Boating for Dummies 101: What’s wrong with my speedo?

by | Dec 4, 2016 | Articles

By Dom Appay – November 2016

Just had the Suzuki 90hp motor serviced and was looking forward to a good run on Moreton Bay to Green Island.

The motor was running smooth and strong, but when I looked down at the speedo it was stuck at 15km/h but the GPS read 50km/h. Huh? Broken speedo?
I hoped not!

At home, I Googled “Suzuki boat speedo not working” and came up with a blocked pitot hole to check. Sure enough the tiny hole in the front of the engine leg was blocked with mud and crap, stopping water pressure getting up the tube to the speedo head and moving the needle properly.

Using a fine drill bit, 1.8mm, inserted by hand into the pitot hole, I gently coaxed out the mud, salt and muck blocking the hole. It went in, out came a hiss of air and a dribble of dirty water.  You could use a small jeweller’s screwdriver instead of a drill bit. Easy!

All fixed in 5 mins and the speedo reading matched the GPS on the run to Horseshoe Bay!