compressor for sailing

[pescador775]

I thought that that was in the content of the detailed post. Oh well. You need a Bauer PO filter/condenser. That thing is fairly large and you need to check if it will plumb in the space between the pump shroud and the gas engine. No need for a new backpressure valve but you will need to install the old one on the new filter and check the valve for its pressure setting . It is adjusted by turning a thin nut with a plumber's wrench (looks like a tuning fork) and then, by using a special tool that looks somewhat like curved pliers, turn the cap SLOWLY clockwise until desired pressure of 2000 psi is reached. Be careful, the valve is pre loaded with four wave springs and can fly apart if unscrewed. That should be it provided that the pump and engine are in good condition. Otherwise, you will need a special tool set (pin indexed spanners) from Bauer. These are normally supplied with the compressor at purchase. Then you will most likely need to replace the third stage valves. These unscrew using the spanners. The photos show a Bauer Purus/E3 in apparent excellent condition. The filter appears to be the old type of limited use. The internals of the filter need to be inspected. Report back when you know what is inside that tube. It may be possible to add something on rather than purchase a $500 PO from Bauer. Clean air is important to the life of your tank and will save headache later.

Thanks for the detailed response, I plan to go pick up the compressor this weekend (On an ironic note, I will prbably spend almost as much on gas to go get it as the unit is costing me), after I get it in hand I will be in a better position to ask detailed questions. If this unit is like the '76 model you refer to, what upgrades would you recomend before putting it in service?

Thanks Ike

p.s. I have copies of the photos from the orignal ad posted at www.beau.lib.la.us/~ikes/compressor perhaps you can tell something about the filters, etc. from this.

 

[oxyhacker]

Really old or badly fried oil getting past the rings in more than acceptable/usual quantity, carbon deposits letting loose, or combustion byproducts.

Which problems cause what change in appearance in the condensate?

 

[pipedope]

Clean air is important to the life of your tank and will save headache later.

I am far more concerned with the health of my lungs and me in general. If the air is good for me it won't hurt my tank.

 

[oxyhacker]

Most of these smaller filters used nothing but charcoal originally originally which is not acceptable by modern standards, however Lawrence Factor makes replacement disposable cartridges for some them which have both drier and carbon and last thing I knew Bauer still stocked a refillable cartridge to fit them which can be handpacked with modern fills using cheap bulk media. Both are good by current standards for only 5-15 tankfuls, which could get pretty expensive or tedious in the long run, but can be a useful stopgap to get the rig up and running while he prices alternatives.

Highly recommended anyone using small filters like these and/or an IC engine get an Aqua Environment eyeball detector with the water/CO element to monitor filter condition.

BTW $500 sounds cheap for a PO - last time I priced one it was closer to $800 best I can recall. You got a secret source?

The filter appears to be the old type of limited use. The internals of the filter need to be inspected. Report back when you know what is inside that tube.

 

[pescador775]

They're up to $800? Peeyew! Better that this situation with the Purus filtration system be investigated before making a move on that. You may recall that I favor redundant filtration instead of a single can, even for portables. Again, doing my own tests I have come to the conclusion that the first stage of filtration should consist of a condenser with backpressure valve followed by a chemical filter. This 'precompresses' the air, releases a lot of heat and charges the chemical filter with cold, dry air. There should be room on that Mako/Purus frame for an extra can (condenser + bpvalve). The existing condensator could be plumbed downstream and packed with a chemical cartridge from Lawrence factor or rearranged internally and hand packed. Should be good for 50 fills. The reason that the filters contained in large condensators like the PO do not last as long as expected is due to residual water and humidity which lays in the bottom of the can. This cannot be expelled completely and remains to cause slow damage to the expensive filter canister. This is compounded by atmospheric humidity if the drain valve is left open.This does not happen when the air is precompressed and scrubbed before it reaches the (separate) filter. When not in use the final filter is capped and remains dry.

Most of these smaller filters used nothing but charcoal originally originally which is not acceptable by modern standards, however Lawrence Factor makes replacement disposable cartridges for some them which have both drier and carbon and last thing I knew Bauer still stocked a refillable cartridge to fit them which can be handpacked with modern fills using cheap bulk media. Both are good by current standards for only 5-15 tankfuls, which could get pretty expensive or tedious in the long run, but can be a useful stopgap to get the rig up and running while he prices alternatives.

Highly recommended anyone using small filters like these and/or an IC engine get an Aqua Environment eyeball detector with the water/CO element to monitor filter condition.

BTW $500 sounds cheap for a PO - last time I priced one it was closer to $800 best I can recall. You got a secret source?

 

[pescador775]

It would appear that you are stating the obvious. However, SCUBA tanks act like a condenser. Heavy contaminants, those other than gaseous types like CO, precipitate in the tank and rarely are present in the breathing air in quantities which are unhealthful. Water vapor, a gas, may be present in the breathing air. In fact, the increased humidity of a wet tank might even be considered beneficial to the diver. The problem for the diver's health is from rust deprived oxygen levels, from crud entering the regulator, jamming the filter or damaging the HP seat, and from the possibility of a tank explosion. What's good for the tank is good for you, not the other way around.

I am far more concerned with the health of my lungs and me in general. If the air is good for me it won't hurt my tank.

 

[oxyhacker]

Hmmm......
Maybe the thing to do is forget about drying/filtration on the compressor, and just put a bleed valve on the bottom of each tank!

It would appear that you are stating the obvious. However, SCUBA tanks act like a condenser. Heavy contaminants, those other than gaseous types like CO, precipitate in the tank and rarely are present in the breathing air in quantities which are unhealthful.

