Fuel Polishing

[jr438234606]

Hi All,

I am in the early stages of putting together a fuel-polishing system for my diesel. I need a number of tees, shut-off valves, check valves, hose barbs, etc, etc. I've located a supplier for these items, but some of the items are made of brass and others are made of bronze. For example, the Tee may be made of bronze, and the Hose Barb to connect the Tee to the hose may be made of brass.

I'm concerned about galvanic corrosion between the two metals. Would it be a big mistake to intermix the two? Since there is no persistent electrolyte present, would it not be a problem?

[tmhdgpth]

You'll find a copy of the galvanic chart here:

http://www.engineersedge.com/galvanic_capatability.htm

It shows brass and bronze well within the limits for a harsh environment. Good luck!

[Cruisingdad]

TMH,

Nice chart!! I will have to keep that one saved!

[kimberlite]

available from mcmaster carr
fair winds
eric

[Trekka]

I'd be interested in the specs on the system you are building. What components, etc.

[DelmarRey]

Originally Posted by kimberlite

available from mcmaster carr
fair winds
eric

$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

[sailandoar]

Conductive electrolyte is what allows dissimilar metals to interact. If you mix metals and the boat sinks "IN SALT WATER" and a year or two later the boat is salvaged then the EXTERIOR of the fittings may be corroded but the interior, coated-with / floating-in diesel fuel should be fine and dandy.

Always good to use the same metals when possible but it is one of those things that should not stop or slow a job unless 'paralyzed by perfection' is a requirment of the job contract.

Note:
(1) you asked about all copper alloys, no problem... If you were to throw in a steel fitting it would work but eyebrows go up and if you added an aluminum fitting it would work and maybe forever but it would be a streach and would be frowned on.
(2) some waters are fairly acidic and so in designing the piping system, maintaining similar materials becomes important, however in that case you would likely use plastic.

[SmartCaptain]

Good morning,
I have a fuel polishing system made from Racor 500's, Tempo 3-way fuel valves (br, I think), Walbro pump and misc. hardware store plumbing fittings (brass/bronze). I've used this system for five years with no apparent problem. All fittings are in a dry engine compartment and my fuel has almost zero water in it.

Hope this helps,

Jeff

[SAILAMEL]

Sometime during almost every passage, I hear that someone’s engine died
after going through all of their fuel filter inventory and clogging up their
injectors. I towed a boat into Bermuda this spring with exactly this problem.

News Sunday, May 7, 2006 Contact us



Bermuda Gazette

Yachts towed into Island

Two yachts had to be towed into St. George’s harbour after suffering engine failure yesterday.
The first was a UK-registered 31-foot sailboat called the Sea Gypsy which had sailed from St. Maarten and was on its way to the Azores. It requested assistance shortly before midday as it arrived off Bermuda. It was eventually towed in by the US-registered sailboat Kimberlite which noticed the yacht was in trouble as it was making its way out of St. George’s Harbour.


The gunk that STICKS to the bottom of an American made fuel tank will
not be removed by simply circulating the fuel through another filter system.
the trouble happens offshore when a boat really starts rocking and rolling
and breaks up the sludge on the bottom of the tank.
Most USA systems use a pickup tube that is anywhere from 3/4" to 2" off the bottom of the tank. This leaves a lot of room for sludge.
I always polished my tank on my old boat by making a wand out of soft copper
Tubing and using that as a pickup I sweep the bottom of the tank and then through a Racor turbine filter and a Jabsco Vane pump. Then back into the tank.
This is all accomplished through the fuel gauge hole. To get around the baffles you need inspection ports.

My current boat is European and the fuel comes off of the Bottom of the Tank thus no crud buildup. Incidentally BioBor and such products Just kill the bacteria etc and leaves more gunk in the tank.

I also have a pre filter system where I pump my incoming fuel through a
Humongous Racor filter and then through a 16gpm pump and into the tank.
Thus no water to grow bacteria.
If you would like to see a pix of this E-mail- me at Kimberlite@optonline.net
Fair Winds,
Eric
Amel Super Maramu #376 Kimberlite

[Rockter]

Be very careful about using stainless.

In absence of oxygen, and some salt water in there (with chlorides), stainless is a very unforgiving material indeed.

I don't recommend you try it, but if you filled your water tank with salt water, and put a cork in the top of the tank, it will leak like a sieve in no time. Stainless in the presence of water MUST BE OXYGENATED.