good it completely cooked the stator due to the high current being dumped to ground, and you could smell all the burnt windings when removing the primary inspection cover.

Remember guys, once you let the factory smoke out of them wires, you can't put it back in!:bonk:
 

uglyblue66

Subscriber
I will have to get a picture in the morning.it has been a month or 2 since I worked on this and it may as well be 10 years with my short memory.
BUt i do know there was a rubbery thing that the plug went into that was just barely sticking out of the "engine".It was oily to.
The regulator is mounted on the frame right in front of the base of the engine..I will get pic or 2 tommorow.It may be noon or after.
 

gootsch

Member
Take the regulator off and see if there are any numbers on the back of it. If there are, feed them into e-bay and see what comes up.
 

uglyblue66

Subscriber
Thanks giving has had the past several days jumbled for us,but 1 day early next week,the printed off paper work and my vom will be in the shed and I will be working on this to see what is going on.
He keeps me busy on something about all the time. This morning it was the satalite radio in 1 of his trucks buzzing. :crazy: Got that fixed finally.
 
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