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RE: [TR] TR3A distributor help needed

To: <triumphs@autox.team.net>
Subject: RE: [TR] TR3A distributor help needed
From: "Randall" <tr3driver@ca.rr.com>
Date: Sun, 19 Nov 2006 22:08:18 -0800
> When I connect my VOM to the neg (neg ground remember) wire  to the
> dizzy and to the block and crank, the ohmmeter stays pegged all the
> way  and does
> not bounce as one would expect as the points open and close.

Are you saying it indicates zero ohms, or infinite ohms ?

>  When  I
> inspected the new points there is no apparent short, and when I put
> one  VOM contact
> point on the white wire/condensor post

I don't understand ... the white wire should go to the + terminal on the coil,
not the condensor.

> and the other one on the  spring and
> manually open and close the points it does just what it is supposed
> to do when
> you crank. The ohmmeter needle bounces from one end of the scale to
> the other,
> indicating there is no short in the points.  What am I  overlooking?

Sounds like there is not a good connection between the negative post on the
coil, and the points.  That would mean the wire from the coil to the dizzy, or
the connection through the side of the dizzy, or the lead from the side of the
dizzy to the points.  It's not uncommon for these wires to fail internally and
not show a problem outside (because of the constant vibration and flexing).
Note that the lead inside the dizzy is a special kind of wire to handle the
constant flexing ... if someone has replaced it with ordinary stranded wire then
it's very likely that is the problem.

There is also a special wire lead that connects the point plate to ground, which
might be open, disconnected or missing entirely.

So, turn the engine until the points close, and turn the key on.  Because of the
problem I think you've described, there will still be 12v on the negative
terminal of the coil.  Follow the wire to the points with your voltmeter,
looking for where it becomes 0v.  You've just crossed where the problem is.

If the points also have 12v on them, then it's the ground lead.

Randall


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