6CTA8.3 Erratic Tachometers

[Woody]

Has anyone had problems with engine tachs 6CTA8.3 being erratic, bouncing around. It does it when glendinning engine sync is turned on. Where do the gauges get their feed from?

 

[PMC]

Has anyone had problems with engine tachs 6CTA8.3 being erratic, bouncing around. It does it when glendinning engine sync is turned on. Where do the gauges get their feed from,

Cummins uses a tooth counter on the flywheel. It is a dual pickup, one and set of wires runs the tach, and te others are used in the air heater grid logic circuit.

 

[Woody]

Cummins uses a tooth counter on the flywheel. It is a dual pickup, one and set of wires runs the tach, and te others are used in the air heater grid logic circuit.

Thanks PMC, I'm not near the boat to look. When I look at a generic diagram at Glendinning it looks like the pickups are actually somehow attached to it.

 

[ZZ13]

I believe the auto synch stuff is connected to this mechanical pickup at the front of the engine just under the coolant tank. Or so my pals with rpm synch tell me. I don't have it.

 

[Boatdave]

It could also be that the terminals need to be cleaned up. I had the same issue. Pulled the whole dash panel back and took off the wires, hit them with a wire brush and that fixed my issue. They looked just fine but the clean up helped.

 

[Woody]

Update on my tach problem. The tachs and glendinning are driven as you guys said. A new pair of tachs were installed and problem went away. The tech said in this case it definitely was the tachs.