Quiet but reliable bilge blower

[BoatPoor]

Any suggestions on a good but quiet inline 3" bilge blower?
The current unit is an old metal bodied Jabco that is under the floor of the aft cabin, so noise is a major concern.

 

[markpierce]

Get a larger blower. Would the blower be needed for a continuous time? Why?

My blower is about 8 inches in diameter. The photo displays the grated inflow port behind the pilothouse door. The exhaust port is on the opposite side. I primarily use the blower when the engine is hot while I'm in the engine compartment. Blower sound is mild (it's just a fan). Don't have info on the blower.

 

[BoatPoor]

Hey markpierce, it and a few fans will be running fairly continuous for the first week or so after we actually close the deal on the boat. It has been sitting for over two years and the carbs are seeping fuel causing the whole boat to reek of gasoline.

The current blower is making noise and is in a fairly tight spot so it needs to be fairly compact.

For right now, we're actually going to rent it out as an Airbnb when we aren't using it so I need to get all of the fumes vented thoroughly and the smell out of the bilge and cabin.
After I rebuild the carbs and get the seepage cleaned up it should be fine but I've been reading reviews about how a lot of these new blowers are pushing 80-85 db.

 

[Gdavid]

Hey markpierce, it and a few fans will be running fairly continuous for the first week or so after we actually close the deal on the boat. It has been sitting for over two years and the carbs are seeping fuel causing the whole boat to reek of gasoline.

The current blower is making noise and is in a fairly tight spot so it needs to be fairly compact.

For right now, we're actually going to rent it out as an Airbnb when we aren't using it so I need to get all of the fumes vented thoroughly and the smell out of the bilge and cabin.
After I rebuild the carbs and get the seepage cleaned up it should be fine but I've been reading reviews about how a lot of these new blowers are pushing 80-85 db.

That sounds truly terrifying, I can't imagine a marina or insurance company comfortable with a boat with gasoline fumes and oblivious guests paying to stay aboard without oversight. I understand there are economic factors but I would pause on everything until you are certain the gas leaks are secured. Are you certain the tanks are sound and not contributing to this problem.

 

[BoatPoor]

That sounds truly terrifying, I can't imagine a marina or insurance company comfortable with a boat with gasoline fumes and oblivious guests paying to stay aboard without oversight. I understand there are economic factors but I would pause on everything until you are certain the gas leaks are secured. Are you certain the tanks are sound and not contributing to this problem.

Nothing is being done with the boat until I rebuild the carbs and evacuate the fumes. They're typical old Quadrajets and the bottom plug in the main well will leak and the gas seeps out around the base gasket.
It's not as bad as it sounds and I've been running the blower and leaving the doors open when I go over there so it's much better than it was.
We're still a long ways from having it operational.

 

[Comodave]

On a gas powered boat that has gas fumes in it, my absolute first thing would be to stop the gas leaks immediately, not tomorrow but today. There is no way to confidently predict what might ignite the fumes. Just putting in a blower to evacuate the fumes isn’t a safe way to proceed, fix the leaks right now.

 

[BoatPoor]

On a gas powered boat that has gas fumes in it, my absolute first thing would be to stop the gas leaks immediately, not tomorrow but today. There is no way to confidently predict what might ignite the fumes. Just putting in a blower to evacuate the fumes isn’t a safe way to proceed, fix the leaks right now.

That's the plan but it's not my boat yet. I've got the carb kits ordered so as soon as the deal is done I can rebuild both carbs, but I've still got to replace the rattling/squealing blower and get the fumes/smell gone after the carbs are done.

 

[Comodave]

I didn’t understand that it wasn’t your boat yet. Then yours is a reasonable plan. Good luck. We are also in the process of buying a boat, we are on boat offer #3 now.

 

[GoneDiving]

I'm using a 12" industrial extraction fan similar to those used by welders or confined space entry. I found a model that has 2 speeds and would agree that a large fan running at low speed is much quieter than the reverse. I also have the option of running at full speed should the need arise.

Note I'm a large diesel not gas.

 

[rslifkin]

Any blower used on a gas boat needs to be ignition protected, so many of the options people use to extract heat from an engine room with diesels aren't usable here.

 

[Solly]

Have you found a marina or insurance company that will allow you to let out the boat ?
I'd look at that very closely from a liability standpoint..

 

[Marco Flamingo]

Any blower used on a gas boat needs to be ignition protected, so many of the options people use to extract heat from an engine room with diesels aren't usable here.

The fan can be just the spark that you didn't want. A blower on a diesel that has propane onboard should also be ignition protected.

 

[BoatPoor]

I didn’t understand that it wasn’t your boat yet. Then yours is a reasonable plan. Good luck. We are also in the process of buying a boat, we are on boat offer #3 now.

Best of luck, it can be frustrating.

 

[Comodave]

Best of luck, it can be frustrating.

Thanks. Went to meet with the seller today. He is having the headliner redone in the cabins. Unfortunately it won’t be done for a couple of weeks so we have the sea trial and survey scheduled for the 20th. Hopefully it goes well.

 

[BoatPoor]

I'm going to the marina this weekend and set my industrial shop fan up on the dock and open both sliding side doors to get some airflow going and pull the engine hatches to let it vent.
The boat isn't mine yet so I don't want to put any money into it yet, but the owner has given me permission to do pretty much anything I want until the documentation comes through. I've already tightened a prop shaft packing to slow down a leak, we've pulled all of the bedding to wash, done a bit of cleaning and tested every system/component I can think of so we can attack all needed repairs as soon as it's officially ours.

 

[Comodave]

Usually a good cleaning does a lot to help a boat come back.

