HILLMAN CAR CLUB
OF SOUTH AUSTRALIA INC

Tech Tips:
Polarising a Generator
HILLMAN CAR CLUB
OF SOUTH AUSTRALIA INC



From: Vic Hughes [v.hughes(at)austarmetro.com.au]

Now I have to find out why the charge light stays on all the time, and what has happened to reverse gear....  I know it was there before I pulled the gearbox out so who has stolen it

Vic



From: Alkon [alkon@bigpond.com.au]
Sent: Sunday, March 16, 2003 7:54 PM
To: Vic Hughes" [v.hughes(at)austarmetro.com.au]

Hi Vic

Others have suggested who stole your reverse gear.  But who wants to go backwards?? :))

Generator problem??  I assume generator.  solution 1, throw it out and fit Holden alternator :))
Solution 2: pull off generator, dismantle, polish commutator with fine wet & dry paper.  Reassemble and all should start happening.  May also need to be repolarised as has been sitting for long time.  Just remove fan belt and push down cut out so it motors for a few seconds.

Keith
55 Californian



From: Vic Hughes [v.hughes(at)austarmetro.com.au]
Sent: Thursday, March 20, 2003 9:12 PM
To: Alkon [alkon@bigpond.com.au]

Hi Keith,

Not a generator problem as that has been reconditioned, so I'm going to work on the repolarizing theory.

If I could just clarify your advice
"Just remove fan belt and push down cut out so it motors for a few seconds".
Are you saying ; with the fan belt off, run the engine and push down on the voltage regulator cut-off"
Sorry to be so obtuse but I'm electricaly challenged, still can't figure out where all those electrons go to :)

Thanks mate

Vic



From: alkon [alkon@bigpond.com]
Sent: Friday, 21 March 2003 11:07 AM
To: hillmanlist

This message forwarded by the Hillman List.

Hi Vic

I will run through the whole proceedure step by step.
Assuming the engine and accessories are all connected ready to run:

1 remove fan belt

2 lift off cover on voltage regulator box and push down cut out relay.  (This is the one with only one winding) If you push the other one no damage will occur and nothing will happen.  The generator will start to rotate, let it go for 30 sec or so, not critical, and then release the cut out.  If it sticks down just flick it up with a finger nail or a small screwdriver under the armature (the metal bit you pushed down)

3 If all the above has occured then refit the fan belt and start the engine, and it should charge OK.

If the generator doesn't rotate when pushing the cut out down then you have a wiring problem.  Check the D terminals on the regulator and the generator are connected and that the F terminals are also connected.  Even if the generator has been overhauled it is possible for oxide build up on the commutator surface to prevent charging.  Polishing the commutator with fine wet and dry and wiping it off with a rag wet with metho is a quick clean up.

As you confess to being electrically challenged, the following tester is a good device.  Take a 12 volt tail light fitting and fit longer wires to it with small croc clips on the end.  Clip one wire to battery ground/earth/body and the other to wherever you are looking for power.  Test it by touching the hot side of the battery.  Lamp lights to show volts.  This device works with both negative and positive earth systems :))

With this "sophisticated" tester you can check the regulator box for correct connections.
Do these tests with engine off and fan belt removed.
Touch test clip to A and A1 in turn the lamp should light indicating power is reaching these points.
Touch test clip to F and lamp should light when cut out is pushed down
Touch test clip to D and lamp should light when cut out is pressed down
If the lamp lights when testing F and D then the regulator box is connecting correctly :)
Repeat the tests on the F and D terminals on the generator.  If it shows power at these terminals and the generator does not rotate the problem is in the generator.  If there is no voltage at these points then the problem is either the regulator box or the wiring to the generator.
One area that can cause connection problems is the crimp conectors used today.  They just wrap around the wire and are crimped or squashed tight.  Add loose plus oil plus heat and we get no electrical connection even though it all looks well attached.  The only solution if you have no soldering gear is to cut off the offending connector strip back the insulation and fit a new connector.

In the handbook there is a whole lot of stuff on cleaning generator armatures and mention is made of "undercutting" commutator segments.  You don't need to do this but after cleaning the armature with the fine wet and dry what I do is scrub off any residue from the commutator with a toothbrush and a small amount of metho.  Metallic conducting deposits or carbon build up between the armature segments can leak away the charge current and cause a not-charging situation.
Generators are simple and robust and despite the noises made by the pro-alternator faction are a reliable source of charge for the battery.  They do require periodic attention to brushes and regulators as these are mechanical switching devices.

The test lamp is better than using a test meter for most of the electrical tests we do on cars.  Test meters can give results that lead us astray.  Electricians use test lamps extensively for testing 240 volt and 415 volt circuits because of the unambiguous results they give.

Keith
55 Californian



From: Vic Hughes [v.hughes(at)austarmetro.com.au]
Sent: Saturday, 22 March 2003 9:57 PM
To: hillmanlist

Hi Keith,

Hey, repolarising worked!  :)   Charge light varies in intensity and goes out at 1200 rpm although it comes on again at higher revs.  I figure that I now just have to adjust the regulator.  Have the manual and a multimeter so hopefully can adjust the regulator and cut out screws accordingly.

Thanks for the help

Vic



From: alkon [alkon@bigpond.com]
Sent: Sunday, 23 March 2003 11:07 AM
To: hillmanlist

This message forwarded by the Hillman List.

Hi Vic

Glad to be of assistance.
The charge light will start off bright and should gradually dim as generator voltage increases with engine rpm.
It should go out fully when the generator voltage reaches the cut out setting.
If it comes on again do not adjust the regulator, it is not faulty.
The cut out contacts are just dirty.
Clean them with fine wet and dry and try again.  The reason the generator light comes on again as revs rise is the cut out contacts are not closing electrically.  The relay may be pulling in but not making good contact electrically.
This would give flat battery if you used the headlights as the charge rate would be limited.

Keith
55 Californian



From: Vic Hughes" [v.hughes(at)austarmetro.com.au]
Sent: Sunday, 23 March 2003 11:30 AM
To: hillmanlist

Funny you should say that Keith, I was looking at it this morning and noticed the cut out points were sticking and appeared dirty.........

... (snip) ...

Vic


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