As has been speculated on the Velocity list; it appears that
there is a coating of the underlying epoxy on the Jeffco fakes in Chris’s
tanks; so we don’t know that the problem is with the Jeffco. The
underlying epoxy is EZpoxy. It has also been speculated that the auto fuel
may have leaked through a pinhole in the Jeffco and then damaged the EZpoxy.
I emphasize the ‘speculated’, since that’s all it is at this
point.
Here is my comment regarding EZpoxy and
auto fuel:
“I can’t offer anything
additional as cause, but I wouldn’t hasten to put the blame on the use of
auto fuel. There is no evidence that I am aware of that EZ poxy; when
properly mixed and cured, has any incompatibility with the fuel. There
are EZ flyers that have used auto fuels for 15 years without problems.
I’ve had auto fuel in my tanks for
6 years, and haven’t noted any evidence of damage to the epoxy. I
did have a few pin-hole leaks on the inner skins, and then found that the fuel
had wicked through the glass plys in the skins that had not been completely
wetted out at the factory. I attributed those leaks to me not being thorough
enough in coating the very porous skins on the strakes as delivered. There is
an EZ flyer (Perry Mick) in Oregon who has used fuel with 10% ethanol for years without an issue.
The caveat, of course, is perhaps the
issue that Joe raised about the proper mixing of epoxy used.
Back when I was finishing my strakes
– I guess about 9 years ago (yikes!) I talked with the folks that made
both EZ-poxy and Jeffco. The issue of good bonding of one to the other
did come up, and the uncertainty of the coating adherence was enough for me to
decide against it. That apparently changed later.”
FWIW,
Al G
-----Original Message-----
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Bill Bradburry
Sent: Tuesday, August 12, 2008
8:33 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Jeffco
Problem...worst day as a builder
Chris,
My heart sank when I saw those pictures. I
have been concerned about my plane having the same problem. Florida has
gone to all 10% ethanol all over the state, so pure gas is not available.
I need to fill my tanks in order to calibrate the gages but the gas will be in
the tanks for a long time. Probably till I fly.
My tanks were sealed with ProSeal and I really
don’t know how resistant it might be to ethanol.. Have you had any
ethanol in your tanks?
I hate to fill the tanks with av gas because of
the plug fowling problems, but I would REALLY hate to be facing your problem.
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Christopher Barber
Sent: Monday, August 11, 2008 10:29
PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Jeffco
Problem...worst day as a builder
Well, this was the worst builder day
I have had. That includes the day I realized I had to build a new rotary
engine, which, btw, was running better each day before this fuel issue
developed.
As the collective from the various list I am on may recall, I have had
persistent fuel leak issues. A few weeks ago I had a visit from the fine men of
the Ellington/JSC/NASA fire department when I leaked a few gallons on to the
hangar floor while I was at home sleeping late. Also, I thought my original
clear factory tubes failed due to ethanol. They had turned color and became
brittle (turns out they had not YET leaked.
I tried sucking new Jeffco into where I thought the leak was (very hard to
reach area behind the spar. I found a loose hard point and since I was having
some fuel seep through the floor of my cabin I thought maybe the fuel was
seeping in behind the hard point into the foam to the cabin floor. Since the two
hard points from the strake fuel line were both put in per plans years ago
(before my choice to use a rotary, thus auto fuel) they were installed with
EZ-84/flox. Since the flox around the loose hard point seemed a bit
"off" I decided to redo both of them with Jeffco. At the same time I
also took out the factory fuel elbow fittings as mentioned above and installed
Vance Atkinson's gages. I did this over the last few days.
I thought all was well, but when I added fuel to the right strake only, I still
had fuel seeping through the cabin floor. So, I am having fuel leak though the
inner foam. I spoke with Velocity, Inc who stated I could either go into the
inner skin around the stake storage area or cut a hole in the top of the strake
to find the leak. I chose to go into the top of the strake as I thought it
would be better to not try to patch a leak from the outside. So, I cut a hole
in the strake to apply Jeffco to try to find/cure the leak.
EEEEEEAAAAAKKKKK. I opened up the top right strake and the Jeffco on the top of
the strake was sitting in the bottom of the tank. OMG!!!!. Almost all the
Jeffco from the top of the strake had fallen off. It was all flaky and not
adhering. Also, a number of places from the sides and bottom had also fallen
off.
I called Velocity, Inc and they said they had never had this issue before. They
suggested I look in the other stake to see if the problem was there too. We
discussed when I applied it and how. Now guys and gals, I am not a complete
incompetent. I know I sanded stakes before I applied the Jeffco, I mixed it
well and per instructions. Also, the top strake Jeffco was applied at a
different time/batch from the sides/bottom. The Velocity top strake is a
pre-built piece and is laid on the strake sides/bottom in a separate step and
the Jeffco is applied to the top before you seal it, then you seal it with more
Jeffco.
I have never had more than about 20 gallons of fuel in the system (about 60
total capacity). I have had the fuel sit in the strakes for a long while
though. I used the Jeffco since it is supposed to be more resistant to fuels
like diesel and auto, even with ethanol...at least that was my understanding.
Some ares of the strakes seem pretty good (but I don't trust any of it now). I
did get TWO, one gallon kits of Jeffco back when I did this part of the build.
My first thought is that perhaps one of the buckets was a bad batch. Donno.
I did cut into the pilot strake too. It was not as bad. The top of the strake
looks good, but I do have some flaking on the sides. There are four
compartments in each strake. I cut into one on the co-pilot side, and three on
the pilot side so far. One on the pilot side seems perfect (so far). The
inconsistency has me confused currently. But to be honest, after dealing with
this for a while and trying to be philosophical about it...such as I would much
rather find it now, I walked away and worked on re-attaching my ailerons after
balancing them.
So, it seems many of those other
fuel issue may have not been the problem I thought they were....this does seem
to be the cause for when the fire department came out as that leak just seem to
happen. When I pressure tested this system a few years back, all seemed
fine.
I am posting the pix on the Canardzone but I am posting this message on a few
sites like FlyRotary and the Velocity Builders site. The factory asked me to
post too so they could have a look and determine if this may be a isolated
incident (such as me missing something big) OR if it could be a bigger problem.
Well, here are some of the pix I took....if they are blurry, don't worry, it is
only my tears......