View Full Version : Speedometer Help

05-04-2005, 04:41 PM
We are the new owners of a 1997 Prostar 205, our first inboard. Had the boat out for the first time last weekend since the test drive late last fall and noticed that the right speedometer needle was bouncing around and when steady, it showed 2-3 mph difference from my left speedometer. How do you calibrate the speedometers? Is the needle bouncing due to a dirty peto tube?

I sure would appreciate any help in this area. And I do love this boat!!! What a change from the SeaRay! :D :D

east tx skier
05-04-2005, 04:45 PM
There's a little knob on your guage with which you can adjust the speedo. Without a GPS, perfect pass, or a slalom course to test speed, assuming you have a 1:1 transmission, 3,000 rpm roughly equals 30 mph with two people in the boat.

As for the bounce, it could easily be clogged, but often, they tend to hang or not work at all. Maybe it's a partial clog. Just go back there and work a needle around in the pitot tube. If a bunch of water suddenly comes out, you've found your problem most likely.

Congrats on the new boat. It's a great one.

Was your old boat a Sea Ray or a Ski Ray. One of my wife's uncles has the Ski Ray. Cool boat, but a huge rooster tail.

05-04-2005, 04:58 PM
I think this may be your problem....I had similar issues. the ballast tube in mine must have gotten water in it then a winter came along and the ice in the tube put pin holes in the tube. So my needle was acting weird. I silver soldered the tube back together and it was all good. Check the brass ballast tube!

05-05-2005, 08:08 PM
Thanks for the help I will check everything mentioned. Our previous boat was a Sea Ray 185 Bow Rider. To Britt.....we also used a High Five prop on the Sea Ray. What a great prop. Changed the total performance of the boat.

05-05-2005, 08:19 PM
I keep a paperclip on my boat's keychain for unclogging. Works just fine. I have also seen little squiggly looking gadgets that attach to the keychain for the same purpose.
Welcome to the world of inboards. Nothing else like the performance of a fine inboard direct drive machine.