Engine room mounted air compressor

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Has any body installed an air compressor in there engine room for blowing up water toys and using air tools. If so, what kind and size. All info would be greatly appreciated.
 
I put in a cheapo oil less pancake comp in my engine room. There is an air chuck in the cockpit and in the ER, also powers the air horn. Very handy. 120V, bought from Lowes or similar for like $120.

It does not run air tools like a DA for very long before it needs to pump up again. Not sure of the capacity.
 
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Has any body installed an air compressor in there engine room for blowing up water toys and using air tools. If so, what kind and size. All info would be greatly appreciated.
Yea same as ski, i have a cheapo in the er. Tiny tank, but i have a 5gal reserve tank under the flybridge helm. You need a fairly large inverter to handle loaded startup. If i use the horns alot on a hot day, sometimes it will trip the inverter.
 
The tank is the key. If you can find room for a 5 to 10 gal tank you will have all the air you need for many purposes including lots of air tools. The compressor might take a long time to top off the tank but it can do that while you are off doing something else.

Air tools like Sanders and grinders use too much air to run off a small compressor. Tools like hammers, guns and ratchets use very little air. Spray guns for small jobs.
 
What about a compressor belt driven from a PTO with a tank located somewhere else?
I was always wondering if I could fit one on my existing pulleys that could fill a tank on the flybridge.

L
 
Greetings,
We have a smaller compressor in the ER from a big box store (Ace/HD). About $100. As Mr. Ski notes, short run time for air tools. Good for cleaning/dusting mechanical "stuff". We have enough hose to reach all of boat.
 
When picking your tiny air compressor, make sure to get one with an aluminum tank, since a steel tanks rust, especially when you compress moist air, it separates the condensate into the tank and that starts rust unless you drain the tank often.

A 100 PSI 5 gallon tank of air can blow your boat up if it explodes. I was near a gas station when their tank blew the roof off the station and left an 8x8 foot hole. Who knows how high the tank parts flew in the air...

So, get an air compressor with an aluminum tank, and drain it regularly to keep moisture from building up in the bottom.
 
What about a compressor belt driven from a PTO with a tank located somewhere else?
I was always wondering if I could fit one on my existing pulleys that could fill a tank on the flybridge.

L

I doubt you have a need for that much air power, to run the risk of a direct driven compressor...

If it were me, I think I would check out one of these models:
https://www.amazon.com/California-Air-Tools-12V1P10S-Compressor/dp/B083VNH2BF

It has an aluminum tank so no rust, and is fairly quiet, and it runs on DC so can run when necessary off the batteries, just put a Low voltage disconnect on the power cord.
 
I doubt you have a need for that much air power, to run the risk of a direct driven compressor...

If it were me, I think I would check out one of these models:
https://www.amazon.com/California-Air-Tools-12V1P10S-Compressor/dp/B083VNH2BF

It has an aluminum tank so no rust, and is fairly quiet, and it runs on DC so can run when necessary off the batteries, just put a Low voltage disconnect on the power cord.

I keep that very model on board. Great compressor- ultra quiet. Doesn't take up much space.
 
I am not sure what the PO was thinking on Libra but she has a direct drive compressor on the main and genny, and a separate 220 v stand alone variety.
Other than an air horn, not sure what he was after.
 
Notice the warning label near the drain plug. Recommended to drain daily or after each use, so if you do that it doesn't much matter if it's steel or aluminum.

Yessir.
 
My MT came with a silent JunAir compressor. I took it out and its for sale in the classifieds section. It was a good unit as they are silent and very efficient. Fast recovery too. I wanted the space for something else. Hope I do not regret it. They are $pendy compressors new.
 
We installed a vent on our air compressors, so whenever the motor ran, it vented for 2-3 seconds, triggered by starting the motor. That opened the drain enough to blow out any condensation.
I guess I switched from the AC with aluminum tank version to the DC steel tank version.

I guess you could use air-on-demand compressors with no tank and minimize your risks.

Anyone with an air powered horn runs the risk of a tank problem, since you're going to leave the tank pressurized all the time, in the event of needing your horn. The more the compressor runs, the more it will fill the tank with condensed water.
 
