Speedo and SpeedSet Calibration

[Weil Thing]

Hello, all, I hope someone can help me with his. Since having my 3rd triducer out in under warranty, my boat speedo is off 5 mph. Can anyone shed light on how to calibrate this?

Also, my SpeedSet is sometimes +/- 3 mph! Is there a way to adjust this? It used to be much tighter than that. Any help is greatly appreciated!

[worsty]

I only know about the Mercury SmartCraft calibration procedures, but there usually is a set point or transition speed setting. This is where the speedo switches from the paddlewheel/pitot sensor (slower speeds) to a GPS scource or other input sensor (higher speeds). If you have a paddlewheel and the speedo uses that sensor ALL the time, it will be off, especially at the higher speeds (usually 10-15 Knots and higher). GPS is the best and most accurate speed source, so if you do have that as an option to use, use it! Set the transition speed at 5 Knots/MPH, this way paddlewheel/pitot will be used at very slow speeds and then accellerating over this value the speedo will switch to the GPS.
Somewhere in your owners manual find that calibration procedure. It most likely will have you "Cal" the correct frequency or speed to that paddlewheel. Having the boat moving thru the water at a slow steady speed, you input or +/- the current seting to adjust the speedo reading. If you have another boat next to you with a GPS calling out the speed is best to set this. Or borrow a car GPS. Just becareful and have help with you so that you are not doing 20 things at once and not paying attention to your driving duties.
The SpeedSet is totally unfamiliar to me, but there could be a "gain" setting that when adjusted will bring that +/-3 MPH lower.
Good luck, sorry if I did not fully answer your question or if I totally missed it. I have a 2004, so I do not have the nice fancy helm gauges from PCM/Faria like you do.