04/06/2015
 |
| Diesel Doos!! |
Not all
premium quality diesel hose is up to spec!! We discovered this in Opua shortly
before we left.
On Sheer
Tenacity we have a 300lt fuel tank on the port side, a 180lt tank on Starboard,
and a 60lt gravity feed day tank under the companionway. On deck we keep a
further 80lts in jerry jugs. We are admired and envied by many a cruiser! Why
so much???
The one
complaint that I read about, while building Sheer, was from those sailors
bemoaning their inadequate fuel capacities….. especially those cruisers who did
the NZ to Fiji run often! This 1160 mile
passage goes from 35 degs South, up to 17 South. The weather systems come through in
fairly regular waves, about every 7 days or so. The usual passage departs 1-2
days after the low front has passed through NZ, and the sea has calmed down a
bit, and the next high moves in bringing SE winds. This kick start only usually lasts for 2-3
days, before one gets stuck in the middle of the high with no wind. 2 days
later, the next low comes through and clobbers you. Added to that, is the
potential for the next low to meet up with another low emanating from the
tropics, to the north, or stalling on the back of the departing high, which can
produce a “squash zone”.
None of
these scenarios are too welcome! So one of the common strategies is to motor
north in the calms, and get the hell out of the risky zones……. Hence the diesel
tank capacity. Yeah, I know that 600lts is a bit of overkill…. Sheer could
motor for 1000 miles , or 11 days on that!
Now our whole diesel system relies on a
transfer pump and filter system, to move clean, filtered diesel from the
storage tanks to the day tank.
What happens
when the premium pipes start dissolving like overcooked macaroni? Well, when
the pump sucks, the pipes collapse, and diddly squat reaches the day tank!
Luckily, we picked up the problem in Opua, and replaced all the pipes….. except
for the little one that links the two halves of the port 300lt tank.
Now with all
our motor sailing, we were transferring diesel in 20lt amounts, from the 300 lt
port tank. After 150 lts, it indicated Nada… empty! Impossible! I put in 280 lts
just before we left! Oh hell, I reason, the little link pipe, which was
inaccessible, and therefore not changed, must have collapsed, trapping the
outer tanks 150 lts from draining into the inner tank!
So for the
last two top ups, I had to draw from the starboard storage tank. But now we had
to find some way to access the missing 150 lts.
But first I had to prove that my assessment was correct. So, we inserted
a little engine oil vacuum pump, with a long hose, down through the filler tube
into the bottom of the port outer tank…. And bingo , we find the missing 150
lts.
So, the
first task was to extract 40 lts, and transfer it back into the starboard tank,
so that it was full. We did that. Then we decided to check that the starboard
tank was in fact full….so lets draw more fuel, and fill the starboard tank to
the top!
After 20
extra litres have been transferred, we were worried! After another 80lts went
in we were panic struck! The tank had at least 160lts in it, from which we had
drawn 40… We should only have been able to fit max 40 lts to fill it up!
By this
stage, we are also pretty exhausted, have used a little engine oil pump, (which
sucks about 100ml per pump), to pump out 140lts of diesel.
Completely
discombobulated by the situation, we sat down and checked all our ullage
calculations over the past 4 years, searching in vain for some arithmetic
errors .
Then…….. the
possibility dawned, that for the past 5 years, could I have been mistaking the
port transfer position on the 3 way valve, for the Starboard one!
Was it
possible that the 150 lts that I believed was siphoned out of the port tank in
Brazil, by some little cretin…….. or that the 150 lts we believe had been
accidentally pumped into our bilges, when the transfer pump was not turned off
in the storm, and got pumped out by the automatic bilge pump into the sea…..
Surely it
was not possible, that with my advancing years, that my brain had turned to
porridge!
Well, the
truth must out! We did the tests, reversed the valve back to the previously
empty tank, and found it full! The empty tank had been the Starboard one, which
was now full again after hand pumping the 140 lts!!
Yes, Mary
says, a definite case of your brain turning to mush!
No, I argue,
with my advancing years, I have obviously discovered an unexpected , and
surprising re -emergence of my analytical skills, and if that was not the case
, how else could the problem have been solved ! I can now forgive you for not
turning off the transfer pump in the storm, as it now appears that you did not
cause 150lts of diesel to be pumped overboard! There now…. Doesn’t that make
you feel better?
No comments:
Post a Comment