Because biodiesel and related fuels are more viscous than ordinary diesel, it tends to pick up dirt from the bottom of the fuel tank. For this reason, I have been advised to fit an ancillary fuel filter with a transparent casing before the main filter so that dirt can be seen before it builds up too much.
However, I am having difficulty in fitting the filter. When I have fitted it to the fuel tank end of the fuel line, I suck on it to fill the filter with fuel and then attach it to the engine side of the fuel line.
But when I suck on the filter, it is difficult to get all the air out and then when I attach the filter to the engine side of the fuel line, a lot of air always gets in so that, in the end, the ancillary filter is half full of air.
Can anyone explain how to avoid these problems? There must be a bullet-proof technique for fitting the ancillary filter without getting air into the filter and into the fuel line.
Many thanks,
Gerry