I just replaced mine,although I did it before putting in the cockpit
module - it is actually not too bad to do from the bottom and may in
fact be easier from the top - but you do need to cut out the headrests -
and be ready to totally destroy the old tank, and sand out pieces of the
tank that end up "resined" to the rear upright of the cockpit module - a
very sloppy job - the real problem when working from the top, as I see
it - is that you can't put in the channel or T pieces from the top -
you essentially have to work through the holes for the spars and the
bottom hole for the fuel outlets from the tank - I was thinking however
that part of the problem in this tank may be that we glass it in too
tightly in a few places and as it moves from expansion, it works the
plastic and we get stress cracks - this was the problem on my first tank
- the stress came from using too much air pressure to test the system -
but at best I only cycled the tank to expansion a few times - so if it
failed then, it isn't too much of leap to suggest that regular expansion
---From temperature changes could do the same - especially if the tank is
firmly held by fiberglass in a few places - the corner on the outside
edge below the overhang at top seems to be a particular place to
accumulate stress
Maybe it would be smarter when replacing a tank to build a shelf below
that the tank sits on and then strap the tank in with enough elastic
slack to allow movement of the tank - yet still have enough strength to
avoid the tank breaking loose in a crash - but the stress cracks I got
---From just a few cycles of air pressure really worry me -
Perhaps some of us could get together and fund the building of a
prototype aluminum (or something else) tank - once we had a design we
could easily reproduce it at much lower cost - I doubt if the factory
could do it because of the nannies in the English PFA - but we could do
it in the US - I would be more than happy to put a hundred dollars or so
to fund development - I don't know how many of us are worried about this
but 50 builders at $100 each - is $5000 - would this be enough to do
this? By the way a replacement tank is 110 pounds and shipping is
another 110 pounds - total cost is over $400 - just for the tank - and
maybe 30-50 hours to replace it - so is $100 worth of insurance each to
have a better fix available worth it? I think so - any feedback from
people that know something about the cost of prototyping - I know the
first one is always expensive - but the second one should be a lot
cheaper -
Gary Leinberger
A237
gleinberger@millersville.edu
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Venu Rao
Sent: Thursday, May 01, 2008 1:17 AM
Subject: Re: Europa-List: Fuel tank - bulges and leakage.
I'm rather concerned about this too. Going to have a look at my tank for
signs of bulging.
Almost certain I'm converting the mono to a conventional through Bob
Berube. Just need to price it out.
Do you know if the tank can be replaced easily?
This forum is invaluable!
Hope all's well.
Cheers
Venu
Cell: (512) 771-3286
On Apr 30, 2008, at 22:18, Fred Klein <fklein@orcasonline.com> wrote:
>
> On Wednesday, Apr 30, 2008, at 13:46 US/Pacific, Sidsel & Svein
> Johnsen wrote:
>
>> --> <sidsel.svein@oslo.online.no
>> >
>>
>> All,
>>
>> Preventing the tank from bulging too much forward will of course
>> prevent it touching any of the controls or the wing spar (in which
>> case the strap on the left spar might catch on the bulge during
>> withdrawal/installation).
>
> Before getting Svein's thoughtful and informative post (thank you
> Svein!), I spent some time looking for a solution to potential bulging
> in my tank (which came w/ kit # A194, shipped from the factory in
> fall, 2000).
>
> In order to "contain" the (outward) bulging, I reset my spacers
> (which have generous curves at the corners of the specified lay up) to
> ensure a gap between tank (dry and never filled w/ anything) of
> between 1/8" and 1/4" and maintaining 1/4" clearance from the aileron
> control rod, I was planning to do the following:
>
> Insert a piece of 1/8" thick plywood, 6.25" x 34", w/ 1 layer of bid
> each side between the spacers and the front face of the tank,
> cushioning the plywood w/ 1/8" thick "sill sealer" (I believe it is a
> closed cell polypropylene foam available in 6" rolls at any building
> supply) between the plywood and the forward face of the tank. Prior to
> insertion, I would add a 3/4" x 2" x 34" foam stiffener w/ 2 layers
> bid on the forward face of the plywood. The plywood would be held in
> place w/ a 2 ply bid 2" wide tape which laps onto the underside of the
> FG "shelf" (previously installed as per manual). In doing this, my
> goal would be to resist "bulging" of the forward face of the tank.
>
> Having reviewed Svein's post, I will not be doing anything until we
> have more information, hopefully in answer to Svein's questions on the
> nature of the HDPE used in our tanks.
>
> I do appreciate so much the value of this forum as we attempt to
> address this insidious problem.
>
> Fred
>
>
> --
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>
>
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