On Sun, 12 Aug 2007 08:20:15 -0400, "Roger Long"
wrote:

In 38 years around boats with auxilliary engines, I've never actually
experienced a clogged fuel filter so I'm curious what the first signs are,
at least for slow build up as opposed to the fuel line suddenly sucking up a
mess that's been kicking around in the bottom of the tank.

I would expect that slowly developing problems would first show up at
maximum RPM and fuel flow and that the engine would continue to run properly
for a time at lower power. If I make it a practice to bring my engine up to
full RPM at least once during every run, I should first see a failure to
reach the usual number, perhaps accompanied by some smoke due to the
injectors not getting enough fuel for the rack setting. Backing off to my
usual cruising fuel flow, which is about 60% of WOT, should give me plenty
of running time to get to a place where I can safely change the filter.

Next year, I'll put in a vacuum gauge but, in the meantime, will this
strategy work?

There are two circumstances where you get clogged fuel filters. One,
you are running dirty fuel and the filter is doing its job and
filtering out all the little bit and pieces that come down the line.
In this case the symptoms are a loss in power.

The second case is where you have a substantial amount of water/sludge
in the tank and that suddenly gets into the fuel inlet. In this case
the engine stops right now!

The first case is pretty common where you are using dirty fuel, we ran
into it constantly working in the jungle where we were refueling from
drums. The fuel we were buying was probably not very clean and
dragging the refueling hoses around on the ground certainly didn't
help any either. The equipment operator would come in for lunch
bitching that "the damned thing doesn't have any power" and we'd go
out and change the filter.

The second case is catastrophic in that the entire fuel system from
the tank through to the injectors will be full of water/sludge. You'll
have to bleed the tank and fuel line all the way to the injector pump
and then disconnect the injector lines and motor over the engine until
you get clean fuel that through the injector lines and (invocations
to the Engine Gods help at this point) connect the injectors and hope
that you can get it to light off.

If you are getting "dirty" fuel there isn't much you can do except try
filtering it before you pump it into the tanks. The second case can
*usually* be overcome by draining the tank sump before starting the
engines.


Bruce in Bangkok
(brucepaigeATgmailDOTcom)

My neighbor, the fuel polisher, will tell you that you won't know you
have a developing problem until you hit some rough seas and stir up the
crap in the bottom of your tank.
Of course, then it's too late and at the worst time.
Gordon

"Gordon" wrote in message
...
My neighbor, the fuel polisher, will tell you that you won't know
you have a developing problem until you hit some rough seas and stir
up the crap in the bottom of your tank.
Of course, then it's too late and at the worst time.
Gordon

Motor boat talk!

If the seas are rough it means there's wind. If there's wind you use
your sails and not your motor. I can always tell who the pretenders are
by their knowing that rough seas cause diesel problems because there's a
blender at work mixing all the crud at the bottom of the tank with the
fuel.

I've also noticed that diesel boat people have this motor = security
blanket syndrome. You see them, even at anchor, when the wind pipes up
on goes their motor. I think they have this idea they can motor forward
to reduce the tension on the rode. But, boy oh boy, why not just get
ground tackle you can depend on? Running the motor and taking it in and
out of gear might be the worst thing you can do during a blow because
the boat will then end up sideways to the wind and the pull on the
anchor jerks sideways with extra force. I often wonder how many anchors
get broken out that would have otherwise stayed put if only the diesel
was kept turned off.

This is but one example of deviant behavior engaged in by diesel boats.
In general diesels make sailors incompetent. The best sailor in the
world is a man who has no motor whatsoever on board.

Wilbur Hubbard

Wilbur Hubbard wrote:

"Gordon" wrote in message
...
My neighbor, the fuel polisher, will tell you that you won't know
you have a developing problem until you hit some rough seas and stir
up the crap in the bottom of your tank.
Of course, then it's too late and at the worst time.
Gordon

Motor boat talk!

If the seas are rough it means there's wind. If there's wind you use
your sails and not your motor. I can always tell who the pretenders are
by their knowing that rough seas cause diesel problems because there's a
blender at work mixing all the crud at the bottom of the tank with the
fuel.

I've also noticed that diesel boat people have this motor = security
blanket syndrome. You see them, even at anchor, when the wind pipes up
on goes their motor. I think they have this idea they can motor forward
to reduce the tension on the rode. But, boy oh boy, why not just get
ground tackle you can depend on? Running the motor and taking it in and
out of gear might be the worst thing you can do during a blow because
the boat will then end up sideways to the wind and the pull on the
anchor jerks sideways with extra force. I often wonder how many anchors
get broken out that would have otherwise stayed put if only the diesel
was kept turned off.

This is but one example of deviant behavior engaged in by diesel boats.
In general diesels make sailors incompetent. The best sailor in the
world is a man who has no motor whatsoever on board.

Wilbur Hubbard
What auxiliaries do you have in your Swan 68 and Allied 32 footer? Just
curious.
--AG

That's true and fairly well known but it's a different problem.

Considering how promptly stuff started showing up in my filter bowl after I
started puting in StarTron, I think it must be doing a pretty good job of
moving the stuff into suspension and into the fuel intake. This is also a
sailboat the routinely heels 15 - 20 degrees so the tank gets pretty well
mixed. Thge slow build up from stuff moved into suspension is what I'm
concerned about tracking. You can't do much about the sudden clogs except
be ready to change filters in less than optimum conditions.

--
Roger Long

On Mon, 13 Aug 2007 11:52:23 -0400, "Roger Long"
wrote:

That's true and fairly well known but it's a different problem.

Considering how promptly stuff started showing up in my filter bowl after I
started puting in StarTron, I think it must be doing a pretty good job of
moving the stuff into suspension and into the fuel intake. This is also a
sailboat the routinely heels 15 - 20 degrees so the tank gets pretty well
mixed. Thge slow build up from stuff moved into suspension is what I'm
concerned about tracking. You can't do much about the sudden clogs except
be ready to change filters in less than optimum conditions.


A guy in Singapore who used four or five filters moving his new (to
him) boat about ten miles from Raffels marina to the Republic of
Singapore club spent several days washing out his tank and then added
some stuff called "soltron". I think it is the same stuff except sold
in the U.K. He got much the same effect, fine deposits in the filter
bowl. It lasted for some time, as I remember. He had vacuum gages on
his filters and said that the filters didn't seem to be clogging, just
this "stuff" in the filter bowls.


Bruce in Bangkok
(brucepaigeATgmailDOTcom)

That is consistent with what I'm seeing using StarTron (repackaged Soltron).
There is stuff that seems to be coating and sticking to the bottom of the
sediment bowl but the fuel in the top of the bowl is clear and the engine
runs fine at max RPM.

I pulled the filter yesterday and it looks good. I know this doesn't mean
much but there was no corresponding build up.

I went to the Racor dealer yesterday to buy a vacuum gauge but they were out
for the time being.

--
Roger Long