posted 03-10-2002 07:07 PM ET (US)
They worked great when they worked. OMC came out with this idea in 1982 and when I saw it I thought "That's such a sensible idea. Why hasn't somebody thought of this sooner?" It's clean looking and eliminates the need for an unsightly hose and pitot tube running down your transom. No extra screws to drill too.The problem comes when the gearcase hits any kind of debris. The pickup gets clogged. Unlike a separate pitot tube which kicks up when it strikes something, the gearcase just slams into whatever little stuff is in the water. Yes, if your hit a big piece of driftwood, the motor will kick up too, but by then it's too late for the speedometer pickup in the gearcase.
In the case of my 1982 Johnson 90 hp on my first Montauk, the gearcase pitot got clogged up the very first time it struck something. No amount of picking and blowing ever cleared it out. I simply installed a separate Teleflex pitot as I had always done before and left it at that. In the case of the OMC motors, the speedometer hose hooked up at the top of the gearcase on a plastic barb. This plastic part was very easily broken, which in fact happened to mine eventually.
I didn't know the Yamahas still used this idea. I know in the case of the OMC motors, they abandoned the gearcase pitot before the end of the 1980's. I suspect Yamaha has a more robust system and, hopefully, a way to clear a clogged pickup. Like I said, when it works, it works great. Probably more accurate than a transom mounted pitot because it’s running in cleaner water and because of its added depth will stay in the water too.