Tachometer help

[Tkenopic]

Hey everyone,
Today I installed new tach i ordered from Moyer and had it working fine though a bit jumpy especially at idle. I've wired it according to the instructions as well as chatting with Don last week, white wire is to negative side of coil, black to ground, red and green to ignition switched power.

Next i installed new electronic ignition. Black to negative red to positive and now tach is not working. Its intermittently jumping between 0 and 500. Wondering what a possible solution might be? I'd like to time the engine using Thatcth and ndutton method, but really want the tach to be working...

Thanks Trevor

[Al Schober]

Trevor,
My first thought is that you're dealing with corroded wiring and poor connections. Don't know your boat, but is there by chance one of those trailer connectors in there somewhere?
If you wires aren't green and the connections are good, I'll have to rethink. But that's my first guess.

[Tkenopic]

Thanks Al, no all the wiring is brand new, and I've double checked connections. It was working fine with the old points, but not now that the EI is installed...

[ndutton]

Give this a read and see if it helps. You'll need to follow the links too.

http://support.pertronix.com/kb/faq.php?id=34

[Tkenopic]

Thanks Neil,
I did see that, though I was hoping someone here had experience with the issue. I was surprised that Petronix didn't have a more 'formal' fix. Some of those solutions look like trial and error, or a bit of a shot in the dark. I'll call Moyer this week and see if I can get some help there and report back.

[ndutton]

I suggest giving their diode remedy a try. Diodes are cheap.

[Tkenopic]

Canadian Electronics Supply

Anyone in Canada, specifically Ontario have any luck ordering electronics supplies?

Specifically right now I'm trying to track down 10K ohm 1/2 watt resistor.

I've tried The Source, Canadian Tire, Ideal Supply, NAPA without any luck.

thanks,
trevor

[BobMcD]

Trevor,
I see you are in Collingewood.
There is a place called Electronsonics in Markham.
Website

HTTPS://www.e-sonic.com

They have all sorts of electronics stuff.

Bob McD

[ndutton]

Mouser Electronics has a Canadian presence. Here is a 3 watt, 10K Ω resistor:

https://www.mouser.ca/ProductDetail/Vishay-Huntington/ALSR0310K00FE12?qs=%2Fha2pyFaduhKNDu6XUHk%252BQ9wpU3EGPVITRKf3pMww%2Fmnu4POODbrVQ%3D%3D

[Tkenopic]

Thanks for the ideas guys. Nick, being new to this kind of thing, I'm wondering if wattage matters here? The petronix fix suggests 1/2 watt, that one is 3 watt, does that matter?

The resistor is going to be plan B now. Don has received a 'filtering harness' to 'remedy oscillations' from ISSPRO. He's sending that in the mail and I'll wire it up according to the instructions and report back about the progress.

Thanks,
Trevor

[Administrator]

Is this a "one-off" problem or has it been experienced/replicated by others?

Bill

[ndutton]

The wattage specification is a minimum. If the recommended resistor is 1/2 watt, a 3 watt resistor has capacity to spare.

I have a Plan 'C' for you:
Go to an alternator driven tach like the diesels use. That's the type I've always had with no problems.

[Administrator]

Is this a "one-off" problem or has it been experienced/replicated by others?

Bill

If this really is a "one-off," what makes it different from other installs, and why is some additional hardware required in this case but not others?

Bill

[ndutton]

Based solely on the dialog here I think it is a known problem and the entities involved are keeping it quiet. I wouldn't think ISSPRO and Pertronics would have remedies available if it hadn't come up before.

[Administrator]

So Isspro is providing the alleged solution? I thought it was Pertronix who had the mushy explanation and the mushy fix?

Bill