speedometer problem on Yamaha

[ssaamm]

Ran into a very minor issue on the opener. My speedometer on my '02 90hp Yamaha 4-stroke was not reading accurately. It either read two dashes (--), or 7-8mph when I was at full throttle. I know my buddies and I have put on a few since the good old days and the prop has a ding or two, but the gps read us at 37mph. Any help would be great. The rest of the display on the dash-- rpm's, the clock, voltage-- were working fine. Thanks

[marine_man]

Do you know what kind of spedometer pickup you have? I belive the 90 HP motors had a built in spedometer in the lower unit...

What could have happened is something got stuck in there - look on the leading (forward) edge of the lower unit for a little notch / hold in that edge below where the lower unit splits from the mid section of the motor... you can use air pressure to actuate your speedometer to see where the problem is... just don't blast it with 90 psi of air... you could damamge your speedometer.

If the speedometer tube routes to a pickup mounted near your locator transducers check to see if anything got stuck in the pickup portion of it...

marine_man

[Deitz Dittrich]

If you have GPS speed, why even worry about boat speedo?. . they arent all that accurate anyways?

[ssaamm]

Cleaned out the little notch in the lower unit, and it worked like a charm. Surprisingly the gps and speedometer were identical. Thanks for the help.

[marine_man]

Glad to hear you got it figured out...

marine_man