Tech Tips:  Fitting an Alternator

From: Gary Grainger [gary(at)featcovers.com]
Sent: Saturday, 1 November 2003 6:14 AM
To: hillman@can-inc.com
Subject: "Hillman - " change of electric system - advice needed please

This message forwarded by the Hillman List.

As winter draws on (you have got yours on haven't you?), I feel that I would benefit from upgrading the electrics on my 66 super minx estate.
My research tells me that I can replace my Lucas dynamo with an alternator, and that alternators from several cars will fit.  Which ones?  And what else do I need to change?  On a scale of 1-10, where changing a tyre is 1 and changing an engine is 10 (I've done both), where does this upgrade rate?
Does it mean that I will be able to do something about the feeble and unintentional intermittent wipers too?

Gary in the UK
Super Minx Estate 1966

From: Vic Hughes [v.hughes(at)austarmetro.com.au]
Sent: Saturday, 1 November 2003 8:13 AM
To: Gary Grainger; hillman@can-inc.com
Subject: Re: "Hillman - " change of electric system - advice needed please

This message forwarded by the Hillman List.

Hi Gary,

There's quite a good article on converting an Alpine to Alternator on the Classic Sunbeam site:
From the home page, click on 'Back Issues' and then click on 'January 1999' at the top of the list.  You'll need to scroll down a bit on the page that comes up from that link.

The process should be quite similar for a Super Minx



From: Keith Johnson [keiths55(at)bigpond.net.au]
Sent: Saturday, 1 November 2003 8:53 AM
To: Gary Grainger
Cc: hillman@can-inc.com
Subject: Re: "Hillman - " change of electric system - advice needed please

This message forwarded by the Hillman List.


The easy answer is to get a suitable alternator with inbuilt regulator.  Here in Australia Holden (GM) ones work great.  You need to fabricate a suitable mounting as the alternator mount is shorter, I have just done the bottom mounts on a length of threaded rod through the original generator bracket.  This allows an amount of fore and aft adjustment to get the pulley aligned.  Then it is just a matter of getting a suitable adjuster piece for the top mount.

The wiring is very simple with this sort of alternator.  One heavy charge wire from the big "+" terminal to the battery (the inbuilt diodes do away with a need for a mechanical cut out relay) and the "ind" wire which connects to the wire running from the "ign" warning light to the control box.  I have a wiring diagram of the changes which are far simpler to do than to describe.  I last did this on a '67 Hunter but the control box is the same through the whole range.  I wrote it all down as I had the thought that somebody would ask just this question some time :-)

Once the alternator is mounted the rest is only a few hours work allowing for refreshment stops :-))

Do it my way and people would never know it wasn't a factory job.

55 Californian

Editor's note: Keith has promised to send me the diagram (for a '66 Hunter) when he gets time to scan it.

From: Simon Hilton [Simon.Hilton(at)btinternet.com]
Sent: Sunday, 2 November 2003 6:21 AM
To: Keith Johnson; Gary Grainger
Cc: hillman@can-inc.com
Subject: Re: "Hillman - " change of electric system - advice needed please

This message forwarded by the Hillman List.

In Britain, Lucas ACR alternators are readily available and the easiest route is to use the mounting bracket/alternator/fan belt/adjuster off a late Commer PB this all bolts straight on, follow Keith Johnson's wire linking on the control box (I soldered straps behind on mine so they don't show) and the job's complete.

More than a year later, another version of the discussion begins

From: Russ Maddock [sunbeammadd(at)yahoo.com]
Sent: Tuesday, January 04, 2005 9:18 PM
To: Hillman List
Subject: [HillmanCars] alternator

I've decided the time has come to fit an alternator to my Husky roadster.
(Light-hearted reference to Sunbeam Alpine there ... Ed.)
Has anyone any recommendations on a model of alternator or donor car that is readily available in Australia?  That pretty much rules out any American makes of car.

I want one with a built in regulator.

Someone has already suggested an (Australian) Valiant unit might be a suitable choice.  That idea appeals to me because I have a client who is a Valiant specialist.


Russ Maddock

1963 Sunbeam Alpine sIII
1969 Sunbeam Imp Sport
2001 Peugeot-UK 206 1.6
2002 Subaru Impreza (Hers!)

From: Wendy or Glen Davies [wlwk_11(at)hotmail.com]
Sent: Tuesday, January 04, 2005 10:57 PM
To: HillmanCars@yahoogroups.com
Subject: RE: [HillmanCars] alternator

Russ, can add from my end that those Chrysler/Valiant alternators/regulators were great in the 7+ cars I was owner or mechanic of.  Never did have a single problem with any of them.  Couldn't give you a parts #, but they were all from late 60's to early 70's, all w/slant six's.  I put >200k miles on 2 of 'em.  Drove one 7k miles round trip from N Calif into Mexico.  Hope you can find they'll fit, etc.

Jus' remember they're hot in the back!!


From: Russ Maddock [sunbeammadd(at)yahoo.com]
Sent: Thursday, January 06, 2005 3:27 PM
To: HillmanCars@yahoogroups.com
Subject: Re: [HillmanCars] alternator

... (snip) ...

I went to see my Valiant contact.  The alternators he showed me looked about right but I had doubts about the pulley.  It seemed to be designed for a wider fanbelt than the Rootes pulley and I imagine that's not a good thing.

I might chat to a sparky I know.


