Ok Guys after all the ETec sprawl .. I want to focus on my Merc powered
boat again

I have an inboard motor and the fuel tank is below the floor. The motor
sits under a doghouse and is open to the tank. There is no floor
covering the tank under the doghouse.

I want to install some noise insulation and want to encapsule the
doghouse/motor in absorbant materials which will mean to install a
floor between motor and tank.

My question is where I need to have the blower blowing to.

I understand i will only have it blow into the motor compartment but
NOT into the tank/bilge.

Am I correct? ... dont want to blow up the quietly running boat

Take in mind that with an Optomax powerhead there should be very little
fumes there anyways as all the gas ends up directly in the cylinder and
does not have a chance to come out of carbs.

Matt

Perhaps I don't understand the issue. A bilge blower is used to evacuate
from the bilge area gas vapors (which are heavier than air and settle in the
bilge). This is to prevent an explosion should a spark be present to ignite
the fumes. "The question is, where do I have the blower blowing to?"
Typically there is an inlet grill or clam shell to let in fresh air and a
grill or clamshell where the output of the blower attaches to take the fumes
outside the boat.

Don Dando





wrote in message
ups.com...
Ok Guys after all the ETec sprawl .. I want to focus on my Merc powered
boat again

I have an inboard motor and the fuel tank is below the floor. The motor
sits under a doghouse and is open to the tank. There is no floor
covering the tank under the doghouse.

I want to install some noise insulation and want to encapsule the
doghouse/motor in absorbant materials which will mean to install a
floor between motor and tank.

My question is where I need to have the blower blowing to.

I understand i will only have it blow into the motor compartment but
NOT into the tank/bilge.

Am I correct? ... dont want to blow up the quietly running boat

Take in mind that with an Optomax powerhead there should be very little
fumes there anyways as all the gas ends up directly in the cylinder and
does not have a chance to come out of carbs.

Matt

Around 2/22/2006 8:41 PM, wrote:

My question is where I need to have the blower blowing to.

Blowing *to*? Except for a few oddballs (boats that couldn't get enough
air into the engine compartment at speed), every blower I've seen blows
TO the same place: Outside the boat.

Exchange the word "pump" for "blow" and you'll see what I mean.

I understand i will only have it blow into the motor compartment but
NOT into the tank/bilge.

A bilge blower is used to evacuate explosive fumes where the potential
for a spark exists. Usually that means the engine compartment, but,
depending on how paranoid you want to be and your budget, why not do
both compartments?


--
~/Garth - 1966 Glastron V-142 Skiflite: "Blue-Boat"
"There is nothing - absolutely nothing - half so much worth doing
as simply messing about in boats." -- Kenneth Grahame
~~ Ventis secundis, tene cursum ~~

Garth Almgren wrote:
Around 2/22/2006 8:41 PM, wrote:

My question is where I need to have the blower blowing to.

Blowing *to*? Except for a few oddballs (boats that couldn't get enough
air into the engine compartment at speed), every blower I've seen blows
TO the same place: Outside the boat.

Actually the blower blows fresh air in and displaces gas fumes through
a vent. That is as not to suck gas fumes over the blower motor




Exchange the word "pump" for "blow" and you'll see what I mean.

I understand i will only have it blow into the motor compartment but
NOT into the tank/bilge.

A bilge blower is used to evacuate explosive fumes where the potential
for a spark exists. Usually that means the engine compartment, but,
depending on how paranoid you want to be and your budget, why not do
both compartments?

Thought about it too ... but there must be a reasonable limit .. I
assume it makes sense to get rid of the gas fumes from where sparks are
(motor compartment)

Matt

wrote in message
ups.com...

Garth Almgren wrote:
Around 2/22/2006 8:41 PM, wrote:

My question is where I need to have the blower blowing to.

Blowing *to*? Except for a few oddballs (boats that couldn't get enough
air into the engine compartment at speed), every blower I've seen blows
TO the same place: Outside the boat.

Actually the blower blows fresh air in and displaces gas fumes through
a vent. That is as not to suck gas fumes over the blower motor




Exchange the word "pump" for "blow" and you'll see what I mean.

I understand i will only have it blow into the motor compartment but
NOT into the tank/bilge.

A bilge blower is used to evacuate explosive fumes where the potential
for a spark exists. Usually that means the engine compartment, but,
depending on how paranoid you want to be and your budget, why not do
both compartments?

Thought about it too ... but there must be a reasonable limit .. I
assume it makes sense to get rid of the gas fumes from where sparks are
(motor compartment)

Matt

The motor is a sealed unit. And is designed to suck the fumes out. There
is a hose to the bottom of the bilge from the blower. And then a open vent
to the bilge. The open vent always seems to have a hose to the bilge also.