T&T: 2 10 30 Micron Filters??

[Phil de l'Etoile]

Well as always things aren't usually as simple as we would like.

First of all, last year I discovered that I had lots of residue in the bottom
of at least 2 of my 4 60 gallon, rather shallow, fuel tanks (11-12" high
inboard, 4" high outboard).  I was able to empty one tank at a time, shovel
the "gunk" out of the lowest inboard part of each tank through the 14" top
access plate.  I then ran the old, seemingly "clean", fuel through several
paper-towel filtered transfers before returning it to each tank.

Knowing the this was only a marginally effective process, I closely monitored
my dual Racors with the 2 micron elements.  I sometimes would change filter
elements within a 4-8 hr period.

I always was aware that the vacuum gage was usually sitting up at the first
mark on the gage, so this new explanation now comes as no great surprise.  I
always changed elements if, or before, the gage got to the second mark, and I
have continued to use & refill just one of the 4, 60 gallons tanks in an
effort to purge the unclean fuel one tank at a time.  I just didn't know if
the vacuum gage was indicating still dirty fuel or too fine a filter (or
both).

Meanwhile, although the engine seemingly ran smoothly, I began to experience
overheating.  The Cummins dealer that first seviced the engine in November,
replaced the very dirty injectors, adjusted the valves, had the heat exchanger
rodded out, cleaned & pressure tested the exhaust manifold and transmission
cooler, and replaced the thermostat, the coolant, & several hoses.

Meanwhile I cleaned out the sea water strainer, replaced the apparently
undamaged raw water pump impeller & the scarred wear plate, replaced the
engine circulation pump, pressure-tested the cooling system, & replaced the
coolant cap.

Addiionally, the dealer had sent the turbo out for a rebuild, & had replaced
the air filter on the turbo.

After all of that, the engine still overheated, but now I was also unable to
attain the WOT rpm of 2800.  Because we had run through some mud (unlike the
PNW, 30' around here is "Deep Water") I had the boat hauled & had the prop
tested at the Prop Scan shop that I use, and found it to be no different than
it was after it had been serviced a year ago.

I then decided to go directly to Cummins West, the distributor in this area,
and that mechanic found that the engine temp was really 1850 not the 2100
shown on the temp gage.  He concluded that either my temp gage and/or the
sender were faulty, and that my sender was incorrectly located on the engine.

I will now remove, test, & move the sensor and replace it and the gage if
necessary.

Most importantly however, was that the tested boost on the turbo was only
showing 7 psi rather than 20+ psi.  This indicates that it is likely that the
rebuilt turbo (that was sent back to Kansas by the now somewhat troublesome
first mechanic) is faulty.

So the overheating seems nearly resolved, but the inability to reach 2800 is
not only new, but I am now facing a confluct with the yard that that handled
the turbo re-build, and that relationship is already strained.

How the 2 micron elements might have impacted all of this is hard for me to
say, but I'll be interested to see if the vacuum gage drops with the use of 10
micron filters.

So that's the story (to date).

Next week I deal with the turbo issue, but in the meantime I have ordered a
case of 10 micron filter elements.

Phil de l'Etoile
West Sacramento, CA

-----Original Message-----
From: LA Licata <lalicata at alum.rpi.edu>
Sent: Monday, December 31, 2007 01:59
To: Phil de l'Etoile <pdeli3 at gmail.com>
Cc: TrawlerList TrawlerList <trawlers-and-trawlering at lists.samurai.com>
Subject: Re: T&T: 2 10 30 Micron Filters??

Phil.

How long have you had your engine?

Have you had any fuel problems that otherwise might be explained by
fuel starvation?

If you can run at WOT at the correct rpm for a while without any
problems, and you can run your "unloaded at the dock test" also
without any problems, then while on theory, he may be right, I think
you can be comfortable with the setup you have because it is working
for you.

The 30 vs 10 vs 2 micron argument has been hashed on this list many
times. My personal opinion, mind you, very personal, is that if what
I have is working for me, than there are plenty of other things not
working that need my attention...

Lee