T&T: T&T Electric Fuel Pumps

[Albin43SDtr]

'Lo All,

Re: Priming a Racor 1000 by pulling fuel through it.

I have 3 Racor 1000s on the Celestial. The fuel polisher uses one. I 
have a Walbro pump installed so it pulls fuel through the filter.

The fuel polisher pump will "prime" the polisher's filter only up to 
the height of the fuel outlet fitting, which is slightly more than 
half way up the filter. There is essentially an air chamber from 
which the air cannot be removed by the pump above the outlet fitting. 
This means that only part/half of the filter media is being used to 
filter fuel, if the pump is the only means of "priming" the filter. 
Of course, all the air in the filter that is displaced by fuel is put 
into the fuel lines. I do not know if the remaining air would be 
removed over time as the filter clogged in the lower area. When 
clean, the filter media is only partially used, unless the canister 
is completely filled with fuel. (I had LOTS of experience with this 
when installing the system as {I found later} the stems on the new 
valves leaked air until I replaced them. The saga is in the archives.)

The Celestial is set up so I can cause the polished fuel to flow into 
the bottom crossover line, so putting air into that line would be no 
problem. I am very careful not to put air into the main fuel 
manifold, unless I plan on carefully purging it. (The system can also 
pull fuel from the bottom crossover line, which is the normal source 
for the fuel polisher as the crossover lines are at the very bottom 
of the main tanks.)

The polisher filter is located quite low in the boat, so I can 
normally fill the filter by gravity from the main tanks. ONCE(!) when 
low on fuel, I used the pump to partially fill the filter, turned off 
the pump, loosened the lid (so air could displace the fuel) and 
drained the fuel in to a container. Then I replaced the lid, turned 
on the pump and again partially filled the filter, removed the lid 
and dumped the fuel from the container into the filter. What a hassle!

The fuel system in the Celestial is plumbed so that the fuel polisher 
pump can fully prime the filters on the main engines and generator. 
Last week, it took about 20 minutes to change the Racor 1000 filters 
and the on-engine filters. This discussion/thread reminded be that it 
was time. Thanks :) !

The point of all of this: Not all filters/installations are the same, 
so be sure to see how the ones you are using are made and installed - 
and deal with it accordingly. All too often, what is true - and 
stated here on T&T as fact - is true only for certain 
systems/manufacturers as experienced by the poster, but not 
necessarily universally true for all. If someone who is not really 
familiar with the peculiarities of boats reads some of the statements 
and accepts them as fact, it could get him/her into trouble, or at 
least, result in unsatisfactory performance. All of the posts are 
really a great and valuable cumulative guide and provides a baseline 
of experiences, which, when properly applied, filtered and adapted, 
can provide great insight and general guidance, but seldom provides 
categorical, irrefutable guidance.

JMHO, Caveat Emptor and all such disclaimers!


Take care and be safe.

Wayne
M/V Celestial
Albin43 Sundeck