Andair vs. Stock Airflow Fuel System

[FlyHigh]

There may be another thread on this somewhere, but, I have yet to find it.
I am going to install the Andair Duplex fuel valve as I need return fuel from my injected engine.
What are the Pro's & Con's, other than the sheer costs, of installing a full Andair fuel system over the Airflow ? I know that Andair had early issues with their fuel pumps. Also, Andair recommends 2 fuel filters (their gascolators) before the fuel pump. These gascolators will need to be serviced, so, where do you mount them.
Any input or direction would be appreciated. Thanks

 

[penguin]

IMHO Andair stuff is great and better than anything else available.

Andair suggest a gascolator is mounted in each wing root in the tank outlet line before it passes into the fuselage. This is the best place for maintenance and means there is no fuel spilt in the fuselage when cleaning the filter(s). There is no problem with using one in-line filter in the fuselage, it is more difficult to get at and will result in a fuel spill in the cabin when removing.

BTW if you have a standard injection system look carefully at the need for a fuel return line & duplex valve.

 

[TS Flightlines]

Jeff----the Airflow Performance pump and the Andair 375 pump are not used with a full return. SDS and EFii have their own pumps for their systems.

Tom

 

[planenutz]

If I understand your question correctly, you're installing a fuel injection system on your RV-8 so I'm assuming you're talking a typical 4-cylinder Lycoming of some kind. You also mention Airflow Performance, so assume you're talking their fuel injection system and the typical Purge Valve they supply?

As Penguin suggests, you do not need a duplex valve for this system. I found it much easier, and much cheaper, to simply run a return line to a tank and let the warm fuel mix with the cold fuel back in the tank. You could run that line parallel with the breather line using aluminium tube and a couple of standard AN fittings.

Andair do make very nice fuel system components but they're not the only ones to do so... and of course Andair would recommend you to buy two gascolators... they can sell more this way (and they're not cheap). As discussed elsewhere, the Aerolab Filter is a great option and the long term maintenance of the filter is easier as it doesn't require the removal of the intersection fairlings. And you only need one of them. As the filter removal is external to the fuselage no fuel is spilt inside and best of all you don't have to get into the cockpit and be head down, *** up smelling fumes. I also like the fact that in a typical installation it pretty much ends up being at the lowest point of the entire fuel system and therefore is the best place to have a sump drain.

Hope that helps with the options.

 

[rv8ch]

I have the Andair duplex valve since I originally planned to install a FI system that required it, but changed to Airflow. Doing it again, I would only install a "simplex" with the purge valve just going to one tank. Or skip the purge valve.

I think the Andair fuel filter is too small - at least it feels small to me compared to others like the Aeromotive.

I would also consider the Aerolab filter system in each wing root - it seems to make sense to make it easy to check and clean your fuel filters. The way I did mine it's "easy" but no where near as easy as the Aerolab system. I'd retrofit it, but I'm lazy, and I like to fly!

 

[DanH]

I am going to install the Andair Duplex fuel valve as I need return fuel from my injected engine

Constant flow (Bendix, Precision, Airflow Performance or AvStar), or electronic (SDS or EFII)?

 

[FlyHigh]

Andair

Many THANKS TO ALL for your input. I now know that I need to re-think things as I am finding out that there are many options available. I guess that I am too used to the commercial general aviation. high dollar names i.e. Weldon & Dukes. I am learning the experimental products and will have many questions at OSH.

 

[TS Flightlines]

Jeff----as a suggestion, decide how complex you want the system. The stock mechanical style systems are pretty simple---supply and discharge, single lines, no returns. Maybe a purge line, but not required.
The electronic systems are more complex, supply and returns for both sides, computer controlled, duplex selector valve, etc, and thats just the cabin side.

In an RV8, a duplex system will take alot of thought and planning, as there isnt alot of space for plumbing. BUT, YES---it can be done. Only real requirements I know of versus a stock type system is alot of patience, pre-planning, and understanding how the system will interface with others.

Tom