Speedometer Question

[lowmover]

I have a 1996 Bayliner Capri SS with a 5.7 L Mercruiser. The speedometer has never worked since I bought it 3 years ago but I have decided to fix it now. So far I have:

Found the hose that connects to the back of the gage and traced it back to the engine compartment. I cut the hose and applied air pressure to the gage side and the gage went up and down. Then I applied pressure to the lower unit side and no air would pass through the hose at all, is this normal? I found where it connects on the outside of the boat and unplugged it I applied air pressure on this end and it blew out of the hose I had cut. I have also found the 2 holes on each side of the lower unit where the water creates the pressure, I believe. When I blow air in the holes the air seems to come out around the hose plug where my hose was hooked up, is that normal. When I hooked everything back up it still will not blow out of the hose that I cut in the engine compartment down and out of the lower unit. I will splice the hoses back together to test in the water but I haven't put it in the water yet to test it but I don't think it will work as is. Any comments on what I should check for?

 

[Bondo]

Re: Speedometer Question

I have also found the 2 holes on each side of the lower unit where the water creates the pressure, I believe.

Ayuh,... Welcome Aboard,... There's a Single pitot hole, Dead Center of the drive, down low,...

I'm guessin' yer's is plugged up...

 

[UncleWillie]

Re: Speedometer Question

Ayuh,... Welcome Aboard,... There's a Single pitot hole, Dead Center of the drive, down low,...

I'm guessin' yer's is plugged up...

Look here.

 

[dockwrecker]

Re: Speedometer Question

The easy replacement is to grab the hose at the drive and attach a new one to it and pull the new hose back to the gauge. And after you've blown half an afternoon doing it, if it works it will still probably be wrong but you'll have the pleasure of watching the speedo needle move aimlessly about. Learn to ignore it and use the GPS on your phone or learn to use your tach (much better anyhow) as to how fast your boat is really going or where it's "sweet spot" is.

 

[jdlough]

Re: Speedometer Question

after you've blown half an afternoon doing it, if it works it will still probably be wrong but you'll have the pleasure of watching the speedo needle move aimlessly about. /QUOTE]

Yep, take any money you were planning on using fixing this, and use it on a new Combo FishFinder/GPS.

 

[04fxdwgi]

Re: Speedometer Question

My speedo didn't work either, when I got my boat. Tried:
1. Put new "O" ring on connection to drive..... Didn't fix it.
2. Cleaned out pick up in lower unit..... Didn't fix it.
3. Removed hose from speedo and blew air through..... Didn't fix it.
4. Applied air pressure to hose outside boat and speedo moved slightly. Figured, bad speedo and replaced. Didn't fix it.
5. Found hose inside boat crimped by by a tight cable tie and pinched. Replaced the hose..... That fixed it....

 

[TimBobCom]

Re: Speedometer Question

...you'll have the pleasure of watching the speedo needle move aimlessly about.

The only time I look at my speedometer is to see how far off it is from my GPS. Although I do try to keep debris out of the pitot intake on the drive just to keep it working and it's easier to clean out a little debris than a major clog.

 

[spoilsofwar]

Re: Speedometer Question

The speedo on my Stingray is fairly accurate, usually within 3mph of my GPS or so, sometimes more though. Sometimes its way off, like when it just sits at zero regardless of how fast I'm moving (the pitot pickup on my drive must be covered by weeds or whatever).

I can agree that if it ever stopped working its not really worth any money to fix it, but, maybe like the OP, it would bother me to just watch it sitting at zero forever.

 

[UncleWillie]

Re: Speedometer Question

...I cut the hose and applied air pressure ... I will splice the hoses back together to test in the water but I haven't put it in the water yet to test it ...

Be sure to splice it back together before putting it back in the water.
If it is working at all, the open hose will squirt water into the boat when you are moving.
Bilge pump working?


I am surprised by the number of people that suggest NOT to repair systems that are not working.

The speedometer is just one example of those systems that many say, "I don't use it, so I don't need it working."
Many of these same folks keep wondering why the bilge always has 3 gallons of water in it when the lake was calm and there was no water splashed about.
If they had repaired their useless Speedo, they would have found the broken pitot hose that was flooding the boat.

Many other "useless" items on the boat can have serious unseen consequences once "murphy "arrives.
If it is on the boat it should be operational.
Fix it, or properly remove it!

 

[TilliamWe]

Re: Speedometer Question

Look here.

View attachment 149520

And this is probably how it will actually look:

plugged up.