Fuel Tank; Filling The Tank; Phase Separation; Fuel Filter - Ockelbo B21 CAB Owner's Manual

4.1.1 Fuel tank

The boat is equipped with an aluminium fuel tank with a capacity of 160 litres. As a
precaution, all the capacity may not be useable due to trim and loading conditions, so
consider keeping at a minimum 20% of reserve fuel in the tank.
Fuel tanks with levels less than 20% capacity can cause engine stalling problems due to
fuel starvation or by allowing sediment and dirt to enter the fuel supply lines. Keep the
tank full and monitor the fuel level often to prevent this from happening.

4.1.2 Filling the tank

Ensure that the right type of fuel is selected (check engine manual). When filling the tank,
do not attempt to top off the tank. When the nozzle shuts off, the tank is full, and
continuing to fill past the fuel fill shut-off causes the system to spit back fuel.
Before fuelling, carefully read the chapter on Fire Prevention in this manual!

4.1.3 Phase separation

Humidity and condensation may create water in your fuel tank which can adversely affect
the function, with ethanol blended fuel. A condition called phase separation can occur if
water is drawn into the fuel beyond the saturation point. The presence for water in the
fuel beyond the saturation level separates most of the ethanol in the fuel from the bulk
fuel and drop to the bottom of the tank, significantly reducing the level of ethanol in the
fuel mixture in the upper level (phase). If the lower level (phase), consisting of water and
ethanol, is deep enough to reach the fuel inlet, it could be pumped directly into the
engine(s) and cause significant problems. Engine problems can also result from the
reduced ethanol/fuel mixture left in the upper phase of the tank, or just from the water
contamination.
If phase separation does occur, your only remedy is to drain the fuel, clean and dry the
tank completely and refill with a fresh, clean tank of fuel. Also, clean or replace fuel filters
(see chapter 4.1.4)
The best method to avoid these problems is to avoid water from accumulating in the
tank. Try to maintain a high fuel level in the tank, in particular when the boat is not in
use for longer periods. This reduces the air flow in and out of the tank due to changes in
temperature as well as limiting fuel exposure to humidity and condensation.

4.1.4 Fuel filter

As a part of the fuel system, a fuel filter is installed in-between the tank and the engine.
There is always an external filter mounted in the boat. See chapter 7, figure 1.
Maintenance of the fuel filter is essential to secure a reliable operation. For some
engines, the filter can also be connected to the instrumentation and provide a warning if
it needs maintenance. Please check the instructions provided by the dealer who installed
the engine.
4. SYSTEMS & COMPONENTS__PAGE 36