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Positive to Negative polarity switch

 
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oliver-morrisminor
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Joined: 14 Nov 2005
Posts: 998
Location: Brisbane, Redlands.

PostPosted: Thu Feb 11, 2010 4:16 pm    Post subject: Positive to Negative polarity switch Reply with quote

I am sure this subject has been answered before,
but I have had a look and cannot find it.

So therefore, I ask:

What Proceedure is used to switch polarity from
POSITIVE EARTH to NEGATIVE EARTH....?


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grant69
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Joined: 27 Jan 2004
Posts: 2796
Location: Cairns Nth Qld

PostPosted: Thu Feb 11, 2010 4:50 pm    Post subject: Reply with quote

here we go oliver no point rehashing http://www.morrisdownunder.com/forum/viewtopic.php?t=4497


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DON58VAN
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Joined: 25 Sep 2008
Posts: 863
Location: Sydney/Bowral

PostPosted: Thu Feb 11, 2010 4:51 pm    Post subject: Reply with quote

Hi Oli

I forget where this came from, but it looks right

Step 1 Disconnect battery. Turn it around so that the negative terminal is aligned with the earth strap to the body. Leave disconnected

Step 2 Reverse the ammeter connections. Electric clocks, rev counters and the like may be a problem with polarity so seek advice from
auto electricians if you have these fitted.

Step 3 Swap the leads on the coil, these leads will be marks SW & CB or (+) & (-).

Step 4 Fuel pump, heater fan and wipers are generally not polarity sensitive and therefore should run as normal

Step 5 If a radio is already fitted and is not a valve type, which is not affected by polarity, then change the polarity switch at the back, if fitted to
negative earth. If the radio is a positive earth type then you may have to change one that is negative earth.

Step 6 Change polarity of a generator :-
a) Disconnect leads on regulator "F" and "D"
b) Connect the battery, positive to starter negative to body
c) Stoke the field terminal wire "F" lead across the main battery feed terminal, marked "A" on the regulator. Do this about 5 times at one second intervals creating a spark each time. This will reverse the polarity of the dynamo or generator and is called "Flashing the Poles"
d) Reconnect the "F" & "D" leads to the regulator
e) Start the engine and check the ammeter is indicating the generator is charging correctly

Cheers


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frosty
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Joined: 23 Dec 2003
Posts: 3829
Location: 4559 near a big pineapple, Qld

PostPosted: Thu Feb 11, 2010 5:32 pm    Post subject: Reply with quote

f) .. for fire hose at the ready

Very Happy


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mowog
I can steer now


Joined: 12 Dec 2008
Posts: 160
Location: country WA

PostPosted: Wed Feb 17, 2010 12:04 am    Post subject: Reply with quote

I usually just swap the battery leads over. but radios and alternators if fitted have to be replaced. the regulator will sort itself out after a few minutes. no need to get excessively technical. ignition system is not sensitive either. unless transistorised. also valve radios are sensitive to polarity switch, that is why many have a switch allowing polarity change.


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