Joe wrote:
On Jul 29, 4:55 am, "Roger Long" wrote:
An interesting thing about the Yanmar 2QM series is that there is no return
line back to the tank. Evidently, the injector bypass just circulates back
as far as the injector pump on the engine. It is an unusually cool running
engine for a diesel so maybe that helps avoid the fuel getting too hot.
Flow through the filter is whatever fuel consumption is.
Just out of curiosity, I'm going to look at recommended flow rates on some
separator filters but I'll be surprised if any
go as low as 1 gph. It's appears to be a centrifugal process judging by the
spiral grooves I see on some of the filter housings so it must take a
reasonable flow. Just out of curiosity, I'm going to look at recommended
flow rates on some separator filters but I'll be surprised if any go that
low.

Chris had a good point, now that I'm putting an emulsifier
(StarTron/Soltron) in the fuel, The water isn't going to separate out
anyway.

--
Roger Long

Quick Question: Just where oh where is the water going to go to?
Emulsified out of existance?

I'm getting into your fuel problem a bit late Roger, whats up?
You got alge problems?

How long has the fuel been on your boat?
How many gallons do your tanks hold?
What are your tanks made of ?
Do you have access through an inspection plate?
Tanks baffled?


In the USA the major source of water in your fuel is condensation of
the moisture in the air in the tank, collection on the tank top then
dripping into the fuel. Best way to keep moisture out with the boat
sitting most the time is to keep your tanks pressed full.

Alge killers present thier own problems and none do a proper job IMO.
Your options are to slosh out the alge and buy filters by the case
until it's all gone, or clean the tank. Once I picked up a 120'
crewboat that had been in Mexico for 3 years and had the worst alge
problem in a fuel tank that ever existed, so bad the water traps would
not drain due to getting clogged with alge, had to poke the drain
spigots with a hanger wire to break the crap up to drain the water. We
used up a couple grand in filters before we got it cleaned up, we
burned 180 GPH, with a 4000 gallon tankage. The boat had aluminum
tanks that were the deck in the passenger area that was always kept
cold, the boat rocking and sloshing allowed the tanks to breath in and
out moist air all the time, creating massive amounts of water due to
condensing on the tank tops.

So what's it like to go that deep under the ocean?

Joe




Here's what David Pascoe has to say about condensate in fuel tanks!
http://www.yachtsurvey.com/myth_of_c...fuel_tanks.htm

Interesting
Gordon

"Roger Long" wrote in message
...
"Joe" wrote
Quick Question: Just where oh where is the water going to go to?
Emulsified out of existance?

It will go through the engine. If the surfacant can distribute it finely
enough through the fuel, it will just vaporize in the combustion process
with a slight loss of performance and maybe some additional wear on the
injectors. It' s when it's rolling around in slugs that go down the fuel
line so that the engine tries to run on nearly pure water for short
periods that you have a big trouble.


I'm getting into your fuel problem a bit late Roger, whats up?
You got alge problems?

I haven't had any problems but am just trying to head them off.

The boat was stored hauled out with fuel in it for six years before I
bought it and everything had turned to jelly. The PO paid to have it all
cleaned out and the tank polished. I than ran it for two and a half
seasons without giving it a thought. The sediment bowl remained crystal
clear until a few weeks ago when I spotted just a few specks of alge and
realized it was time to start being proactive. The engine missed about
three beats around this time (which prompted the look at the filter) when
the tank was down to about minimum.

I put in the StarTron and the sediment bowl turned immediately solid
green, as it should. I changed the filters and the engine continues to
purr.

I find myself often motoring along close to sheer cliffs since looking at
the shorline and wildlife is a major crusing objective for me. I'm
planning to do this in Newfoundland after the current research vessel
project is finished so I'm starting to really take an interest in the
subject of keeping engines running. I've previously had a fairly casual
attitude because I have those dacron "take home" engines up on the spars.

My fuel tank is quite high in the hull and far from the cold hull surface
so I probably don't get any significant condensation. It's not generally
a big problem in this climate anyway and fuel quality is pretty good.

--
Roger Long


Ya, the time to think about algae and water is before it becomes a problem,
not after. For my part, I think all diesel should be treated at fill-up.

This is quite consistent with my experience managing an aircraft with
aluminum tanks. We stopped filling up after every flight and saw no
increase in water. I only saw water a couple time in nearly a decade of
flying and it was religion to sump the tanks before every flight. I only
saw water after rains heavy enough that a thick water film could have built
up around the caps by coming down faster than it could drain off the wings.

--
Roger Long

"KLC Lewis" wrote

Ya, the time to think about algae and water is before it becomes a
problem, not after. For my part, I think all diesel should be treated at
fill-up.

I will from this point on.

--
Roger Long

Roger Long wrote:
:Hmm, no minumum flow rates indicated on the Racor site specifications page
:for water separator filters.

Why would there be? The seperation is done by gravity. Diesel floats
on water, so the water collects on the bottom of the bowl, where it
can be drained out the handy valve on the bottom.

"David Scheidt" wrote


Why would there be? The seperation is done by gravity.

Undoubtedly. Someone else raised the minimum flow question which seemed
plausible to me only because of seeing spiral grooves on some of the bowl
housings that looked as if the centrifugal effects of flow might be intended
to assist gravity. Maybe so but it apparently isn't a big enough
contribution for Racor to warn against diminished performance at low flow
rates.

A more likely probabiliy now seems to me to be that the grooves are intended
to slow the flow so that gravity will have more time to do its work. I'm
skeptical now that there is a downside to a large filter.

--
Roger Long

On Sun, 29 Jul 2007 18:33:40 -0400, "Roger Long"
wrote:


"David Scheidt" wrote


Why would there be? The seperation is done by gravity.

Undoubtedly. Someone else raised the minimum flow question which seemed
plausible to me only because of seeing spiral grooves on some of the bowl
housings that looked as if the centrifugal effects of flow might be intended
to assist gravity. Maybe so but it apparently isn't a big enough
contribution for Racor to warn against diminished performance at low flow
rates.

A more likely probabiliy now seems to me to be that the grooves are intended
to slow the flow so that gravity will have more time to do its work. I'm
skeptical now that there is a downside to a large filter.

The flow rate is fixed by the flow rate...as is the "time of flight"
from inlet to outlet. Perhaps they are making a vortex. Just a guess.

"Goofball_star_dot_etal" wrote in message
...
The flow rate is fixed by the flow rate...as is the "time of flight"
from inlet to outlet. Perhaps they are making a vortex. Just a guess.


A vortex is claimed, but whether or not it is actually there, and whether or
not it actually separates water, is another matter entirely.

On Sun, 29 Jul 2007 11:59:01 -0400, "Roger Long"
wrote:

it was religion to sump the tanks before every flight.

Interesting. Although not recently, I've had some experience flying
in private aircraft and don't remember ever seeing that done. Sounds
like a good idea though. Do you drain it into a transparent cup like
I do with my Racors?

Yikes, you flew with someone who didn't sump the tanks? It's so universal
that it would make me wonder what else he wasn't doing. Were you there for
the whole pre-flight or did you just get in after the plane was ready? I'm
sure the tanks were checked. I've heard of a lot of dumb flying tricks but
never not checking the tanks.

The sumps are a valve that opens when a rod is pushed in. There is a nifty
little jar with a rod held in the middle so that the fuel pours in. You
then check for the proper color, sediment, and water. It used to be that
you then threw it on the ground and many still do. Because of the lead,
more and more pilots are now using sample jars with a mesh screen that
filters out water so that the fuel can be poured back in the tanks. You
want to visually confirm their level anyway.

--
Roger Long