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Subject: TWL: Firsts - Installing Primary Filters
From: Garrett Lambert (e16@XXX.XXX)
Date: Sun Apr 01 2001 - 18:57:53 EDT
When I bought my boat last June, the surveyor strongly recommended replacing
the original Fram water separation filters which have no sight glasses and
are literally inaccessible.
Because their location would change, the job involves more than simply
screwing the fittings out of the old and into the new. Although on the scale
of boating projects this changeover is simple, it has to be done right.
Installing two new filter units produces 16 new joints, each of which has to
be perfect. Absolutely no leaks of fuel or air - especially air. Hiring an
"expert" wouldn't have been particularly expensive, but not having even
changed a filter element until now, I wanted to do it myself as a learning
exercise.
So I procrastinated until last week.
Here's the drill:
First question: What units to buy? Many TWL members extol Gulf Coast's paper
towel filters, especially for fuel polishing systems, so I phoned the
company. I'm sure the GC's must be worth the price for heavy duty
applications, but I decided to buy Racor. Okay, but which model, and with or
without priming pump? Chose the slightly more expensive 500 FG without pump
partly because it's very popular in this area - not necessarily a good
reason - but mostly because of its higher capacity, very much bigger sight
bowl, and inexpensive filter elements that are particularly easy to change.
(The pump option becomes momentarily attractive a little later in this
saga.)
Second question: What piping to use? According to the dealer, two options
meet code: 3/8" gas copper pipe with double flared fittings, or 3/8" id
(3/4" od) reinforced rubber fuel lines on barbed fittings with either SS
hose clamps or crimped fittings.
Considerations: rubber would make the transitions very much easier, and
avoid the need to cut and re-flare the existing lines. However, copper would
halve the possibilities for leaks since each copper connection would produce
only one interface, whereas each rubber to barb to mating fitting produces
two. A good flaring kit is inexpensive, and the dealer was even willing to
lend me one for a few days. Copper, please.
However, he then discovered he had Racor barbed fittings in stock, but no
flared fittings, and a phone call to his distributor produced the same
result. I could wait for the flare fittings, but I'm primed and ready, so
make it hose. Will that be SS clamps or crimped? Could do the former in
situ, but crimped would require bringing the hoses and fittings back to the
dealer. SS clamps, please. Can always revert to crimped if necessary.
All-equipped, board the boat on a very windy, rainy day. With an electric
heater on low, the engine room temperature is comfortable. The built-in 12v
lighting is surprisingly effective, but a 120v extension lamp illuminates
the corners and the depths. However, space is tight, and I'm not quite so
flexible as I once was. The advantages of a single engine installation are
immediately (and painfully) apparent.
1) Close the gate valves from the tanks and remove the port Fram while
avoiding spills. Using two wrenches to release 20 year-old connections while
in a semi-fetal position is awkward, but no worse than being under a sports
car. A stack of ultra heavy duty paper wipes takes care of the small
dribbles while a large coffee can holds the still full filter unit upright
for removal from the boat. I do this immediately in view of my long history
of knocking things over.
2) Teflon - see note below - and screw the Racor O-ring-hose fittings into
the 500 FG.
3) Attach the Racor to the bulkhead. Hmmmm. A template is provided so it's
easy enough to put the screws in the right location - make sure they're
level - but once the filter is dropped down onto them, it's almost
impossible to get at the screws to tighten them. Poor design. Removing the
fittings would help, but putting them back in situ would be almost as
awkward as removing the Frams. Finally use a wrench on one of the stubby
inserts from a multi-bit screwdriver to drive the screws fully home. Hex
headed screws would have made everything easy.
4) Tape and thread fitting into output side of fuel-line gate valve. Whoops.
Not the same size as all the others. Round trip to dealer for correct part,
and install. Slip hose over barb, lead hose to Racor ensuring no crimping at
bend, mark, remove, cut to length, slip on 2 clamps, install and tighten.
Satisfyingly easy. Same procedure from the Racor output to the engine line.
Clamp hoses to bulkhead.
Sit back and admire tidy installation. Hose simplified everything.
5) Squirm over and repeat steps 1-4 on starboard side. (Remind self of
manoeuvring convenience of twin engines...).
6) Re-prime the system: Open the bleed screw on the port Racor and open the
gate valve from the tank. Nothing happens. The Frams were installed so low
the tanks filled them by gravity. The higher Racors would fill the same way
if my tanks were full, but they aren't. Should I have bought the pump
models? Nah. The diesel course teacher said the finger lever on the engine
lift pumps will draw fuel through to the bleed screws on the injector pumps.
Have to use it anyway, since I undoubtedly let some air in downstream of the
Racors. But to save finger, first fill the voluminous Racors with clean
diesel from a container. Small problem: I don't have any, and the weather is
too foul to trudge over to the fuel dock. Tomorrow's another day, and as it
is, I'm going to wake up in the morning feeling a lot of muscles I hadn't
thought about for a while.
Silver lining in every little cloud. On the way home realize that in my
enthusiasm, I forgot about changing the secondary elements. Would have had
to re-prime all over again. Am also going to the diesel course that night
for a lesson on the fuel system. (It included hands-on practice in priming a
Perkins which had been run completely dry, and I felt a lot more comfortable
about doing my own engines the next day. Sometimes lucky is better than
smart.) Fellow student said he'd just re-installed his Yanmar in his
sailboat that afternoon. Started engine and immediately heard shouts from
friend to "Shut it off! Shut it off!" He'd filled the sump but forgotten to
screw in the oil filter. Oil everywhere, and a day or two will be required
to clean it up. Practical lesson: take time to check, re-check, and
re-re-check. Everything.
