speedo operation

[puddle jumper]

Looking at my boat and it apears to have a vacume controled speedo.Is this correct. Also at what angle is the best angle to have it at to get the best reading, 90degs to the bottom ??

 

[tashasdaddy]

Re: speedo operation

it's a pressure speedo, water put pressure on a small hole it the pickup, thus pressurizing the line, and moving the needle.i try to keep mine with the trailing edge so that it is in line with the stearn.

 

[Chris1956]

Re: speedo operation

Puddle, The speedo is a water pressure guage, fo rall practical purposes. Mount the Pitot (pickup) so that it will be in the water at all times. I had to move the Pitot on my speedboat closer to the motor, so it would be in the water at high speed. No real magic to the angle or height, just so projects below the bottom of the boat at all speeds.

PS these are known to be inaccurate. You might check your speed with a GPS to calibrate the speedo in your mind.

PPS - if you make the pitot hole larger, your speedo will reader a higher speed. Do you think the boat will really go faster?

 

[puddle jumper]

Re: speedo operation

thanks for the info. that makes more sence.