Regal 53 SC Owner's Manual page 56

SOLUTIONS FOR RECOVERING DIE-
SEL FUEL QUALITY
As a Regal yacht owner you have a huge investment in
your diesel propulsion system. Being the engines are key
components in the system, keeping the fuel system clean
is a high priority.
Following are some solutions to help clean up a diesel
fuel "algae" problem:
Periodically use a biocide to control microbial activity
which can lead to more rapid formation or clustering of
solids such as wax and asphalt. Remember that biocides
do not prevent microbes from forming but aid in break-
ing up the clusters. If the vessel is to be stored for over 2
months pour biocide in the semi empty vessel fuel tank.
Fill the fuel tank with fresh diesel fuel to prevent conden-
sation build up. Run the boat for a short run to better mix
the biocide inside the fuel tank and fuel system before
storing the vessel.
1. Always make sure the fuel tank fi ll cap is securely
tightened to prevent any water infusion.
2. Always buy diesel fuel from a marina or fuel dock that
moves a large amount of fuel through the pumps.
Ask how often the fuel dock pump fi lters are changed
and if their diesel fuel is blended with a biocide. Al-
ways carry a couple of extra primary and secondary
diesel fuel fi lters. Use exact replacements in order to
match micron fi ltering capacity.
3. Figure on changing both primary and secondary fuel
system fi lters more often due to today's diesel fuel
shorter storage life.
4. Make sure to drain the 10 micron Racor water separa-
tor fuel fi lter and the engine secondary fuel fi lter be-
fore each outing. Look for sludge/water. Dispose of
contaminated diesel fuel properly in approved con-
tainers. Do not drain diesel fuel in the bilge.
5. Never let diesel fuel remain in the boat's fuel tank
for more than six months. The cetane valve will drop
which is its ability to ignite easily. Good grades of
diesel support a cetane rating around 50. When the
cetane level drops the engine is more diffi cult to start.
The combustion process moves from a controlled
burn to an explosion. Pump out the old diesel fuel
and replace with a fresh supply.
Old diesel fuel creates more stress on engine parts and
produces more noise than normal resulting in the trade-
mark diesel clatter.
Pour a cetane booster and conditioner in the fuel tank-
with the new batch of diesel fuel.
Note: In severe cases of "algae" the fuel tank may need
to be pumped out. To remove the ability to generate the
tank should be pressure washed which removes small
deposits of "algae" from the baffl e system and hard to
reach areas. Add a biocide (not a conditioner) and then
top off the tank.
Remember: LESS AIR MEANS LESS WATER AND
LESS GROWTH!
4
Chapter 4