This blog post was first published on
Three Sheets Northwest, on online boating magazine local to the Pacific
Northwest , in February of 2015. The original article can be
read here.
We were motoring up Fitz Hugh Sound along the Central
Coast making our way to Ocean Falls on
June when the engine started hunting, fluctuating 150 RPM from where it was
set. It’s always a concern when there’s something going on with the motor, but
the symptoms were consistent with a dirty fuel filter – something David was
planning to change out once we got there – so he eased the throttle back a bit,
which seemed to help. The next day he replaced the old fuel filter; and when we
left Ocean Falls
Fast-forward
to October and issues with our diesel-powered hydronic heating system: We had started getting flame-outs about 12 months
beforehand, which coincided perfectly with a dying house battery bank. Ever
the optimist in search of the easiest solution, I thought the problem resulted
from low voltage and would resolve itself once we replaced the batteries. David
(the mechanical engineer and practical one) wasn’t convinced, so he changed out
the fuel pump along with the filters and we were back in business . . . for a
while. But there we were, months later, plagued with flame-outs; it was starting
to look like we’d picked up some bad fuel along the way.
To check, David disconnected the fuel lines (supply and
return) to the heater’s boiler and installed temporary lines that he ran from a
jerry can that contained fresh, clean diesel. The system tested
well: The hydronic loop heated up quickly and the cabin fans went online
in less than 10 minutes (a big improvement over recent start-up times).
Similarly, the domestic water Aquastat was quickly satisfied – all with
no flame-outs.
Our questions had finally been answered: We had “The Bug”.
Getting
Rid of the Gunk
Our
fuel system is set up so that diesel can be drawn from all three tanks
(starboard side, port side and forward) simultaneously. The fuel is then run
through the engine’s filtering system before it flows to the engine and the
excess is fed back to the port side tank. Because the fuel in this tank had
already been technically “polished”, we were confident it was clean . . . or at
least the cleanest. The forward tank sits higher than the other two and feeds directly
into the starboard side. This tank was already empty, so we knew the only fuel
we had to remove was on the starboard side.
First,
David built a pump system to empty the remaining fuel from the starboard tank. From Cambria ’s log:
The fuel transfer rig consisted of a piece of
3/8-inch OD Type copper tubing about 6-feet long to be able to reach all the
way to the tank bottom; two pieces of matching-sized clear hose, one connected
to the pump intake, and the other as discharge into the buckets; and a 12-volt
Facet Cube fuel pump (a spare for our Hurricane Heater).
When I set up the fuel transfer/polishing
"rig" I was in two minds about installing a bank of filters (10-5-2 micron) ahead of the pump, and finally decided
that would have cost more than the value of the fuel I was trying to clean.
Instead I elected to pump the fuel directly out into buckets in order to really
see what was living in the tank. Then, depending on its condition, either
return it to the tank via Baja filter, attempt to "polish" it
chemically and return it filtered to the tank, or discard it entirely.
With
the transfer rig in place, we started to remove the diesel from the starboard
tank and placed it in clean white buckets. Initially, the fuel coming through
the lines was clean with no obvious signs of contamination – approximately
eight gallons or so. Once we started to see particles in the fuel, we stopped
pumping. David then treated the “clean” fuel with a shock dose of Bio-Kleen
biocide and transferred it to the port side tank, filtering it through the Baja
filter as he did.
We
continued to remove the rest of the fuel from the tank:
The remaining seven gallons of diesel were obviously contaminated – black
particles, held in suspension ranging in density and size from negligible to
significant, trace “smudges” to small pieces, yet still large enough to clog
the fuel pump periodically during the transfer operation. The amount of contaminant drawn from the tank also varied
as the suction tube was moved around within the tank. As the fuel passed
through the pump, the algae/growth particles were broken down and blended into
the fuel.
Very surprisingly, I chemically treated the
"molasses" fuel and allowed it to stand overnight. By mid-next day,
there was a heavy black sediment in the bottom of the buckets and the fuel was perfectly
clear and ready to be filtered back into the tank. From a total of 12 -15
gallons drawn from the contaminated tank, the quantity of fuel unable to be
re-used amounted to less than a half gallon.
With
as much of the sludge removed from the tank as we could manage, we then filled all
three tanks to 100% with fresh diesel and treated them with the following
products from Power Services:
- Bio-Kleen
Diesel Treatment (kills microbes in diesel fuel): a shock dosage for all three
tanks.
- Clear
Diesel Treatment (removes water and contaminates from diesel fuel): a
maintenance dosage for the port and starboard tanks.
- Diesel Kleen With Cetane Boost (injector cleaner): a shock dosage to all three tanks.
How Much
Did We Save?
Out
of curiosity, David contacted an all-service fuel company in Everett
Here’s what we actually
spent:
Copper Pipe: $10
Clear Hoses and Fittings: $10
Diesel Treatment: $70
Fuel Pump: $0
(we used a spare; a new one costs $40)
Total: $90 (and
an afternoon’s work)
It’s been over a year since we polished the fuel and, so far, the heater has been performing very well. We did start to experience occasional flame-outs again after a couple of weeks but the problem was resolved by cleaning the deposits from the burner nozzle on the boiler. The engine is also running well, but there’s likely some debris sitting at the bottom of the tanks that we weren’t able to reach. The biocide, however, would have killed the algae and kept it from growing further.
8 comments
Very useful article. Something we may need to do to our diesel. Although, I'm not sure if we can do it ourselves at our marina or if we're required to use an external contracts.
ReplyDeleteHonestly, I was surprised at how easy the process was and how well it went. I give the fact that we were down to our last 15 gallons (give or take) s lot of the credit.
DeleteCheers!
We knew we wanted to polish our diesel before leaving the docks, but I was scared at how long it would take and how much of a pain it would be. We actually did it after work one evening - it probably took about an hour and a half for two tanks (two engines) - and we could leave the docks knowing our engines wouldn't be silly on account of contaminated fuel. -Lucy
DeleteSo wonderful to have a handyman onboard. We lucked out on Irie and never had to clean our diesel tank. From the moment we owned our boat, we always and ever used a Baja filter before the diesel reached the tank. That patience and persistence might have paid off. :-)
ReplyDeleteThe silly thing is we have a filter aboard as well but haven't used it much because the diesel here is so safe but we were in a somewhat remote area where they probably didn't sell enough fuel to keep their tanks fresh. It's not a mistake we'll make again! But at least we were able to take care of the problem ourselves.
DeleteAbsolutely fascinating! I never knew diesel could be cleaned or that it needed to be :)
ReplyDeleteMars xx
@TrollbeadBlog from
Curling Stones for Lego People
We've been really lucky and have only caught the "bug" once in 15 years so it was our first time having to clean it. Now that we know how easy it is, we'll never pay for the service!
DeleteThe picture of the three Power Services products could have been taken on my boat. Great products. I started using them a few years ago at the suggestion of an old timer who serviced my injectors. Have not had an issue and suggest these to other folks as well.
ReplyDeleteMy aluminum tanks are coming out this year. One has a leak and I want to steam clean and add clean outs to both. Just in case.
Have fun!