I recently added Merc's VesselView...

[BillS]

I recently added Merc's VesselView mobile to my 2015 19 SPX with the 220 HP engine. There is a significant discrepancy between the boats tach and the RPM reported by VesselView. At idle the Tach shows around 900 RPM and VesselVeiw shows about 620. At 4,000 RPM on the Tach VesselView only shows about 2,830 RPM. I suspect the engine selector switch on the tach was set incorrectly at the factory. Removing the tach by accessing it from under the dash looks difficult. Does anyone know if there is another way?

Thank 

[tolatron]

I had the same issue with my 2019 230 SPX OB. I had to remove the tack and set the switch to the proper setting. It seems the factory takes them out of the box and installs them with no attention to adjustment to the proper setting.

[BillS]

Thanks for the information. I found a photo of the back of the tach on the manufactures web site and after seeing the location of the switch was able to set it for a 6 cylinder engine without removing the tach. The switch is largely covered by the tach's mounting bracket but on the 19 SPX it can be set with a screwdriver from under the dash.