 

[ChrisA]

My uncle just bought at 50' boat in the Carribean and I am going to be heading up the crew. I am a DM and am beyond excited about the prospect of sailing around the Carribean and doing all the diving I want, but I am now realizing that we need a compressor and tanks. There will be max 4 people diving off the boat, so we don't need anything big, but we want something that will do the job reliably. So, does anyone have any recommendations? The boat is located in St. Maartin, and we will have to buy the compressor somewhere in that area. How much should we expect to spend? Any brand or model recs? Thanks so much for your help!

I've got a sailboat too. Just some comments:

No way will an electric drive unit work without a huge battery bank and genset and inveter. You want an engine driven unit uless the boat is already so equipped

Diesel or gas? I can't imagine a sailboat owner wanting gas.
The stuff makes heaver then air fumes that will flow down
an open hatch into the living space and bilge. Would you fill
your outboard engine on deck? From a safty point of
view diesel is best. Gas is explosive, should only be used in
open air that is NOT above a closed compartment.

Put the compressor in the engine compartment and plumb the exaust like the main engine to a through hull on the transum and a small
water lift muffler in "standard" sailboat fashion. I think you
could route the intake up to the spreader or higher.
I think the compresser diesel can share a seawater intake with
the main engine through hull

But then a boat your uncle's size may have a genset lthat is sized
to airconditioning. If so you've got power to spare if you turn off
the A/C and the genset would likely be a water cooled diesel.
A 10Kva genset is not uncommon on large boats.

The boat when anchored should be head to wind so the intake will be 30 feet above and 30 feet windward of the exaust. Even if
you get the electric compressor to run off a genset you still need
to think about exaust as the compressor will need a running genset.
so you'd still want the intke up the mast Worst case is running in
a downwind slip, but then maybe you have shore power.

 

[pescador775]

You are overthinking the problem. For one thing, the compressor will have trouble drawing sufficient air from a 30 foot tube. It can draw about 90% but requires more power from the engine. Most Bauer compressors have a built in 'flow restrictor' and adding a long tube may be conterproductive. Ten feet is about optimum. For Isaac, forget the diesel engine and all the other stuff. Run the little Purus off a 3.5HP Briggs gas engine. Run it on deck. Make a canvas cover with tie downs.

BTW. Margo bought a Bauer Junior, went on her trip and later, sold the compressor.

I've got a sailboat too. Just some comments:

No way will an electric drive unit work without a huge battery bank and genset and inveter. You want an engine driven unit uless the boat is already so equipped

Diesel or gas? I can't imagine a sailboat owner wanting gas.
The stuff makes heaver then air fumes that will flow down
an open hatch into the living space and bilge. Would you fill
your outboard engine on deck? From a safty point of
view diesel is best. Gas is explosive, should only be used in
open air that is NOT above a closed compartment.

Put the compressor in the engine compartment and plumb the exaust like the main engine to a through hull on the transum and a small
water lift muffler in "standard" sailboat fashion. I think you
could route the intake up to the spreader or higher.
I think the compresser diesel can share a seawater intake with
the main engine through hull

But then a boat your uncle's size may have a genset lthat is sized
to airconditioning. If so you've got power to spare if you turn off
the A/C and the genset would likely be a water cooled diesel.
A 10Kva genset is not uncommon on large boats.

The boat when anchored should be head to wind so the intake will be 30 feet above and 30 feet windward of the exaust. Even if
you get the electric compressor to run off a genset you still need
to think about exaust as the compressor will need a running genset.
so you'd still want the intke up the mast Worst case is running in
a downwind slip, but then maybe you have shore power.

 

[ChrisA]

You are overthinking the problem. For one thing, the compressor will have trouble drawing sufficient air from a 30 foot tube. It can draw about 90% but requires more power from the engine. Most Bauer compressors have a built in 'flow restrictor' and adding a long tube may be conterproductive. Ten feet is about optimum. For Isaac, forget the diesel engine and all the other stuff. Run the little Purus off a 3.5HP Briggs gas engine. Run it on deck. Make a canvas cover with tie downs.

BTW. Margo bought a Bauer Junior, went on her trip and later, sold the compressor.

Sailboats are not dive boats. Your typical dive boat is what you might call a "run about" suitable for good weather trips for a couple hundred miles. A 65ft sail boat is capable of taking a trip through the Panama cannal and heading to New Zeland, pretty much non-stop and dealing with whatever the ocean does to it on the way. Even if the owner would never do such a trip almost all owners take the effort to maintain the boat such that it could. My guess is that the owner simply would not want a portable gas engine on deck.
The typical sailboat will have a cabin roof 18 or 20 inches above
the deck. Believe me, exaust and gas fumes will find a way into the space below.

First off, where to store it while it is not in use? No you can't keep it
on deck, Sailboat decks take tons of water while the boat is under way. (Sailors _like_ to go out in 20 knots wind and big waves.)
And sailboats, while being sailed (as opposed to motored) need the deckspace for the crew to work and for lines, poles, sailbags and
what have you to move around.
You'd need a cockpit locker with chocks and hold down straps installed. But on a sailboat locker space is very valuable.
a 60ft sail boat will have only 1/3rd the space of a 40 ft diveboat
as the cabin roof willbe 5 ft above the waterline with no decks above.
I'd bet the engine compartment would be the best place. and now you are into a permenent installation. Cruising sailboats that
have compressors almost always mount them perminently.

I'll bet the electric powered model is the one to get as a boat that
size would likely have a diesel genset