spridgets
[Top] [All Lists]

Re: Troubles with Tacho

To: spridgets@Autox.Team.Net
Subject: Re: Troubles with Tacho
From: Greg MAHNEY <mahney@central.murdoch.edu.au>
Date: Fri, 13 Feb 1998 09:31:00 +0800
In-reply-to: <34E32AA7.182165E7@idt.net>
References: <01BD3788.94C106C0.ckotting@iwaynet.net>
Reply-to: Greg MAHNEY <mahney@central.murdoch.edu.au>
Sender: owner-spridgets@Autox.Team.Net
Thanks to all those who have given me advice on this matter.  I'll try them
out  over the weekend and let you know how I go.

The car is Positive Earth so I can rule out that one, sorry I didn't
mention it in my original post.

One thing I'll try is to fabricate a U shaped piece of metal to place on
top of the plastic encased wire between the plastic and the nut - right?
I'll try that first.

Also, can anyone comment on the likely effectiveness of the following TEST
procedure:

1.  Make sure the Tach has got a good earth

2.  Check the Green wire to the spade connector is a power wire

3.  Run a piece of wire from the SW side of the coil (the non-distributor
side) to the small threaded post on the back of the tach, form that wire
into a loop around the post and either hold it there or hold it in place
with a washer and nut.  Run the other end of the wire to the connector on
the key.

4.  start her up and see.

5.  If it doesn't work, reverse the loop, recheck all other conections and
try again

Have I got it right?  Anthing I'm forgetting?

Thanks again to all those who have offered support - it's very dull
(relatively speaking) driving a sports car with no tacho.

Cheers

Greg







 >Chris Kotting wrote:
>
>It's been awhile since I've done one but I think I remember going inside
>and
>having to snip a resistor lead and resolder on another terminal but
>can't give more details.
>I'm sure someone else can confirm whether you need to go inside the tach
>itself.
>I also remember it being printed in an earlier Moss Motors cataogue
>years ago as a
>techtip!
>Regards
>Alan
>
>> Daryl's right.
>>
>> As I recall the change is simply to mount the loop the other way
>> around.
>>  (I.E. Looking at the back of the tach, put a masking tape flag on the
>> part
>> of the wire that leaves the loop to the right.  Turn the loop around
>> so
>> that the tape flag is on the left.)
>>
>> Chris Kotting
>> ckotting@iwaynet.net
>>
>> On Wednesday, February 11, 1998 11:17 PM, Daryl May
>> [SMTP:mayfam@sprynet.com] wrote:
>> > Greg,
>> >
>> > Is the car still positive earth, or has it been converted to
>> negative?  I
>> > am positive that a positive earth tacho will only work on a negative
>>
>> earth
>> > car with some wiring changes, which include changing the white wire
>> loop
>> in
>> > some way.  Sorry if this sounds negative, but it may explain some of
>> the
>> > difficulties (and PO's wiring changes), and perhaps this will need
>> to be
>> > considered in the solution?
>> >
>> > Daryl
>> >
>> >
>> > ----------
>> > > From: Greg MAHNEY <mahney@central.murdoch.edu.au>
>> > > To: spridgets@autox.team.net
>> > > Subject: Troubles with Tacho
>> > > Date: Tuesday, February 10, 1998 6:45 PM
>> > >
>> > > I'm still trying to get the Tacho (it's an electronic one) on my
>> Mk 2
>> > > Sprite to work.  It never has worked in the months that I have had
>> the
>> > car.
>> > >
>> > >
>> > > Looking under the dash there is a spade connector on the back of
>> the
>> > Tacho,
>> > > and a green wire nearby.  I've pushed the green wire onto the
>> connector
>> > > (this seems to tie in with the wiring diagram I've got).  Apart
>> from
>> the
>> > > instrument light there did not appear to be any other connections
>> until
>> I
>> > > started untangling the mass of wires under there.
>> > >
>> > > I then found a white wire which has a loop in it which is totally
>> > enclosed
>> > > in a block of opaque nylon.  Is this the other wire?  Does it
>> connect
>> to
>> > > the other side of the Tacho to the green wire?  Is it a case of
>> putting
>> > it
>> > > on that thin threaded post and finding a small nut to secure it?
>> If
>> so,
>> > > there is no obvious electrical contact, does the thing just sense
>> the
>> > > electrons whipping past (sorry -  I'm a sociologist, not an
>> engineer:-)
>> > ) ?
>> > >
>> > > As you might expect, I did try connecting it but nothing happened.
>>
>>  When
>> > I
>> > > checked that there is a white wire at the coil, there was (on the
>> > oppisite
>> > > terminal to the one which leads to the distributor) but there was
>> an
>> > > additional (blue) wire connected next to the white wire.  It has
>> > obviously
>> > > been added by a previous owner and goes from the coil to thin air
>> near
>> > the
>> > > Tacho.  That is to say, it looks to me like someone tried to
>> replace
>> the
>> > > white wire with this blue one.  In the interests of
>> experimentation I
>> > held
>> > > that (blue) wire to the thin threaded terminal, but nothing
>> happened..
>> > >
>> > > So far I haven't been able to get the Tach out of the wooden dash
>> (see
>> my
>> > > other post today) so I am keen to test the tacho in situ.  Can
>> anyone
>> > tell
>> > > me how to do this please? And/or answer the questions above?
>> > >
>> > > I appreciate the help.
>> > >
>> > > Greg




<Prev in Thread] Current Thread [Next in Thread>