2007 sundeck 240 speedo problem

Danny Lindstrom

New Member
May 13, 2019
4
Boat Info
240 Sundeck 2007
Engines
6.2 MPI With Bravo Three Drive
My Speedo has not worked since I purchased the boat six months ago. All other gauges work, the Pitot tube is clear as I have blown compressed air through it. Electrical connections are tight.
How do I determine if it is the gauge or the transducer that is bad?
 
When you blew air through... from where did you blow air through - and where to? All the way to the SC pitot sensor from the drive pitot hole?
 
+1

The factory transducer doesn’t provide speed info.

Look near the rear of the port side valve cover. The pitot tube comes up from the drive and is attached to a pressure sensor. It has a 3 wire connector on it.
Smartcraft uses this pressure sensor to drive the Speedo on the dash.

Blowing air into that tube should produce some bubbles from the area of the outdrive.

The tube could also not be connected properly to the outdrive. It has to be reattached to the lower unit as the drive is reinstalled.
 
Last edited:
on my 210 it had mud in the foot hole, i pulled the line from behind the speedometer and blew air with a air tank, it now works. i took a needle and loosened the dirt first
 
When you blew air through... from where did you blow air through - and where to? All the way to the SC pitot sensor from the drive pitot hole?

I disconnected the pressure sensor on the engine port side and blew compressed air from the engine side and had a helper watch for water and air discharging from the outdrive. No air leaking was detected in other places.
 
+1

The factory transducer doesn’t provide speed info.

Look near the rear of the port side valve cover. The pitot tube comes up from the drive and is attached to a pressure sensor. It has a 2 wire connector on it.
Smartcraft uses this pressure sensor to drive the Speedo on the dash.

Blowing air into that tube should produce some bubbles from the area of the outdrive.

The tube could also not be connected properly to the outdrive. It has to be reattached to the lower unit as the drive is reinstalled.
Might you have a pic of this area? I can't find anything on my engine where my speedo hose would come into a barb on my engine. Do you know where on the harness it plugs into? I've repowered my 05 SR Sundeck 240 from a 5L to a 350 MAG and I imagine nothing was done to remedy this on the new engine... so, I have the hose hooked up where it should be at the bravo 3 end, coming through the transom, into the engine compartment. My issue is finding where that hose goes in the engine compartment, specifically, what part of the wiring harness should a barb plug into ... I imagine I need kit 881879A22, I just have to know where it plugs in to on the harness so it hits the smart craft gauges ! (all gauges have always been smart craft , so no converting from anything else.
 
I disconnected the pressure sensor on the engine port side and blew compressed air from the engine side and had a helper watch for water and air discharging from the outdrive. No air leaking was detected in other places.
Try one more thing... have your helper plug the pitot hole (duct tape, for example) on the drive and put some air pressure (under 10 is plenty) into the disconnected sensor/hose. Same as you did already. But this will make sure that there isn't another leak somewhere that doesn't always show up.

If all is clear... MOST likely is the sensor is shot. It's much less likely for something else to be the issue.
 
Might you have a pic of this area? I can't find anything on my engine where my speedo hose would come into a barb on my engine. Do you know where on the harness it plugs into? I've repowered my 05 SR Sundeck 240 from a 5L to a 350 MAG and I imagine nothing was done to remedy this on the new engine... so, I have the hose hooked up where it should be at the bravo 3 end, coming through the transom, into the engine compartment. My issue is finding where that hose goes in the engine compartment, specifically, what part of the wiring harness should a barb plug into ... I imagine I need kit 881879A22, I just have to know where it plugs in to on the harness so it hits the smart craft gauges ! (all gauges have always been smart craft , so no converting from anything else.
I’ll get a picture for you in a bit when we get back to the dock.
 
Here are some pics of the Smartcraft pitot connection.

It is located on the port side of the motor just aft of the ECM.


0211EA57-83D8-400A-AE99-8918E6361B30.jpeg 8E952CFB-8E51-4A0E-AD3A-14623A880EB0.jpeg 796AD0E9-2119-4F47-A067-73A952AEA757.jpeg 8C50AA11-9878-411A-89E3-72C8B350A700.jpeg
Might you have a pic of this area? I can't find anything on my engine where my speedo hose would come into a barb on my engine. Do you know where on the harness it plugs into? I've repowered my 05 SR Sundeck 240 from a 5L to a 350 MAG and I imagine nothing was done to remedy this on the new engine... so, I have the hose hooked up where it should be at the bravo 3 end, coming through the transom, into the engine compartment. My issue is finding where that hose goes in the engine compartment, specifically, what part of the wiring harness should a barb plug into ... I imagine I need kit 881879A22, I just have to know where it plugs in to on the harness so it hits the smart craft gauges ! (all gauges have always been smart craft , so no converting from anything else.
 
thanks so much !! this really helps. i will look and hopefully my harness has this connector somewhere in there !!
 
Try one more thing... have your helper plug the pitot hole (duct tape, for example) on the drive and put some air pressure (under 10 is plenty) into the disconnected sensor/hose. Same as you did already. But this will make sure that there isn't another leak somewhere that doesn't always show up.

If all is clear... MOST likely is the sensor is shot. It's much less likely for something else to be the issue.

One more question before I purchase a pressure sensor. My speedo has two three wire plugs one is connected to the network the other three wire end has no plug. Its just open. Definitely not left this way by the factory. Some older network protocols require a terminator at the end of line. Is a terminator plug required?
 
One more question before I purchase a pressure sensor. My speedo has two three wire plugs one is connected to the network the other three wire end has no plug. Its just open. Definitely not left this way by the factory. Some older network protocols require a terminator at the end of line. Is a terminator plug required?
Do what I did and get yourself a GPS speedo.... no more water, sensors or wiring to the harness. $55 on eBay and you grab some power from the ignition. I did it to mine and it works great.... so easy AND cheaper !
 
One more question before I purchase a pressure sensor. My speedo has two three wire plugs one is connected to the network the other three wire end has no plug. Its just open. Definitely not left this way by the factory. Some older network protocols require a terminator at the end of line. Is a terminator plug required?
The Speedo is on the left end of the gauges. That is just a pig tail for the backlighting and communication line for any gauge that would be placed further to the left on the dash. I have the same thing in my 2007 240. The harness isn’t connected to anything.
 

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