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Black fuel hose in fuse

Has anyone used the black 3/8 ID fuel hose inside the fuselage, like from the tank selector to in-line fuel filter to boost pump to red cube, etc? For running in the tight confines of an RV4. Any reasons not an ok idea? Appreciate any thoughts.
 
I wouldn't..

I didn't find it that difficult to make hard lines even in the tunnel of the -4. Do some mock-up on the bench and make all the different pieces fit together, then put in the plane. Flex lines need to be easily viewed and inspected more often than can be accessed in the under floor of the -4. Read my recent post in the safety forum about a failed SS flex fuel pressure line that could have been catastrophic.
 
Wyn---+1 for Bills post on rubber hoses. Actually well done rigid tubes are in alot of cases better than hoses because of the tighter possible bend radius

Tom
 
Deterioration of automotive fuel hose.

I used Gates "Barrier" hose in several places in my fuel system. I'm seeing a fine black/brown powder collecting in my 10 micron final fuel filter. Could this be the hose deteriorating due to Avgas??
 
Has anyone used the black 3/8 ID fuel hose inside the fuselage, like from the tank selector to in-line fuel filter to boost pump to red cube, etc? For running in the tight confines of an RV4. Any reasons not an ok idea? Appreciate any thoughts.

Zenith kits use black fuel hose, you can buy it from them directly as a voucher of quality/compatibility. It's advised to replace it every five years; other than that, it works fine. It would be superior to aluminum in places where you expect vibration at the ends, but your fuel system really shouldn't have such runs (except the one to the engine, where you normally use firesleeved teflon-lined rubber hose).
 
I am not your Mom....but

Just be aware, "black hose" is not a specification. Fuel flowing in hose can create various levels of static charge depending on the velocity and distance from the last ground. Proper fuel hoses are lined with a conductive material to neutralize the charge.

So what is the failure mode? Since you asked, after a few inches, the charge can be over 30,000 volts and can discharge through the hose to a ground nearby. It will create a super tiny hole and will weep fuel. This not theory, it is fact.

Most leaks of this type are in the nuisance category, but wet fuel does present a certain hazard. In my personal experience, the perforations were at a grounded metal fuel hose attachment point and involved high recirculating flow. The diesel fuel weep was slow and simply collected dirt and dust.
 
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Bill is correct. Thats thats why real teflon hose is conductive. Remember the sprinker hoses we had as kids to cool off in the summer> well some of you might. Similar issues with high flow rates of most fuels. Yep rubber nullifies that, but the additives in the fuels deteriorate the liner. Yes---some airframe manufacturers use a rubber hose, or even an 'ethanol' automotive hose in the cabins. Zenith doesnt use rubber for the FWF anymore----as me how I know.

OH----and there was a client in AZ that had some so called fuel compatible plastic hose in the cabin of an award winning, high wing plane. Fuel additives deteriorated the plastic, and leaked the fuel out of the tanks into the VERY NICE INTERIOR. Took several thousand $$$ to repair the interior and replace the hoses with teflon.

So----we arent talking about lawn mowers and weed eaters here--

Tom
 
For those who are afraid to bend hard aluminum lines, start off with hardware store flexible copper line sold in a coil. It's great stuff to use for prototyping - bend it to fit, remove it and use it as a model against which to bend/measure/fit aluminum line.

For those who don't want to get into bending hard lines, just suck it up and give Tom/Steve a call at AS Flightlines - they'll treat you right and you will get very good hoses that fit.
 
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