Day 2: back to the marina with a new jerry can and a small garden pitcher,
buy 2 gallons of diesel, and board the boat. Change the secondary filter
elements on the port engine since they're the easiest to get at. Each pair
of filters consists of a double cover mounted permanently to the engine with
centre bolts through 2 canister filters to 2 separate bottom "holders". Try
to be careful, but diesel spills everywhere including on me. (Later realized
I should have opened the bleed screws on each top and then used the drains
at each bottom to empty each one into a can. Next time. Meanwhile, the
bilges are now a lot cleaner.) Each of the 4 units requires 4 new O-rings -
under the bolt head; on the centre post that slips into the filter element;
and on the top and bottom covers - and these are included in the filter
package. If you don't drop them into the bilges, re-assembly is easy. Fill
the Racor. Dead simple with the removable top. Fill the secondaries:
pain-in-the-*** with the itty-bitty fill holes, even with the little
pitcher. More diesel over the engines and me. After wiping them down,
they're even cleaner and shinier than the bilges. I'm just dirty and stink.
Next time I'll also bring a small kitchen funnel.
Now purge air from the system. Open the aft bleed screw on the injector
pump. Why the aft screw? Well you might ask. Start to pump the little lever
on the lift pump. And pump and pump and pump. Air bubbles finally appear,
and eventually nothing but clean fuel. Hurrah. Theory into practice. Close
the bleed screw, climb up to the helm, crank the engine. And crank and crank
and crank, with pauses to cool the starting motor. Nothing. Obviously
there's still some air in there somewhere. Please let it not be a leaking
joint. How would I determine which one? (Answer: pressurize the system with
a pump.)
By now, I'm kind of fed up, and the notion of calling in that "expert"
tickles at my increasingly humble mind. Remind self of people who give up
just before they're about to win. Eureka! Notice that the engines do not sit
perfectly level, and that the injector pump's forward(!) bleed screw thus
sits just a fraction higher than the aft one. Crack it, and a great whoosh
of highly pressurized air blasts out - that little finger lever really
works! A few more finger strokes produce clean fuel. Quickly close off the
bleed screw, up to the helm, crank again, and almost immediately hear the
welcome sound of a Lehman happily purring at idle.
Full of re-born confidence, repeat all of the above on the starboard engine
while lying along the fuel tank, and fire it up on first try. Bliss.
Just to be sure there are no leaks, I run each engine up to operating
temperature, then shut down and go to lunch in the marina cafe. Come back an
hour later, and both engines start immediately. Quietly savour brief moment
of triumph.
As I open the door to the house from the garage, my wife takes one whiff and
says "Stop and strip right there." It being the "Essence de Diesel", I
somehow know that she doesn't have romance in mind.
Some additional comments:
Note on taping joints: if using Teflon tape only the yellow variety meets
code. The white stuff is certified only for water and air, not for fuel.
Ensure no tape extends beyond the threads to avoid the possibility of
contamination from a piece that could break off. I was informed after the
fact that only pipe fittings should be taped, not flared fittings. In my
zeal I did both, but because I was paranoid about not letting the tape
extend beyond the thread ends, I avoided having a bit of tape between the
flared surfaces. That would have certainly produced the dreaded leak.
A little experience is a wonderful thing. The port side, though it has the
easiest access, probably took me a total of 5 hours or more. Most of it was
a combination of worrying my way through each step and doing all that
re-checking, and running back and forth for bits & pieces. With correct
parts and much confidence, the somewhat more awkward starboard side probably
took less than an hour total. The next filter changes will be a piece of
cake. Just as useful, a couple of days' crawling around the engine room also
taught me a lot about the boat's subsidiary systems that otherwise lurk
there unnoticed.
One of the fringe benefits(???) was the discovery of the source of water
that I sometimes see collecting in the boxes under the engines. With the
engines running, both Jabsco raw water pumps leak at the cover plates. I
hope it's just that the gaskets were forgotten in the previous impeller
changes. Impellers are, in any event, the next maintenance job on my list,
and tonight's diesel lesson is on the cooling system. Talk about great
coincidence a second time! (During the hands-on session, we drained a
Perkins, and among other minor tasks, removed a Jabsco cover plate and
pulled out and replaced the impeller. As a bonus, we also learned how to
make perfectly matched new gaskets using a small ball peen hammer and a
sheet of gasket paper, so servicing my own pumps on the week-end will be a
lot easier.)
I also found that despite the close quarters, with a roll of old carpet to
lie on, everything is accessible and reasonably comfortable, and working on
the bulkhead side is not at all the problem I thought it would be. Lots more
to learn, but a lot less trepidation about the next jobs. I'm really glad I
did it myself rather than hiring someone.
Finally, you will have noticed the remarkable relevance of the community
college diesel course to my specific needs. It's only 8 sessions of 3 hours
each, but 2/3 is in the shop. It's improbable to think that yours could be
quite so well-tuned to your needs, but it's a terrific program, and I
recommend strongly that every first-time trawler buyer look for one like it.
Now to hook up the holding tank so I can participate in Trawlerfest at
Poulsbo in June. And switch to Eau de Toilette.
Cheers, Garrett
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