Tach lead - Centech Harness

[mpboxer]

Trying to hook up an electronic fuel pump switch that runs off your tach lead (yellow for Centech); however, I traced the wire and it's not hooked up to anything in the engine bay. It goes towards the distributor and ignition coil, but I don't know where to hook it up. Can I splice it into the green wire with the arrow on the coil that says "Tach" hahaha seems too easy. Just want to be 100% sure when it comes to this and electrical. Thanks guys!

http://i1335.photobucket.com/albums/w663/mpboxer/image1_zpsc55f0daa.jpg


http://i1335.photobucket.com/albums/w663/mpboxer/image2_zps15c16a0f.jpg

 

[mpboxer]

I ended up hooking the tach. lead to the negative side of the coil and all is good. My electronic fuel pump switch from Revolution Electronics works perfectly now.

 

[DirtDonk]

Hey mp, glad you got it working. Sorry I missed this to check it out, but you got it on the money. The Green wire in the old Duraspark "horseshoe" connector is the negative side of the coil and gets the trigger signal to spark from the Duraspark ignition control module.
Without changing the ignition type (say, to an MSD 6al or something similar) that's where your new switch was expecting a signal from anyway. The Centech wires are probably Blue and/or White, so they probably got spliced into the old harness to keep the horseshoe connector.
I always liked those. Looks kind'a cool to me.

I'm gonna have to check out the switch. Not familiar with Revolution Electronics. Is it their product, or do they simply sell other people's stuff?
Thanks for the update and the info.

Paul

 

[mpboxer]

Hey Paul, no prob. Thanks for the reply! Yeah, that horseshoe connector was kind of a pain though. Especially when one of the old crimped/soldered connector comes off.

Below is a link to that switch. I liked it the best over an inertia or oil pressure one. Mainly because of the priming feature. I know it works too because I didn't know the tach wire wasn't hooked up and the engine always shut off about a minute in

http://www.revolutionelectronics.com/Fuel_Pump.html

 

[DirtDonk]

Nice. Simple to hook up too it looks like.
The priming bit is the best feature too I think. A simple pressure switch doesn't usually have that unless you get real creative.

Paul