From: Keith Johnson [keiths55(at)bigpond.net.au]
Sent: Thursday, January 06, 2005 5:42 PM
To: HillmanCars@yahoogroups.com
Subject: Re: [HillmanCars] alternator

I have a Holden alternator attached to my 1725.
It works, the pulley matches and I can get replacements from any of the traditional landowners when out of town :-)

Needs one wire to the battery positive (hot side) and one to the charge indicator light.

I must finish a conversion wiring diagram I promised about a year ago.  I should join "procranstinators anonymous"


From: Chuck Hillman [hillmanminx(at)hermon.net]
Sent: Saturday, January 08, 2005 11:11 PM
To: HillmanCars@yahoogroups.com
Subject: Re: [HillmanCars] alternator

Hi Vic,

        One of my Minx has a Bosch alt from a water cooled VW, another one I installed a GM alternator with the external regulator up where the Lucas one was.   This is a nice upgrade, and doesn't hurt the restorability of our 'valuable prestigous motorcars'.


From: Keith Johnson [keiths55(at)bigpond.net.au]
Sent: Sunday, January 09, 2005 12:49 PM
To: HillmanCars@yahoogroups.com
Subject: Re: [HillmanCars] alternator


I use the one used on HQ - HZ Kingswood.  They also polish up nicely :-)


From: Al Savage [asavage(at)iname.com]
Sent: Sunday, January 09, 2005 6:39 AM
To: Hillman at Yahoo!
Subject: [HillmanCars] Re: Alternator conversion

(Referring back to the original question from Russ)
This is probably less than useful, but . . .

Years ago, I was conversant with the pre-internal-regulator Delco alternators, common to about 1972 and older GM cars in the States. I had a stack of them and used to rebuild them.

The positive and negative diodes are physically interchangeable so pressing them out of their respective heatsinks and pressing them back in opposite locations effectively converts them to positive ground operation. They require the external regulator though, because only the external regulator is tolerant of reversing the polarity: no semiconductors!

This worked very well for me (in my '60 Husky, 1390cc) for a number of years. Though that series of alternators were available in many different output capacities (35a to about 63a), the differences were entirely in the rotor, all the other components were nearly identical. I used the smallest rotor (35 amp) so that full loading of the alternator would affect the engine's output the least.

Later, I discovered that nearly everything on the Husky would work as well using negative ground, including the windscreen motor, the temperature and fuel gauges, and the starter, so I installed a different Delcotron (internal regulator S10 model) and went to negative ground.

Al S.

From: Keith Johnson [keiths55(at)bigpond.net.au]
Sent: Sunday, January 09, 2005 12:44 PM
To: HillmanCars@yahoogroups.com
Subject: Re: [HillmanCars] Re: Alternator conversion

Converting to negative ground is a good option. You can do it with the original generator as well. (see on the HCCSA webpage)
referring to the top section of this page ... Ed.
However apart from reversing the coil connections bear in mind that the wiper motor now runs the other way.  It still pushes the wipers back and forth but you will find it will park in the wrong place.  I haven't researched the fix for this yet but you can readjust the park switch easilly enough.  The wires connected to the brushes could be reversed which would make it run in the original direction again.

The upside is you can use all the cheaply available radio/sound systems and electronic gadgets.


From: Peter Chadbund [peter(at)thecopshop.co.uk]
Sent: Thursday, January 20, 2005 3:16 AM
To: HillmanCars@yahoogroups.com
Subject: "Re: [HillmanCars] Re: Alternator conversion

Hi guys, just sitting here pondering the meaning of life and thinking I'll do an alternator transplant on my Husky when it's all back together, but just pondering why the gauges still work ok, without swapping connections or something, as they are only moving coil devices after all, and the current through that coil will be travelling the wrong way.  Or am I missing something (as usual!)


From: Keith Johnson [keiths55(at)bigpond.net.au]
Sent: Sunday, January 30, 2005 8:08 PM
To: HillmanCars@yahoogroups.com
Subject: Re: [HillmanCars] Re: Alternator conversion

Starters, generators and instruments are unaffected by polarity.
The starter is the easiest one to describe.  The current through the fields reverses when you change to negative earth, but so does the armature.  So the end result is the same relationship as before.  Wound field type motors are often called universal motors as they will run on AC as well as DC.

The wiper motor on the other hand has permanent magnet field so it will reverse rotation when polarity change.  This doesn't affect operation but does put the auto park off a bit as it is going the other way.  Either adjust the park switch or get technical and reverse the internal wiring connections to the brushes.

I have a feeling that the fuel gauge is electro thermal in operation so this is why it is also unaffected, i.e. the tank sender varies the current and the indicator deflects from the heat it generates.  This also makes it slow acting so it doesn't flick around the place.


From: Jan Eyerman [jan.eyerman(at)usa.net]
Sent: Monday, January 31, 2005 6:41 AM
To: HillmanCars@yahoogroups.com
Subject: Re: [HillmanCars] Re: Alternator conversion

The fuel and temperature gauges in the Audax cars are NOT bi-metal gauges.
They are a unique Smith's voltage difference measurement gauge.  They measure the difference in voltage between the "hot" lead and ground and the "hot" lead and the resistance unit in either the tank or cylinder head.  This is done by using two coils in the gauge working against each other instead of one coil (as is used in most non-bimetal gauges).  This allows the gauges to work correctly (more or less) independently of the actual voltage in the electrical system-eliminating the need for a voltage stabilizer (or regulator).

Jan Eyerman

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