Do the fuel tank finger strainers need to be pulled out and inspected at 100 hour or annual inspections? If so, I am having trouble getting enough clearance with the #1 wing rib to allow the strainer and its 90 degree fitting to be unscrewed from the tank. The SS7 manual says to relieve the #1 rib capstrip enough to allow rotating the fitting, but I find that I will have to also cut away most of the rib web in this area to allow the fitting to back out far enough to remove. You guys must have also run into this issue?
Jim
Also, even if I could get clearance with the #1 rib to rotate the fitting all the way out, it would interfere with the fabric on the bottom of the wing. Looks to me like the fabric would have to be cut or an access plate made for this area in order to inspect the finger strainers. Maybe nobody does this; that would answer my question.
During our build, I decided if it has threads - I should be able to un-screw it.
Here is what we did - 1) Cut enough relief off of the rib to allow the fitting to un-screw; 2) made an aluminum reinforcing plate for the fabric similar to what you do for the lift strut attach points on the wing to attach the fabric to; 3) made a small access plate which covers the hole and has a short screw on each end which goes into the reinforcing forcing plate the fabric is attached to.
One photo attached which shows the access hole when the wing was "in the suede" during the painting process. Not a real close up - but you can magnify the photo on the detail spot. Also don't have a photo of the cover plate but that isn't very complicated - just a little rectangular aluminum piece.
This permits both easy inspection and removing of the fitting and finger strainer.
This is a most complicated area since the Series V. The V I am helping with had the same issue. The original builder - 1995 - put straight barbs in for finger strainer removal. I don't know where he thought the fuel line would run, but it simply would not work. He also snugged the fuel tank up to the #1 rib so there was minimal room between the rib web and tank side. Our solution was similar to Dave, but I would strongly recommend a polycarbonate doubler as Rans uses. You can make the cover plate of aluminum and it screws to the polycarbonate with quarter inch pan head sheet metal screws.
A tip to those still building, use the space between the tank flanges and the capstrips of ribs #s 1 and 2 to maximize the space between the tank's side and the web of rib 1 - snug the tank up to rib 2.
I understand a "street elbow" will work, but what we did is modify the elbow in a lathe essentially cutting off the threads, then taking a bushing and modifying it so we could silver solder its threads onto the elbow in a more snugged up location. A lot of trouble indeed, especially after everything is finished.
Yes the tank will tend to unport on a descent if the outlet port is positioned as it was for the first 10 years, but that is why we install low fuel indicator systems, but, for Skystar to design no provision for finger strainer inspection could in the long run be more problematic.
Thanks for the suggestions. Still wondering if finger strainer inspection is a routine part of 100 hr/annual inspections? I am leery of regularly removing and reinserting threaded fittings in a fibreglass tank. It is so easy to damage the tank threads and get a good seal without overtorquing.
Whether it is a good reason to remove it pariodically? With my first IV Every drop of fuel loaded at home was auto fuel and run through a Mr. Filter. Numerous cross countrys and lots of avgas. One time at an annual when I always removed the finger strainers, I found a chunk of rubber about the size of my pinkie fingernail hiding just below the finger strainer. I presume it came from a card lock facility where the hoses had been recently maintained. That in 900 hours. I plan on doing it again each annual, but I guess to each his own. I don't know anything about the high tech thread sealant guys are using now, but I use Fuel Lube as a sealant and it stays soft and didn't have seepage problems with the periodic removals. Consider ten times in ten years not a frequent event.
Regarding the strainer in the tanks, I bought a model 2, which was about 10 years old. Fuel from one wing tank basically didn't flow (from a practical standpoint), the other was slow. I don't know what was plugging the strainer, but I could not remove the strainer, as it had been glassed in. So, yes, I think you should inspect it, or at least check your fuel flow from the wing tanks (though all filters and fitting would be best). On mine, to clean the strainer I drained the tanks best I could and removed the filler cap. I blew a few quick burst of 10 PSI air though it to back flush the strainer, then siphoned out the remaining contaminated fuel. Added a bit of fuel, and repeated until I could not see any solids in the sucked out fuel. I am sure it didn't remove 100% of the contamination, but it did restore full usable fuel flow and I didn’t have to repeat it again over the next year Hope the helps Roger
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