Trim gauge calibration

[donaldboyer]

Mercury 90hp
3cyl 2 stroke
s/n 0b312461
Excellent condition

The trim gauge on this motor has become out of sync with the engine. When the motor is trimmed right in/down the needle on the gauge is still 1/4 way up the dial. How do I calibrate this??

Thanks!!

 

[galamb]

Check out the diagram/instructions - that's easier than me trying to explain