Let's play what's in this fuel sample?

I guess my dogged interest in this thread is that I have had the exact same problem and I don't want it again, so please forgive the nit-picking. My tanks are plastic, my lines are rubber and the fittings are stainless steel. Where is this rust coming from? Certainly not the source of the aviation gas which I would think/ hope is held to a higher standard than automobile pump gas (which I believe to be the source of my problem). If this was a common occurence even with occasional use I would think the FAA would be all over it. I'm in a very cold climate too and my boat sits in an unheated space all winter so I can understand condensation but not the rust color, or the huge quantity that I removed, literally more than a quart.
 
Fairbro,

Accumulated condensation from repeated hot/cold cycling of air in fuel tanks is capable of generating some moisture over a long layoff season. As to the "rust," could be it is an organic material and not derived from a ferrous material. For an analysis on how much water can be ducted in via repeated condensation, and ideas for other sources of the water and the rust, check this guy out; I'd guess he underestimates the problem, because of repetition many days in a row. But, his math for one cycle is pretty close, I think: http://www.yachtsurvey.com/myth_of_cond ... _tanks.htm

I'd guess the fuel filler closure is the most likely for huge amounts of water with an improperly installed vent fitting (and line -- no loop) in second place, but this really is a crap shoot.

A small amount of iron oxide can "color" a huge quantity of water, so a small amount of rust could cause that appearance.
 
Regarding the fuel filters ON/IN the Honda motor. Certainly they need changing, and I would suggest once per year.

Remember there are two of them: one low pressure where the fuel hose enters the engine, AND the high pressure filter near the vapor separator. Certainly check the water bowl for sediment, etc.

No, they're not cheap, but if they're plugged, the engine will not run right, and spares aren't easy to come by. There aren't too many Honda dealers in the back woods. Try Honda Parts for some discount.

Boris
 
I've done lots of googling and think I may have a lead on the brown liquid. It may be the result of surfactants.

The term "surfactants" is a contraction of "Surface Active Agents." These
soap or detergent-like materials occur naturally in fuel. They may also
be introduced in the refining processes by the inclusion of additives into
the fuel, or they may be washed off the internal surfaces of containers
previously holding other products. Surfactants are usually more soluble
in water than in fuel and reduce the interfacial tension between water and
fuel; this stabilizes suspended water droplets and contaminants in the
fuel. Surfactants adhere to filters/separators and reduce their
effectiveness. They also adhere to metal surfaces until surfactant-rich
water droplets are formed. The droplets run down the sides of fuel tanks
and form puddles in the bottom or in the sumps. Surfactants in large
concentrations usually appear as a tan to dark brown liquid with a
sudsy-like water/fuel interface.

Now I confess I have added "SeaFoam" to the fuel when the engine was running rough and it immediately improved engine performance but longer term it may also be the cause of the "brown liquid" :oops:

So that's my best guess. I've still got about 25 gallons of "SeaFoam enhanced" fuel on board. I'll continue to take samples from the Raycor. I suspect I'll still need to polish the fuel with something like the "Austin Fuel Polisher" :lol:
This morning, with the new filter, the Honda was purring like new and there is no residual brown liquid in the filter :thup

Phil
 
Good work and nice find, Phil!

Glad to hear the "kitten" is back to purring! :cat

Joe. :teeth :thup
 
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