One wire alternator

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bobv
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Joined: Sun Jul 13, 2014 4:31 am

One wire alternator

Postby bobv » Sat Aug 11, 2018 9:04 pm

Anyone using the one wire alternator? Ihave had many of these fail.I have three in stock not working. I found a u tube on exciting a one wire alternator.
I tried this and it worked my alternator charges fine now. the other two I have probably have the same issue. Beats buying a new one.I had to cut a small hole in the cover to access the r terminal a sillicon sealer with a small patch will close the opening back up.It appears that if these alternators sit for a time they need to be excited.
Bob

EWRice
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Joined: Thu Feb 04, 2016 12:37 pm

Re: One wire alternator

Postby EWRice » Sun Aug 12, 2018 8:37 am

You must have the old style 10SI se alternators. I have never heard of having to manually excite one. I know that all of the one wire alternators being sold today are using AC activated regulators. This means that they self excite at very low rpm almost instantly. They were originally created for the antique tractor guys.
Muskegon Lake
1972 32' Express flybridge
"AL13"
Twin 318s
On board air & prime 920
1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson

bobv
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Posts: 32
Joined: Sun Jul 13, 2014 4:31 am

Re: One wire alternator

Postby bobv » Mon Aug 13, 2018 6:21 am

Nope they are the new style. If they sit too long they loose charge and you need to excite them. This thing would not work at any rpm. I jumped it to the battery and in couple of seconds it was charging. I didnt use the boat last year one stayed working. The other wouldn't charge.
Bob

Tuggle
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Posts: 110
Joined: Sun Jun 26, 2016 4:42 am

Re: One wire alternator

Postby Tuggle » Mon Aug 13, 2018 11:19 am

Replaced both of mine last year with Arco's, wired them directly to the positive battery lead, they've never missed a beat.
"Deplorable", 1975 32' Express, Twin 318's, Raw Water Cooled, Lake Lanier, Ga.

EWRice
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Posts: 251
Joined: Thu Feb 04, 2016 12:37 pm

Re: One wire alternator

Postby EWRice » Mon Aug 13, 2018 9:36 pm

I think you have a defective regulator. I worked at a starter/alternator shop for five years. We built many different custom 1 wire alternators and I have never seen one have to get excited to work, with one exception: some battery isolators will screw with a one wire alternator. The only piece of charging equipment we ever had to excite (polarize) was a DC generator.
Muskegon Lake
1972 32' Express flybridge
"AL13"
Twin 318s
On board air & prime 920
1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson

Tuggle
Aluminum Star
Posts: 110
Joined: Sun Jun 26, 2016 4:42 am

Re: One wire alternator

Postby Tuggle » Tue Aug 14, 2018 5:16 am

On a one wire alternator isn't the voltage regulator internal, thus completely bypassing any external regulator?
"Deplorable", 1975 32' Express, Twin 318's, Raw Water Cooled, Lake Lanier, Ga.

EWRice
Royal Aluminum Star
Posts: 251
Joined: Thu Feb 04, 2016 12:37 pm

Re: One wire alternator

Postby EWRice » Tue Aug 14, 2018 12:27 pm

The voltage reg is internal. It is inside the back cover.
Muskegon Lake
1972 32' Express flybridge
"AL13"
Twin 318s
On board air & prime 920
1963 Thompson Super Sea Lancer
Graymarine 327
1961 Alumacraft 12'
'55 10hp Johnson