My speedometer does not work

[Madracer]

The speedometer on my old boat does not work. I do not understand how a speedometer works on a boat. So I guess what I am asking is how do these work and what do I need to do to put a new one in if thats the problem.

Any help is greatly appreciated.

 

[JB]

Re: My speedometer does not work

Many of those old boat speedos ran on water pressure from a pitot tube mounted on the outboard or on the transom.

Look on the back of the speedo. Is there a plastic tube there? Take it off and blow through it. If it is clogged that might clear it. If it is not clogged then the speedo instrument is probably broke. It can be replaced.

 

[Madracer]

Re: My speedometer does not work

kinda funny there is not a tube at all, looks like it is supposed to have one but doesnt. Can it be replaced and does it have to be some kind of special tube? do you have to purchase this tube from somewhere special?

 

[JB]

Re: My speedometer does not work

I think plain old plastic tubing would work, racer. Check your lower end/transom for where the other end goes.

 

[mthieme]

Re: My speedometer does not work

Rubber vacuum tubing from the auto parts store will work and is cheap.

 

[ebry710]

Re: My speedometer does not work

I prefer clear tubing. You can see whats in it.

 

[Tacklewasher]

Re: My speedometer does not work

If the tube is gone, you may also need the actual pitot thingy.

Is there something like this on the back of your boat?

http://www.iboats.com/Faria_Pitot_Tube/dm/*******.197550786--**********.133636384--view_id.38659

These speedos are terrible and lots of people have just removed them and picked up a gps instead. Even the cheapest of gps is far more accurate than one of these speedos.

 

[Silvertip]

Re: My speedometer does not work

You need a pitot (pickup) like that shown below mounted on the transom or if the motor has one built-into the lower unit, connect the tube to that. As the boat goes through the water, water pressure compresses the air in the tube which moves the pointer in the speedometer.

The pitot is the white plastic thing in the lower left corner of the picture. You don't see a tube connected to it because the tube was moved to the pickup on the motor.