Gascolater location

[whittfic]

Hi Folks

This is my proposed set up for the electric fuel pump/gascolator on my RV6 project:

http://s456.photobucket.com/albums/qq282/whittfic/

My reasoning for doing it this way is as follows;

- Having heard of some instances of vapor lock occurring in the gascolator, I wanted to relocate it to a cooler area. I plan to access the drain valve through a hole cut in the wing root fairing.
- I wanted to keep the gascolator downstream of the fuel pump primarily so that if there was ever any leakage from the unit or connections I wouldn't end up with air being drawn into the fuel lines.
- Also decided to locate the fuel pump with associated connections (potential fuel leaks, fire etc) outside the cockpit. Kind of paranoid I guess but two less fuel connections in the cockpit makes me feel a little happier.

It all seems to fit in OK without interfering with anything. So a question for the wise and experienced, is there anything about this set up that could be cause for concern?

I am not in the habit of straying too far from the original plans so would like to be sure I have not missed something or am setting myself up for bad things to happen.

Clive Whittfield
Auckland
New Zealand
RV6 engine baffles

[andrew phillips]

I located the gascolator in the wing root too. I installed mine a bit lower so that the quick drain is directly accessible through the fairing. My only comment would be that it will be a real pain to work on that fuel pump if it ever need service.

[noelf]

From your photo:
Does this imply that you have 2 electric fuel pumps?

Do you also have a fuel tank selector valve? Inside the cockpit?

What happens if you turn on a (or both) boost pump and DO NOT have that tank selected as feeding fuel to the engine? It seems you will be pressurizing that side's fuel lines and it has no place to go. I have no idea what the boost pump will do in that situation (failure modes, etc).

On the positive side, I do like the way you were able to package this function in the given area.

[gasman]

The pump is 2 1/2" tall, the space there is 3" with wing on. And the fuel fitting from the wing is just about where the fuel pump is located. Maybe a little lower.

Looks like the fuel is to enter the cabin, go to the fuel valve, and then back out to the gascolator and fuel pump? If you are going to do this, and you make it fit, I would use a quality gascolator.

[frankh]

Originally Posted by noelf

From your photo:
Does this imply that you have 2 electric fuel pumps?

Do you also have a fuel tank selector valve? Inside the cockpit?

What happens if you turn on a (or both) boost pump and DO NOT have that tank selected as feeding fuel to the engine? It seems you will be pressurizing that side's fuel lines and it has no place to go. I have no idea what the boost pump will do in that situation (failure modes, etc).

On the positive side, I do like the way you were able to package this function in the given area.

This maybe a single pump solution (with a mechanical pump) but IF it is a twin pump setup that I would strongly recomend NOT having a selector valve.

You can check out my FI'd wingroot pump only system for ideas, I but the same thing for a carburetted airplane that worked great too, with not machanical pump in either case.

Frank

[s_tones]

Disclaimer: Non builder lurker guy.

I replaced my stock Piper gascolator which is similar in construction with a vastly superior one (Steve's Gascolator). I had a lot of problems with that bail wire setup and, although it is widely used, I think it's a terrible design for 2 reasons: First, the seat on the top portion is aluminum (in the Piper model anyway) and subject to warping and subsequent leaking because the bail wire exerts uneven pressure on the union of the mating surfaces. Second, the bail wire in the stock model is flimsy.

Steve

[whittfic]

Thanks for the replies. All good food for thought.
Just to clarify, the fuel line enters the cabin from a flop tube connection near the leading edge of the wing. You can see this connection just forward of the fuel tank bracket (I have a cover over that connection now by the way).
Fuel from both tanks goes to a selector mounted in the standard Vans location and then to this (single boost pump) set-up. From there it re-enters the cabin area and exits throught the firewall to a mechanical pump.
Engine is a carburetted Lyc 0360 A1A driving a Sensenich fixed pitch prop.
Did think about ease of servicing etc verses cooler gascolator location, and also the rather 'agricultural' look of the gascolator. Decided to give this one a try but any issues and out it goes!

Clive