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Engine Room Air Flap Solenoids

Discussion in 'Engines' started by DOCKMASTER, Apr 13, 2020.

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  1. Pascal

    Pascal Senior Member

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    Manual pull cables may work on smaller boats but not when the helm is a longer distance from the ER where cables run won’t work
  2. jhall767

    jhall767 Senior Member

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    This is the first step. I've fixed more than a couple shutdown relays by just disassembly, cleaning and reassembly. Since it doesn't work now you've got nothing to lose but a little bit of effort.
  3. DOCKMASTER

    DOCKMASTER Senior Member

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    Your spot on Pascal. Besides, it interfaces with the Fireboy system to close the doors if the system gets set off so the suppression agent is contained in the engine room.

    I'm going to find replacements of one sort or another. I'm not keen on trying to clean or fix these. They are pretty far gone and even if we could make them work I won't have confidence in them.
  4. rtrafford

    rtrafford Senior Member

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  5. DOCKMASTER

    DOCKMASTER Senior Member

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  6. DOCKMASTER

    DOCKMASTER Senior Member

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    So finally spoke to someone at Trombetta with good technical knowledge. They suggested a solution using a more modern, readily available solenoid and a module. I would need the module as the newer solenoids require more amps. The module is very basic, you give it a power source and a signal then connect it to the solenoid. Each solenoid requires 40 amps.

    According to Trombetta, they make the Detriot Diesel solenoids and he said they only have 4 #'s pull force because they are only designed to pull the fuel pump lever. He doubts they will have enough force to drop my doors.

    So I'm likely going to use the newer solenoids and modules or we are exploring an option with a compressed air actuator, a small dedicated air bottle and a simple solenoid valve.

    What a PITA!
  7. d_meister

    d_meister Senior Member

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    One would think that the system worked at some point in the past. Are there any surveys in your files indicating there was a previous problem?
    Maybe you could increase pull force by adding a pivot and lever, or, add a counterbalance to the flaps?
  8. DOCKMASTER

    DOCKMASTER Senior Member

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    I'm sure it worked until recently. No, I'm not going to use those old solenoids. I would never trust them and don't like to cut corners on anything, especially fire/safety related stuff. We're going with the alternate solenoids and modules Trombetta has suggested.
  9. Capt J

    Capt J Senior Member

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    I think that's a good idea. I'd rather have that then the air compressor and an air system (another system to maintain).
  10. wdrzal

    wdrzal Senior Member

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    I think that system was designed in reverse of how it should work. I think the solenoids should open the intake when anything in the engine room is powered on. A solenoid would use very little power to hold a spring loaded auto close damper open. The default position should be closed. Many different items could instruct them to open ,Gen sets, engine starts, or just the engine room temperature getting above a set point. Then again ,a fire and all bets are off. They lose power either per instruction/design of fire suppressant system & auto close. Fire melts wires, shorts or breaker kick ,still auto close.
  11. rtrafford

    rtrafford Senior Member

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    Good thought process. I use the forward flaps for forced air injection into the ER, and the remaining flaps for input/exhaust as needed by air pressure. Whenever any engine system starts the forced air system is energized. That circuit opens all of the flaps, and shut down closes the flaps. We can leave the forced air injection running after shutdown via an override, and that allows the flaps to remain open, heat exhausted. When it comes time to work in the ER we crank up the chilled water air handler dedicated to the space.

    The flap system is controlled by 1) a breaker for constant power that energizes a contactor triggering the power. 2) override switch that alternatively energizes the same contactor.