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Re: [Healeys] Points question..

To: Healeys <healeys@autox.team.net>
Subject: Re: [Healeys] Points question..
From: mike brooks <hypercubic@yahoo.co.uk>
Date: Sun, 10 Apr 2011 23:27:19 +0100 (BST)
Bob,
You are correct that putting a diode across ignition points wouldn't
work, but 
your reasoning about high voltage is incorrect - ignition points
break the low 
tension 12v primary circuit not the high tension secondary
circuit, whose 
voltage travels from the coil secondary, via the distributor
centre core and the 
rotor to each spark plug in turn.

Mike Brooks
'56 BN2
Scotland


From: Bob Spidell <bspidell@comcast.net>
Subject: Re: [Healeys]
Points question..
To: Tom <ah3000me@gmail.com>
Cc: healeys@autox.team.net
Message-ID: <4DA1D3DA.8040502@comcast.net>
Content-Type: text/plain;
charset=ISO-8859-1; format=flowed

AFAIK, points are made of solid tungsten
(although, with our 'cheap at all 
costs' society that may not be true any
more).  Theoretically, you can file them down to almost nothing (but I
wouldn't).  Filing of points is mostly to get you 

home, where you can
install a fresh set.

The condensor--it's a capacitor--is an integral part of
the primary ignition 
system.  It affects the way the coil is 

charged and
discharged, though I don't have the knowledge to totally explain it 
(in
electronics it's known as a 'TC 

circuit').  The points in the fuel pump are
just used as an on-off switch; 
timing isn't critical.  The diode is known as
a 'flywheel diode' because it shunts the back-current induced when the
electromagnetic field in the pump body 

collapses.  Come to think of it, if
you put a diode across the ignition points 
the 'back-current' from the coil
would 

flow through them instead of providing a spark  at the plugs (and the
diode 
would burn out the very first time, since 

there isn't a diode made
that can withstand 20K volts or more that I know of).
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