Tom Martin
Well Known Member
I have some concerns about the stock RV14 fuel system and I am looking for some suggestions. The following pic is from the assembly plans
As can be seen in the picture the fuel flows through the valve , through the filter and pump on the way to the firewall. A drop dead simple fuel system.
This is the good news.
The problem I have is that there is no way to sump that filter, or to know if it is getting full of debris.
We have two independent tanks and it seems a shame to not be able to switch tanks if the filter were to plug.
A filter for each tank would be preferable. Yes there are a lot of single point failures on an airplane but why design one in for the cost of an extra filter?
To clean the filter means that you have to "break into" the fuel system. By that I mean that during servicing the fuel line will have to be removed from the back of the filter. This one action opens the door for leaks or foreign mater to get into the system. I do not think that fuel lines were meant to be opened and closed on an regular basis: over time what does this do to the flare? A simple gascolator is designed to come apart for cleaning without removing fuel lines.
The location of the filter is going to be a bit of a bear to get at under the panel. When service items are not easy to service the natural tendency is to "do it later"
I know that no one here is guilty of that but fuel system problems are the number one cause of engine failures.
In Canada we are required to use a gascolator but I really like the idea of a filter before the fuel pump and the stainless steel tunnel precludes putting a gascolator in that area. A filter, or gascolator in each wing root is an option but that adds a lot of complexity and again makes the system difficult to service, which is not desirable.
Has any one thought of an alternate system?
As can be seen in the picture the fuel flows through the valve , through the filter and pump on the way to the firewall. A drop dead simple fuel system.
This is the good news.
The problem I have is that there is no way to sump that filter, or to know if it is getting full of debris.
We have two independent tanks and it seems a shame to not be able to switch tanks if the filter were to plug.
A filter for each tank would be preferable. Yes there are a lot of single point failures on an airplane but why design one in for the cost of an extra filter?
To clean the filter means that you have to "break into" the fuel system. By that I mean that during servicing the fuel line will have to be removed from the back of the filter. This one action opens the door for leaks or foreign mater to get into the system. I do not think that fuel lines were meant to be opened and closed on an regular basis: over time what does this do to the flare? A simple gascolator is designed to come apart for cleaning without removing fuel lines.
The location of the filter is going to be a bit of a bear to get at under the panel. When service items are not easy to service the natural tendency is to "do it later"
I know that no one here is guilty of that but fuel system problems are the number one cause of engine failures.
In Canada we are required to use a gascolator but I really like the idea of a filter before the fuel pump and the stainless steel tunnel precludes putting a gascolator in that area. A filter, or gascolator in each wing root is an option but that adds a lot of complexity and again makes the system difficult to service, which is not desirable.
Has any one thought of an alternate system?
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