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h2oskier
06-23-2006, 11:28 PM
I was waxing the haul and moved the speed-o pick up with my finger. When I went to the lake the next day, no speed reading. It was not until I was at almost full throttle that I started getting a reading on both speed-o's. I think they are off however.

Is there a way to calibrate baised off the tach?
(MC 209 with the MCX engine)

What gives with the pick-up anyway, is it bad to spin this by hand?

JohnnyB
06-24-2006, 09:03 AM
If I remember these pickups right, there should be no issue with bending them.....that is not what senses speed. Their is a small hole at the tip of each pickup. This allows water to come in and senses the speed.....they are pitot tubes and this is the pickup point. Often, these holes get clogged with some type of debris and will cause your speedometers to not read correctly. You can clean them out carefully with a safety pin.....used to keep one of these handy as it was funny how often I'd pick something up in the pitot tube and loose a speedometer.

As far as calibration, I typically use a GPS to set them.

TMCNo1
06-24-2006, 10:03 AM
If I remember these pickups right, there should be no issue with bending them.....that is not what senses speed. Their is a small hole at the tip of each pickup. This allows water to come in and senses the speed.....they are pitot tubes and this is the pickup point. Often, these holes get clogged with some type of debris and will cause your speedometers to not read correctly. You can clean them out carefully with a safety pin.....used to keep one of these handy as it was funny how often I'd pick something up in the pitot tube and loose a speedometer.

As far as calibration, I typically use a GPS to set them.


I think he is talking about the new electronic /thru hull speedo units with the spinning wheel vs the old pitot style that hangs off the transom.

SkiDog
06-24-2006, 10:08 AM
I think he is talking about the new electroni /thru hull speedo units with the spinning wheel vs the old pitot style that hangs off the transom.


Damn, you ARE still alive! Check your PM
(sorry for the tread jack)

TMCNo1
06-24-2006, 10:24 AM
Damn, you ARE still alive! Check your PM
(sorry for the tread jack)


And well, you, check your PM reply! Now who's alive?

vogelm1
06-24-2006, 11:24 AM
I assume you have the "paddle wheel" speed sensor on your boat....if you said you bumped it, does it still spin freely? There is a little axle going thru the paddle wheel that is designed to be removed should you need to change out the wheel...maybe that got lodged slightly.

If you did end up getting the speedos to work now, but you don't think they're accurate, a GPS unit works real nice for getting it set for open water type skiing. If you ski a course, then obviously you'd want to calibrate based on time it takes to drive thru course - that is most accurate of them all. For general "rule of thumb" my boat runs about 30 mph at 3000 rpm (2005 PS 197 with MCX).

vogelm1
06-24-2006, 11:28 AM
Also, your question about is it OK to spin them by hand...it's OK, but if you consistently trailer your boat hundreds of miles, it would be a good idea to put duct tape over the wheel, or use the 'dummy' plug that should have come with your boat to save wear and tear on the sensor.

JohnnyB
06-24-2006, 12:02 PM
I think he is talking about the new electronic /thru hull speedo units with the spinning wheel vs the old pitot style that hangs off the transom.

Yup, missed that the 1st time....just looked at his profile now.

kjohnson
06-26-2006, 10:41 AM
The easiest way to calibrate is use a GPS device. If you don't own one, borrow one. You can buy one for $100.