Good points all, Rich.
I am basically doing the conditional
now. I have the cowl off and am only running the engine to improve the tuning.
That is why I was inquiring about recommendations for fuel hose. With the
cowl off, there is a fairly stiff breeze that carries away any fuel
vapor. I do suspect that there was some kind of path of least resistance
that caused this problem originally. I now have two #4 welding cables
attached from each battery to each side of the starter which is mounted on the PSRU
plate. During this conditional, I plan to attach about a 12 ga wire from the
center iron to each battery just in case the ignition ground is looking for a
better path due to the sandwich you mention.
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of ARGOLDMAN@aol.com
Sent: Thursday, April 04, 2013
4:22 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re:
Replacement for Aeroquip fuel hose
This probably goes without saying, but it
is vital to determine why the arcing is happening. this may be a tremendous
safety issue for you (and others)
Arching does not happen in a vacuum
(actually it is easier there) but there is a reason. It is possible that your
electrical system is using your FUEL lines ( spelled lines full of FUEL) for
the grounding of somewhat high amperage loads, such as starter or alternator.
One thing to ascertain is " is your
engine adequately grounded". The engine mount is a poor conductor. you
need a good grounding strap (line) between the "-" of your battery
and the case of the engine. Since our engines are sandwiches and there is a
possibility (possibly remote) that there is some resistance between the bread
and the meat, your current, wanting the path of least resistance may be using
those fuel lines. Perhaps you need a better ground to the mounting bolts of
your starter and/or alternator.
I donnknow, if it were me, I would do the
fuel line inspection, correction and replacement NOW, before further starting of the engine.
By the way, what is your rationale for
delaying until the next conditional to correct a problem where there may be
significant current flowing through your fuel lines, especially when there is a
fuel smell. You don't smell liquid fuel, you smell the vapor. Lessee vapor
mixed with fuel in the proper proportions with some sort of ignition
system --lets say an electric shock-- may make your next conditional inspection
unnecessary.
In a message dated 4/4/2013 3:01:53 P.M.
Central Daylight Time, bbradburry@bellsouth.net writes:
I have several black spots on the SS braid for my fuel hoses they
look like they were caused by an electrical arc? I think I can smell fuel
around the spots. I plan to replace them at the conditional this
month. What fuel hoses are being used besides Aeroquip?
Bill B