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      I have a B40 from 2010 – the Farr designed boat. This is fitted with a D2-40 engine.

      In the engine bay there is an extraction fan that blows when the engine is turned on – well it used too – it has now stopped working. I can see that it is powered by a cable – black is positive and white is negative but there is no voltage coming out of this cable. The cable goes into the wiring harness at the rear of the engine but I cannot see where it goes to. There seems to be a black box on the port side of the engine that most cables connect to – the various engine sensors, the cockpit control panel etc. Turning the engine on from the cockpit control panel should turn on the power to the cable.

      I already have a 12 volt power source that I wired into the engine bay powered from the 301 panel so I added a connection to this to supply the fan and I have fitted an additional switch to control the extraction fan. The fan now works successfully – I just have to remember to turn it on when required.

      Does anyone have any information as to how to get the original installation working – is there a fuse or ??????


        Great question here Paul and it’s a pity that there has not been a fruitful response!

        I have the same problem. On my recent trip the in line blower in the engine bay decided to give up the ghost…. after a lot of screaming, graunching and complaining I might add.

        I have sourced and replaced the unit but there is no power to it so I am guessing that there must be a blown fuse somewhere but I just can not find it.

        So a call for help out there to all of the “clever techies” that I know that we have in the group… or maybe even to Clipper – “Where is the fuse”?



          Paul. Steve. Hi I cannot find a circuit diagram for you engine not even a schematic diagram. However, I believe that the setup for the D2-40 is very similar to my D1-30 in that the + feed for the blower is taken from the non permanent + post on your splitter via a fuse. The – is taken back to the engine block via the loom.

          If its the same the black wire is the – and a white wire is the + (on mine this wire is coded no 11). Both wires connect to the blowers wiring and they change colour at this point.
          If the blower is faulty it will have blown the fuse so checking the voltage before the fuse will be necessary. I am not sure of your level of electrical knowledge (or any one reading this) so I have attached some photos and a quick how to.

          With the engine off but the battery still connected use a multi meter set to 0-20 +/- DC volts. Check that where the white cable terminates (before the fuse on the big terminal) If there is no voltage between this terminal and the engine block (or the battery If its close enough to get to with your leads) this is the switched terminal. If you have not got a multi meter you can use a 12v bulb connected to two wires.

          Clip the wires or leads in position at the same place as above and start the engine you should now be seeing 13.8 volts or there about. Or the lamp will light. Confirming the terminal is only + when the engine is on.

          Switch off the engine and check the fuse. Replace as necessary.

          You should now have 13.8 volts at the blower when the engine is running. Check this using the same method as above but at the point the black and white wires joint the blower wires.
          All being well you can now reconnect your new blower. When running it should suck warm air out not blow cool air in. If it does the latter just swap the wires over at the point the connect to the blower.

          Any problems or if yous is different give me a shout.

          Hope this helps.



            Spot on Ant.
            The Blower on my 32 is fed from the centre post of the “Multi Battery Isolator” located in the engine bay.
            The white wire is split with a black fuse holder about 2 inches from the connection at the post end.
            It contains a simple 5A glass fuse.





              Thanks for the information about the fuse – it had blown presumably after the blower failed.
              So I disconnected the blower from the temporary connection I provided and connected it back to then centre connection of the diode splitter and it now works just when the engine is running. However I did think that with this connection it seemed somewhat noisier than when connected to my temporary connection. This centre connection is where the alternator is connected and the battery sense connection for the alternator is connected to one of the batteries, so after the splitter diode. So effectively the fan connects to the output of the alternator. I measured the voltage output from the alternator – it was 15.2 volts – but after the diode splitter the voltage was 14.4 volts so a drop across the splitter of 0.8 volts – about right for a silicon diode.
              So this high voltage being fed to the fan would explain why it is now noisier.
              Looking at the specification of the fan it is nominally rated at 13.6 volts so the alternator output voltage is rather high and this may have shortened the life of the fan. I am going to try to correct this by putting at least one diode into the fan supply to bring the voltage down. I diode rated at 6 amps should be suitable.


                After talking to Clipper it was decided that the blower was only put in to meet RCD rules particularly for warmer climates.
                To that end I fitted an inline switch to mine which now allows me to go into “stealth mode”…. certainly quietens things down when not needed, great for early marina starts!
                I dare say that the more tech minded out there could even rig this up to a thermostat to meet the best of both worlds?

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