Wonky tachometer question...

proffsionl

2007 350EC, twin Merc 350 MAGs.  Starboard tach is bouncing a lot.  Tried tapping the gauge, think it might be a bad ground.  Where would I continue to look for this ground (or the sending unit on the motor)?  I have pulled the dash and everything is very clean, no corrosion.  Pulled the connectors on the gauge, everything is very clean and good.  

Any thoughts?  

Thanks!

aero3113

There is a switch on the back of the gauge for 4,6 and eight cylinders. Try moving the switch back and forth a couple of times.

mattie

Little bit of levity for a wonky tach. Ages ago we put a bunch of foil wrapped Taco Bell chili cheese burritos on the intake to keep them warm. That certainly made the tach jump all over the place.

Black_Diamond

Faria tach?  If so: that is the problem. 😂

proffsionl

Yes, I know the Faria tachs are garbage.  I'm still hopeful, though...   

MarkB

Faria tachs are known for that.  As aero3113 says, try moving the pin in the back and forth, and put it back in the right setting, then see if it settles. Ohterwise, get yourself some better gauges!

Stodge

Or just switch to vessel view and eliminate the gauges all together.

MarkB

Or put in a Smart Craft system, but not sure what the interface is with that 2007 engine (even for vessel view) ... is their an analog to digital harness needed?

Ian

It like has an SC plug like my 2003 but not implemented so easy to add VVM.

proffsionl

shawnmjr said:

mattie said:

Little bit of levity for a wonky tach. Ages ago we put a bunch of foil wrapped Taco Bell chili cheese burritos on the intake to keep them warm. That certainly made the tach jump all over the place.

Why did they stop making the chili cheese burrito at most locations? Man those were good. 

I was always partial to the Enchirito...