TOPIC: trim gauge not working

Hi, I have a 1988 mercury 100hp, my trim gauge is pegged at full up, any suggestions? Is there a trim position switch that may be bad and if so does anyone know where it is located on this motor?

Thanks
Mike

Hi Mike,
The trim position sender is mounted to the starboard underside of the Merc 100 swivel bracket (this is the large cast aluminum part that the motor turns left and right on, and tilts up and down on - the serial number plate is on the outside as well). The outboard will need to be tilted up some, preferably, fully tilted to service. In another thread in this heading, a picture of a Mercury sender fairly similar to the one your motor uses is shown, except yours will have a rib (like a slotted screwdriver's blade) which mates to a female slot (like a slotted screw head) in a stainless steel pin. The rotation of this rib is what changes the resistance the gauge sees, and therefore moves the gauge's needle position.

Regards,
Joe
www.fergusonpoolemarine.com