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s/v Tiger Lily
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My blower has been broken for a while. I will probably replace it (pretty inexpensive).

Is a blower with an in-board diesel necessary? There aren't explosive gasses, so is it just for cooling the engine compartment or reducing smells?
 

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.. There aren't explosive gasses, so is it just for cooling the engine compartment or reducing smells?
Essentially, yes.

..But that's a nice feature to have. We've been considering adding one for that and to remove heat in summer by running it for 5-10 minutes after shutdown.
 

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al brazzi
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Essentially, yes.

..But that's a nice feature to have. We've been considering adding one for that and to remove heat in summer by running it for 5-10 minutes after shutdown.
Same here why wouldn't you want to move some air through. It could be argued the air gets changed while the motor is running but after that its nice to move some too. I run mine until I put the key away. I would like one in the head and while I'm at it the holding tank locker but that would be over doing it.
 

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Diesel IS explosive when vaporized and can be ignited by a tiny spark - even static electricity. Blowers are required on all commercial, diesel-powered vessels. Just a few weeks ago, I was watching Deadliest Catch on TV and they had a serious problem involving diesel vapors in the engine room. A crack had developed in the fuel line downstream of the high pressure injector pump, and the entire engine room filled with explosive diesel vapors. Fortunately, the explosive gas alarm went off and they were able to fix the problem, but in less than a minute, the vapors were so dense, that the engineer had to wear a gas mask to enter the engine room. He was scared to death that he would not be able to evacuate the fumes fast enough with the standard blowers, and had another crew member bring in a large fan to ventilate the compartment to make it safe enough to do the repairs.

In addition to the diesel fume problem, with the engine stopped for repairs, the ship began drifting sideways in 25-foot waves in the Bering Sea, which in itself is extremely dangerous, as the crab boats are often top heavy with layers of ice that forms on the steel hull and must be removed with large, rubber, sledge hammers and shoveled overboard.

The other gasses that need to be vented are battery charging gasses that are heavier than air and frequently end up in the bilge or engine compartment. They are high explosive and very easily ignited by the tiniest of sparks, such as the closing of a relay.

Install that blower in and you will be much safer,

Gary :cool:
 

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Diesel IS explosive when vaporized and can be ignited by a tiny spark - even static electricity.....

...The other gasses that need to be vented are battery charging gasses that are....very easily ignited by the tiniest of sparks, such as the closing of a relay.

Install that blower in and you will be much safer,

Gary

Yes, all of the above is true. And the type of gas that is released by flooded lead acid automotive type batteries is hydrogen. Remember the Hindenburg?
 

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Better late than never
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Another aspect to consider is helping get the heat out of the engine compartment. Cooler air is better for combustion not a huge difference but every little bit helps.
 
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Gas and diesel fuel are not very flammable in their liquid form but the fumes are. During my preteen pyro days I used to like to put a small amount of gas in a coffee can in the backyard and toss a match at it from a distance to see what it would do.

I was surprised how often the match fell directly into the liquid gas and was snuffed out without igniting the gas. But if the match bounced off the rim of the can, causing it to go in a little more slowly, it had time to ignite the fumes.

That is what carburetors did and is now what fuel injectors do, is turn the gas into a mist.
 

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Farr 11.6 (Farr 38)
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I agree with most of the above, but would add that a blower is required if you have a propane stove. At least the last time that I looked, ABYC required a bilge blower whenever there are heavier than air explosive fumes or gas on board. That would include propane.

Jeff
 

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The outlet for the blower on my boat is at the top of the transom. Nice place to warm your hands on a cold Salish Sea day.
 
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Hey,

I have owned three boats with inboard diesel engines (1986 Newport 28 w Universal, 1985 O'day 35 w Universal, 2002 C&C w Volvo / Penta). Not one came with a blower. The Newport had an alcohol stove, the O'day and C&C used propane for stove / oven. Both had solenoids for the propane, the C&C has a solenoid and a sniffer.

Barry
 

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My boat was fitted with a blower but the 3" hose run was so long and convoluted that essentially no air moved. Add in the fact that there were no other ingress routes for combustion air and the engine was starving for air at higher throttle settings. I ripped it all out and haven't had a moment of regret but this is in the PNW with <50F water year-round and a nice cool engine compartment no matter what.
 

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al brazzi
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My boat was fitted with a blower but the 3" hose run was so long and convoluted that essentially no air moved. Add in the fact that there were no other ingress routes for combustion air and the engine was starving for air at higher throttle settings. I ripped it all out and haven't had a moment of regret but this is in the PNW with <50F water year-round and a nice cool engine compartment no matter what.
You could argue the need for two blowers here one in and one out. The one pushing out a higher CFM.
 

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al brazzi
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Hey,

I have owned three boats with inboard diesel engines (1986 Newport 28 w Universal, 1985 O'day 35 w Universal, 2002 C&C w Volvo / Penta). Not one came with a blower. The Newport had an alcohol stove, the O'day and C&C used propane for stove / oven. Both had solenoids for the propane, the C&C has a solenoid and a sniffer.

Barry
Doesn't make it right or to code.
 

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Once known as Hartley18
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I'm not at all sure serious ventilation is required on a Diesel-driven sailboat for the engine compartment alone.

FWIW, I've got a Nicro solar vent installed in the aft access hatch that does a pretty good job of keeping the smells down and proving general engine-room ventilation without affecting intake air supply like a full-on blower might. It doesn't require any additional wiring and controls either.
 

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"And the type of gas that is released by flooded lead acid automotive type batteries is hydrogen."
Forget about hydrogen. Put seawater into flooded lead acid batteries, and you get chlorine gas coming out. It can eat your lungs out fast enough to make medical aid an impossibility.
 

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Once known as Hartley18
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"And the type of gas that is released by flooded lead acid automotive type batteries is hydrogen."
Forget about hydrogen. Put seawater into flooded lead acid batteries, and you get chlorine gas coming out. It can eat your lungs out fast enough to make medical aid an impossibility.
Does anyone actually use flooded lead acid batteries on boats any more?? IIRC, they haven't been marketed over here in years..
 

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Yes, all of the above is true. And the type of gas that is released by flooded lead acid automotive type batteries is hydrogen. Remember the Hindenburg?
Well not quite all true. Hydrogen is lighter than air. It's why the Hindenburg flew.
 

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"Does anyone actually use flooded lead acid batteries on boats any more?? "
Still the recreational drug of choice. Still the leading type of battery for automotive and marine use, and pretty much ALL the heavy duty "traction" batteries (aka fork lift or golf cart batteries) like the Trojans.
Last time I checked, flat plate AGM batteries were about 30% more costly than conventional wet lead and much harder to find in store inventory. And, frankly, offering no advantages at all to the typical user (with a proper charging system) except for so politely keeping the electrolyte contained.
Gel batteries being even more expensive and much easier to damage and found mainly on unicorn ranches.
Carbon foam and a few other exotics hard find in actual use even there, again because of costs.

So yes. Wet lead? Plain flooded batteries? Probably in 90% of all US pleasure craft.
 

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Once known as Hartley18
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So yes. Wet lead? Plain flooded batteries? Probably in 90% of all US pleasure craft.
Over here, sealed lead-acid (SLA) is about as close as you'll get and not all that expensive (I paid $195 for a US-made Deka not that long ago). Used on cars and boats, doesn't need top-ups and won't spill even inverted.

Whatever floats your boat..
 
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