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We installed a vent on our air compressors, so whenever the motor ran, it vented for 2-3 seconds, triggered by starting the motor. That opened the drain enough to blow out any condensation.
I guess I switched from the AC with aluminum tank version to the DC steel tank version.

I guess you could use air-on-demand compressors with no tank and minimize your risks.

Anyone with an air powered horn runs the risk of a tank problem, since you're going to leave the tank pressurized all the time, in the event of needing your horn. The more the compressor runs, the more it will fill the tank with condensed water.




I use "disposable" tanks for my air horn. Only turn it on before a cruise. I use a 20lb propane tank. Works great and can swap it out for cheap every 6-8 years. :)
 
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I'm sure the motors on the box store compressors are not ignition protected, so not in the engine room if you have gas engines. But even though we're talking diesel, isn't this a concern and is it permitted per ABYC?
 
We have a compressor for the air horn, and have plumbed that to an outlet or two for utility use.
 
I'm sure the motors on the box store compressors are not ignition protected, so not in the engine room if you have gas engines. But even though we're talking diesel, isn't this a concern and is it permitted per ABYC?


Even with ignition protection, no compressors in the engine room of a gas boat IMO. You wouldn't want to suck up and compress gas fumes in the event of a leak. If I ever add one on my boat, it would have to go in the forward bilge, as that's the only bilge / utility area that doesn't have gas tanks, lines, engines, etc.
 
I'm sure the motors on the box store compressors are not ignition protected, so not in the engine room if you have gas engines. But even though we're talking diesel, isn't this a concern and is it permitted per ABYC?
None of your er equipment is "ignition protected" on a diesel boat.
 
Notice the warning label near the drain plug. Recommended to drain daily or after each use, so if you do that it doesn't much matter if it's steel or aluminum.
Yes you need to drain. Add that to your daily engine room checks.... oil levels etc. If you use it for other things besides a horn, yes you need to go drain it. That is any air compressor.
 
And tanks should be monitored for condition. If drain water starts getting rusty or the tank is just old, it's time to think about replacement. They're not forever, even aluminum tanks (they still corrode and they're more likely to wear out from fatigue after enough pressure cycles).
 
It is very rare for air tanks to explode violently, although it does happen. Usually if corrosion gets bad, you will see pinhole leaks with a rust stain below. Sometimes the pinhole leaks a bit, then the corrosion seals it back up. It is still badly corroded inside.

So if you see rust stains on your air tank, get rid of it. Even if you detect no active leak.

On my boat the air system plumbing leaks a tiny bit, so in a couple days with comp off, pressure bleeds down. I'm not worried about the tank exploding.

I would not spend the extra for an Al tank. Al corrodes too, just differently, and not necessarily slower. Steel will last long enough for most of us!!

And yes, these things are not ignition protected. Both pressure switch and most use universal (brush type) motors. No go for a gasser engine room, but fine for diesel.
 
Water Toys

I use a Portable battery operated shop Vac for blowing up the toys and the dingy. But for work tools I use the same battery operated tool Impact, drill driver, and so on. Now a days you can buy a complete collection of strong battery operated tools and if you look around you could have two or three extra batteries for quick charging as you are using one!
https://www.amazon.com/Ryobi-P1819-...rds=ryobi+battery+tools&qid=1615575747&sr=8-5
Here is the shop vac
https://www.amazon.com/18-Volt-Proj...ds=ryobi+battery+tools&qid=1615575841&sr=8-33
Gregg
 
Buy a compact automobile compressor on Amazon. They charge on 12v, and have decent battery life too!
No need to take up space with an air tank?
 
You can buy a valve that automatically drains an air tank whenever the pressure is released. I've had air tanks on boats about 60 years. I never had one fail.

Advantages of having air on board is a real horn, or a steam whistle, air tools, spray painting, sand blasting, and the usual filling tubes, etc. An air sander is much quieter than a powered one and the noise is far away in the engineroom.

I have air shifting and air throttles, so have to have air.
 
I doubt you have a need for that much air power, to run the risk of a direct driven compressor...

For the very few that need a lot of air all the time many industrial engines have road going equivalents that come fitted with brake air compressors. Retrofitting would be simple.

I'd agree that for 99.9% of the time electric would be easier, cheaper and probably higher flow. A commercial vessel needing lots of air will already have a large genset.
 
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