 

[BoatPoor]

Luckily we don't have to do actual sea trials because ours is on a landlocked lake in N. Central Texas. It hasn't been driven in a couple of years but is in pretty decent shape from being in a covered slip the whole time.

 

[Bacchus]

Luckily we don't have to do actual sea trials because ours is on a landlocked lake in N. Central Texas. It hasn't been driven in a couple of years but is in pretty decent shape from being in a covered slip the whole time.

No sea trial? I don't understand the rationale.
Location has nothing to do with it... call it a lake trial or trial run. On gasser(s) I would also want to do a compression check as its fairly simple to do and can reveal info on engine condition.
Sitting for years isn't a good thing even if covered.

 

[FF]

If the boat will not operate often , if ever , you might contemplate simply removing all the fuel from the tanks , and perhaps the tanks too.

When operation is desires the portable style tank could bring fresh fuel , that could be drained into a car at the end of the operation.

If they make blowers for gas vessels,
https://deltatsystems.com/

 

[OldDan1943]

I wouldn't do any work on the boat until I owned it. If you get all the work completed and the sale falls through, you have your money and time invested. You do all this work and the sale falls through, the current owner can up the price when he puts it back on the market. May I suggest, it is the owner's responsibility to correct this problem as part of the sale.
A. I am not big on gasoline boats, they scare me.
B. Right now you have gas fumes in the bilge/engine room
C. Until the owner corrects the noted problem, I would put the sale on hold.

 

[BoatPoor]

OK, this sort of got sidetracked so here's the situation. I'm not currently doing any work on the boat until it's in my name, but I AM planning out what needs to be done.
I've spent 25+ yrs as an automotive master tech so the fuel leaks are just a minor annoyance at this point, I just want the smell gone out of the bilge and cabin. There are no raw fuel leaks, just seepage from sitting so long and when the engines heat up, it smells like old gasoline inside the boat. Think of an old lawn mower in a shed type of smell.
I just didn't't want to waste money on a crappy bilge pump, but I think I've figured out which one I'm getting.

 

[Marco Flamingo]

If it is just the odor, you might try something like PureAyre. Works for diesel and head smell, although nothing seems to beat a thorough cleaning and a few weeks of fresh air. Might still be a quick fix.

 

[Turtle Blues]

Sigh,
I keep hanging on hoping someone will respond to th OP's original question with a review of the sound levels of currently available bilge blowers.

 

[Lepke]

Long ago I ran some gas boats. The bilge blowers only need to be run for several minutes before starting an engine. They don't need to run continuously. It's important that any vent tubing to the blower extend to the lower bilge. That's where gasoline fumes will gather. Two blowers are better than one. Anytime you start the engines, the blowers need to run. Even if you just shutdown for a few minutes. The carbs should have spark arresters.

When fueling a gas boat, everything needs to be off. Nothing with a flame or with contacts that could spark.
About 60 years ago I saw a 65' gas boat blowup and it still scares me. Investigation showed the bilge blower switches were off and assumed not used. Boat was wood, ex-military aviation rescue, and was mostly splinters. Owner wasn't killed by the explosion or the fall from considerable altitude. But the sudden stop on the next dock did him in.
You're gonna burn a lot of gas in that boat.

 

[Leo Reise]

We replaced our 3" Jabsco (it was a model not designed for a constant run) wit a 4" 35760-0092. We run it whenever the engine is running. Estimated life expectancy 5000 hours. Cost in the $300 CND range. Seemed like a good trade off.

 

[Turtle Blues]

Hoping to find sound info on secondary use 4" round blowers. Want to quiet the exhausters in the galley and heads. Don't mind hearing the ER blowers - it reminds me they are on but the others are annoyingly loud.

 

[OldDan1943]

Hoping to find sound info on secondary use 4" round blowers. Want to quiet the exhausters in the galley and heads. Don't mind hearing the ER blowers - it reminds me they are on but the others are annoyingly loud.

Put them ashore.

 

[BoatPoor]

Long ago I ran some gas boats. The bilge blowers only need to be run for several minutes before starting an engine. They don't need to run continuously. It's important that any vent tubing to the blower extend to the lower bilge. That's where gasoline fumes will gather. Two blowers are better than one. Anytime you start the engines, the blowers need to run. Even if you just shutdown for a few minutes. The carbs should have spark arresters.

When fueling a gas boat, everything needs to be off. Nothing with a flame or with contacts that could spark.
About 60 years ago I saw a 65' gas boat blowup and it still scares me. Investigation showed the bilge blower switches were off and assumed not used. Boat was wood, ex-military aviation rescue, and was mostly splinters. Owner wasn't killed by the explosion or the fall from considerable altitude. But the sudden stop on the next dock did him in.
You're gonna burn a lot of gas in that boat.

The boat is equipped with spark arrestors and I am aware of the blower guidelines, although I may wire in a timer circuit so that the engines and generator won't start without a minimum blower run time.
You are correct about the fuel consumption, if we decide it's worth keeping I will probably ditch the carbs for stand alone fuel injection. It probably won't leave the slip very often and I'm not looking to win any races with it, but the tunability, fuel economy, and reliability are nice.

 

[BoatPoor]

Sigh,
I keep hanging on hoping someone will respond to th OP's original question with a review of the sound levels of currently available bilge blowers.

I ended up purchasing one from Chillout Systems and so far couldn't be happier. Once I got seriously into the bilge areas I discovered that this boat actually has a total of four bilge blowers. There are two in the aft bilge where the original Genny is and two more in the engine room.
This blower was purchased on Amazon (I know...) for around $56 and it's quieter than the other three Atwood blowers.