sw tach/6al/painless wiring how to? Help

[nymathboy]

Hey guys,

I have a SW Tach, a painless harness and a MSD ignitiion box.

I am trying to get my tach wired up correctly. Any suggestions?

[Tom Wells]

nymb,

Try looking here: http://www.google.com/search?q=stewart+warner+tachometer+msd+wiring&ie=u tf-8&oe=utf-8&aq=t&rls=org.mozilla:en-USfficial&client=firefox-a

There are some pdfs near the top that cover your question!

Tom

[nymathboy]

I clicked on the links on the whole page and all of those instructions provide for color coated wires coming off of the tach.

My tach has no wires coming off of it except for the black one which is for dash board lights.

[nymathboy]

I now have the purple wire in the picture going to the SIG post.

In the engine bay I have the purple wire going to the negative on my coil.

I have a keyed positive power wire going to the POS terminal

I have a ground wire going to the NEG terminal



When I turn my car on I can tell that the tach is getting power because I see the needle move but it never gets past zero. The needle moves to zero and stays there even if I rev the engine.

[nymathboy]

I figured it out.

First. give up on the idea that you can hook up your tach to the coil. I tried it several different ways. I even called up SW and they said that with certain coils you hook up the SIG post to the + side of the coil which I never heard before. I always heard that you hook up the SIG post to the negative side of the coil.

For what it is worth here is how it is done:

1. Make sure the pins on the back of the TACH are set up for a V8 engine.
2. If you have a MSD 6AL ignition box, there is a male spade connector on one end of the MSD box. Hook that directly to the SIG post on your tach.
3. The AUX post is not used
4. Connect the NEG to a good ground
5. Connect the POS post to terminal at your key switch which will remain hot when you turn your engine on. This is easy if you use a test light to figure out which is hot at the key.

[thatbluetruck]

I had a tach like that and it shorted out while driving home from work on day, smoke from behind the dash and a section of group wires melted together. Corrected the damage and made a few changes. I ordered another one of those famous tachs and and it would not work. I will try the suggestions. Thanks

[nymathboy]

It doesn't help their image that it has a "made in Mexico" sticker on the side.

I can't complain. I had it wired up wrong a few times and that should of fried it. Now it works just fine.