Speedometer not working

[Captain Lucy]

I was boating out of state and brought my boat to a dealer for a bellow change. After the repair I noticed the speedometer wasn't working. I have a 1997 Bayliner with a Mercruiser 135hp Alpha 1 engine. Could a wire have been knocked loose during the bellow repair. Where in the engine compartment would I start the seach?
Thanks,
Captain Lucy

 

[jmoorepghpa]

Re: Speedometer not working

The spedometer runs off a spedo pick up assembly mounted on the exterior bottom of the transom. It is a little "fin" that sticks down about 2" past the bottom of the hull and picks up water pressure from the forward movement of the boat and transmits that pressure via a flexible tube up to the spedo. The spedo pick up is designed to hinge backwards and up if struck by an object to prevent damage. Make sure that it is in the down position and the tubing is still atatched to it. It could have been easily bumped while they were doing your bellows job.

 

[I/O WALDO]

Re: Speedometer not working

No pitot tube on this boat! The speedo tube is connected (when not knocked off when the bellows is replaced) to the bottom half of the lower unit.Raise the drive all the way,turn the drive either st.or port and look at the center,foward part or the drive.You should see a little black hose hanging loose under the exhaust bellows.Look into the drive where the hose will reach and plug it into tho hole it belongs.

 

[Captain Lucy]

Re: Speedometer not working

Thanks WALDO. I found a little black hose with a white plastic tip disconnected. It slipped on easily.
Captain Lucy

 

[jmoorepghpa]

Re: Speedometer not working

Ahhh... you are wise in the ways of the alpha 1.

 

[monkey710]

Re: Speedometer not working

Sorry to revive an old thread, but the location of the connection: was it forward end of the unit just above the cavitation plate by the zinc anode? If not, can you dumb down the location for me? I am having speedometer troubles also and all my voltages are fine.

 

[monkey710]

Re: Speedometer not working

Well, I found the connection, but another question. How much deflection should I get when I blow into it. I see the unit move but slightly. I also blew into it from the other end and air went through (hard, but probably due to the tiny hole on the other end).

Unfortunately, I cannot test it until I get into the water, so I want to trouble shoot everything I can before then.

Thanks

 

[monkey710]

Re: Speedometer not working

Anyone?

 

[Silvertip]

Re: Speedometer not working

If the needle moves at all, it's working.

 

[jammer]

Re: Speedometer not working

Anyone?

What they are saying..is connect the tube you'll see. It's fine. But the ultimate test is really on the water.

 

[Big Keepers]

Re: Speedometer not working

Get yourself a nice GPS or a sonar/GPS combo and use that speedometer. The most accurate thing on the water. Even a handheld goes to the tenth of a MPH.

 

[wcsparky05]

Re: Speedometer not working

or if you want to test it at home someone on here told me to push air through using a compressor. you got the needle to move with your mouth? that's impressive!

 

[monkey710]

Re: Speedometer not working

Thanks...I got about 5-10 mph while blowing...hopefully I cleared up whatever was clogging it.

I will test on Saturday...