084 TACHOMETER QUESTION

[buster]

Can anyone tell me if this tachometer will work with the 084 engine? It is a Mercury Marine unit, I tried it on the Chev 350 boat and it would not work right.
I would like to know:
#1. What do I hook the "Send" terminal to?
#2. What setting do I use?
Thanks for any helpful info!

Dave[attachment=1:2jbra440]AIRCAT REBUILDING PROJECT 012.jpg[/attachment:2jbra440]

[Duane Scarborough]

Buster,

It's been a long time, but if I remember correctly, on an older conventional ignition you'd connect IGN to the hot side of the coil, SND to the points side, and GND to ground. For a 350 it would be set to 8C/4P. (8 cylinder, 4 pulses per crankshaft revolution) If the 350 has HEI, all bets are off. I think it'd be the same though.

As I understand it, the magneto on the 4A084 either needs to use a mechanical tach as it was designed for, or a tach with an inductive pickup, like the Tiny Tach. Trying to connect an ordinary tach to the P lead of the magneto would probably fry most electronic tachs.

Let us know if you figure out a way to use it though.

Duane

[David]

Piggy back your mag wire on toggle and run it to sender
Set it on 2p 4 cylinder

[Papee]

Piggy back your mag wire on toggle and run it to sender
Set it on 2p 4 cylinder

So you guys have found a tach that will work with the 084? I'm still looking for one other than a Tiny Tach.

[David]

Not sure if that kind will work but the ones we have will work on aircraft and automotive. I dont see why ours wouldnt work on the 084 we just havent tried it on one