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Any boating freaks in here ? .. need advice on bilge blower

Discussion in 'The Pub' started by VCM, Nov 15, 2008.

  1. Just getting my 'other' toy ready for this summer. Skicraft hunta 4.5m skiboat with 'modified' Holden 5.0L inboard.
    Seems my insurance company is insisting I install a blige blower.
    My questions are:
    (1) Do I install it in the bottom of the bilge? ( concerned about the possiblilty of water affecting it )
    (2) Do I setup the exhaust hose to run into an outlet outside the boat similar to a bilge pump?
    (3) Do I wire it direct to Battery power or Ignition? ( I'm guessing Ignition )

    Thanks in Advance ;-)

  2. Do you mean an engine blower?

    Ours used to vent into the cockpit and was wired to the ignition.

    Diesel engine, of course, 50ft yacht.

    In your case, I'd be trying to vent to the transom (as long as the hull design allows), coz you're trying to get rid of petrol fumes. Does your bilge have a sump? On our boat, we only ever had water collect in the sump, so as long as you mount the blower above the sump, water should not be a problem.

    But I guess there will be a few stink-boat owners on here who can answer your question definitively.
  3. Now see... these sorts of problems are why my boat has an outboard :LOL:

    Ummm no idea what to the answer to your question is BTW :?
  4. Ok its been awhile since playing with anything Nautical but i'll try to shed some light as I remember.

    Bilge Blower, to minimize the risk of explosion due to petrol / gas fumes building up in the engine bay, and ignited via a spark from the starter motor or wiring.

    There a sealed spark proof unit wired directly to the battery via the isolation switch and dedicated switch on the dash console .... NOT THROUGH THE IGN the purpose is to vent any fumes for a minimum five mins before attempting start up. The wiring must be 'spark proof' or . mine spec'd :) so there is NO risk of any spark ..... spark = BOOM
    The term 'bilge blower' is a furfie, there are exhaust fans and suck any gases outside to atmosphere , depending on the size and configuration more than one 'blower' may be needed.

    I'd need to see your boat to work out the positioning of the pickup hose,
    But they haven't got enough power suck up water :) so as low as you think [ educated guess ] its your boat and you know how much / if any water gets in. :)

    When I was right into this stuff, the 1st person on board would ,
    A: Check the bilge for water ......... has the auto pump been doing its job ? :LOL:
    B: At the same time flick the isolation switch and turn on the 'blower'

    Then the blower was active for a least 10 mins while we stocked the boat :) [ we always refueled on return from a trip ]

    A final check for fumes, while checking engine oils with the good old mark one nose detector :LOL: was done before the key even hit the Ign :wink:

    Hope this helps :)
  5. Thanks for the replies Guys :)
    I'll try to postion it away from the bottom so it wont get submerged in the event the water level creeps up.

    Bob, I have a few pics, most were at the time of rebuilding 2 years ago. Hope they show enough & would appreciate any tips on the postioning of the unit.

    Mid mount, engine compartment, fuel tank behind rear seat.
    Engine Postion:

    Engine Cover:

    Rear Section with Rear Seats, Fuel tank, Battery removed:

    Bilge Pump outlet at LHR of transom. Thinking about having an outlet for the bilge blower on the opposite side?

    ( Note for Mods: It's 5 pics per post now right? .. If not .. sorry )
  6. Ok so it is a toy :p :LOL:

    Sorry couldn't help myself, ours was just a little bigger and had two V8's @ 280hp each :twisted:

    You dont want to be venting through the back of the transom on yours, a deceleration wash could make its way into places you dont want ! :wink:

    I'd be looking at what they call 'turtle vents' in your eng cowl for both looks and functionality


    I can see the need for what the Ins company is asking for, being a petrol mtr. But its going to be fiddly to set up and still be able to get the cover off easily for servicing etc .

    I haven't got any digital pics of 'Jody' she was before the digital camera revolution :LOL: but a quick online search found one of her sisters .. 35' Bertram , cruise @ 22 knt flat out at 36knt but at that speed you could see the fuel gauge dropping very fast :LOL:


    Those where the days, just out of the Navy, no kids, living in FNQ.
    arrgh she was a grand old time o plundering the wenches n drinkin, nay a care in the world ...........

  7. Told ya it's a TOY :wink:
    But it's serves its purpose, skiing etc.. and still manages 55mph on water :p
    Thanks Bob
    I'm guessing any fumes will be directed toward the back seat, but if operated before we load any passengers this shouldnt be a problem to them.
    That some 'boat' mate !
    PS: thanks for the PM, will head down to JV :)
  8. Bilge blowers are available to move air in two ways - some units feature a squirrel cage configuration, while others favor a "tunnel", or "in-line" design which utilizes a small fan. The type you choose will depend on the space available and on how you plan to mount it. Both types evacuate air very efficiently, and are available in sizes which handle 100-250 c.f.m. (cubic feet of air per minute). The size you need is determined by the volume of your engine compartment