I forgot to mention that I DID have to work the electric tach after the
conversion to
keep it from cooking. There are books that cover the internal wire switching in
depth. Brad
Robert Rees wrote:
> FWIW, I converted a 65 Midget over to Negative earth from Positive earth and
>all the
> gauges continued to work with no ill will. But I don't have a clock, the cars
>are
> supposed to run "healthier" with them being Neg. earth ( according to a Brit
> mechanic who helped me through the process). My .02 Brad
>
> corcoran wrote:
>
> > This is a multi-part message in MIME format.
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> >
> > --------------CA47FCFEC7009BF478BA4F43
> > Content-Disposition: inline
> >
> > X-Mozilla-Status2: 00000000
> > Message-ID: <38D19591.BDEC70DE@bainbridgeisland.net>
> > Date: Thu, 16 Mar 2000 18:16:49 -0800
> > From: corcoran <corcoran@bainbridgeisland.net>
> > X-Mailer: Mozilla 4.7 [en]C-CCK-MCD NSCPCD47 (WinNT; U)
> > X-Accept-Language: en
> > MIME-Version: 1.0
> > To: sidney raper <spl310@hotmail.com>
> > Subject: Re: Three seater on ebay
> > References: <20000317000446.27491.qmail@hotmail.com>
> >
> > Sidney,
> > What I mean to say is that if the gauges on a '64 1500 are connected
>backwards
> > they won't fry. When troubleshooting electrical problems I've swapped the
>leads
> > on the meter wires back and forth several times and they don't appear any
>worse
> > for it. The temp meter is just a bi-metalic lever wrapped with heater wire
>that
> > bends with increasing current which swings the needle. In other words it is
>a
> > resistive circuit that does not respond any differently when reverse
>polarized.
> > (note: '63 and '64 1500's use a unique temp sender although that is not why
>they
> > won't fry). The clock appears to be the similar "technology". I think later
> > (1600's?) have a similar gizmo that I think is used to stabilize instrument
> > power. The fuel gauge is a real meter I believe so it's not true that it's
> > resistive. It will peg the needle the wrong way if you reverse polarize it
>but
> > not fry. The tach and speed are mechanical. Light bulbs are also resistive
> > elements.
> > I don't know about '65 1500's, 1600's or 2000's. Most likely not.
> > Now I've never, ever reverse polarized the entire car! I just remember that
>the
> > battery lead that goes away from the engine towards the rear end ,is ground
>is,
> > positive, and goes to the (+) ;-).
> > 20+ years ago I used to try and run a negative ground cassette player by
> > isolating it's chassis from the car frame but sooner or later it would
>contact
> > and it was not a pretty sight. In fact I think I blew up 3 of them that way!
> >
> > regards,
> > Tim C.
> > 2 '64 1500 Fairladys
> >
> > > Tim,
> > >
> > > Pardon my ignorance, but you confused me. Do I understand this to mean
>that
> > > there would be NO problems?
> > >
> > > Sid
> > >
> > > >From: corcoran <corcoran@bainbridgeisland.net>
> > > >Reply-To: corcoran <corcoran@bainbridgeisland.net>
> > > >To: Mark van der Hoek <captainhoek@postmark.net>
> > > >CC: datsun-roadsters@autox.team.net
> > > >Subject: Re: Three seater on ebay
> > > >Date: Wed, 15 Mar 2000 19:08:02 -0800
> > > >
> > > >Mark van der Hoek wrote:
> > > >
> > > > > Dan Zubkoff wrote:
> > > > >
> > > > > > The speedometer,
> > > > > > tachometer are missing the cables. The owner said the temp/fuel
>gauges
> > > > > > work...but they didn't appear to be working. The car has been
> > > >converted to
> > > > > > Positive ground. The radio is original but doesn't work.
> > > > >
> > > > > <snip>
> > > > > > Also the car's heater is currently inoperable.
> > > > > >
> > > > >
> > > > > Some or all of these problems MIGHT be caused by a botched positive
> > > > > to negative ground conversion. IF that is the case, the radio is
> > > > > history, as are the guages and maybe the speedo/tach. "Why?", you
> > > > > ask? Get the wires crossed and you can have current flow through the
> > > > > tach/speedo cables, looking for ground. Heat 'em up, melt 'em down,
> > > > > throw 'em out! The owner may not even realize why they aren't
> > > > > working. The radidio is especially likely to have been smoked. To
> > > > > convert the ground and still use the original electronics you must
> > > > > completely isolate the instrument (whether radio, gauge, or
> > > > > whatever)from the car chassis.
> > > >
> > > ><snip>
> > > >
> > > > > Caveat Emptor
> > > > >
> > > > > Mark van der Hoek
> > > >
> > > >Reverse polorizing the gauges on a 3 seater 1500 won't effect the gauges
>at
> > > >all.
> > > >Everything is resistive, even the clock.
> > > >It would let the smoke out of the radio and charging circuit. The heater
> > > >motor
> > > >might spin backwards. Note: stock 1500's
> > > >are positive ground.
> > > >
> > > >Tim C.
> > > >2 '64 Fairladys
> > > >
> > > >
> > > >
> > >
> > > ______________________________________________________
> > > Get Your Private, Free Email at http://www.hotmail.com
> >
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