Back in the saddle: Fuel Tank Sealing Story I've been off the 'net since my last move, I'm back at [email protected] for the time being. For those that have been keeping track, this is the fourth major move since the KR project started... but the plane stayed at the airport this time. (At least until the next move).
I just had a pretty good day of KR work. My wing tanks were seeping around the metal flange where the Capacitive fuel senders were, and I was sort-of fed up with working in fiberglass, so it took a year to get to it. (Work, Moving etc also was a factor... not to mention that I live 92 miles from the airport now.) I've got a really good 1 man rigging system set up for my KR. I have a wing dolly that both wings fit on when they are not on the KR. I also have a seperate wing installation jig that consists of two pressure treated 2x4's on wheels with removable carpeted stand offs. One end is reversable so that you can switch from left to right wing. One of the things I engineered into my KR was quick release fuel fittings on the wing. With these and the dollys you can attach and remove the tanks without draining fuel... up until now I had self draining tanks so I haven't tested this much yet with full fuel. I've had this setup for a couple of years now, and it seems to work reasonably well. I will take some photos and post it (soon?)... http://N541RY.com is off the air at the moment, but as soon as it's back I will have new photos. After putting the wings on I made a couple of calls on the radio from the KR to order fuel... if everything works as well as the radio setup, this is going to be one terrific aircraft when I finally get my life in order so I can finish it! Had the fuel guy put 6 gal in each wing tank. Last fall I had them topped off, 11gal each, and with the seeping saw most of the fuel go by-by. I did some searching on the web last year and found a good motorcycle site that had instructions on how to clean and repair fiberglass motorcycle tanks. Basicly, you buy some MEK, slosh that around until it runs clear, then clear that with Acetone. My tanks hasn't really had enough fuel in it to get dirty yet, but I thought running some MEK in them would be a good idea. After cleaning my tanks, I set them up for some light pressure testing with my air compressor. I have a nifty vacuum/pressure gauge that I put on a AN barb fitting with 1/8" thread. This was installed at the fuel drain point. The air compressor was connected to the fuel outlet, and I put tape over the fuel vent, and removed the fuel senders and taped that over. I pressurized the system slightly, just before the pressure gauge moved, then started listening... sure enough, I heard sound coming from the fuel sending flange area on both tanks. A few months later...I get out and mix epoxy. I decided to thin it a bit with MEK. MEK is an epoxy thinner... available through Aircraft Spruce or the Hardware store. This made the epoxy into kind of a sloshing sealer... then I poured this into the tank, and sloshed it around. (Remember to pull your sender, and fuel strainers etc... you don't want anything plugged with epoxy.) I had the fuel sender AN3 mounting screws installed, so the holes for that would not get plugged, and tipped the wings up on their end. After sloshing for a bit, I applied air pressure to see if I could force epoxy out through any holes... sure enough it worked like a charm! I pressure tested both tanks last week to about 1.5psi and only heard hissing out through the fuel filler neck. CAUTION: Tony Bengellis does not recommend pressurizing your fuel tank with air (As I recall). You could potentially de-laminate it if you don't watch what your doing. After a week of curing, there was some minor dremel work to open up the hole in the fuel sender flange, but otherwise no Homer Simpson "DOH" moments. This all ended nicely with me making some nice radio calls today "Corvallis Unicom Experimental fife four one romeo yankee, on the ground, request". Fueled around noon. No fuel dripping or seeping on the floor of the hangar as of late this evening (6:00PM). We stayed in town so I could check it... then did the 92 mile drive home North to Portland. (Yes I've moved again...) There is a slight chance that due to the wonderfull economy, I may get to move yet again before this is all over with... Texas is the next possibility Dallas or Austin. Won't move unless I can find a nice place for my KR to live. When I do finally fly to the KR Gathering, the KR will have more road miles than air miles... With the wing tanks properly sealed, I should be able to proceed with taxi tests, without being a major fire hazard in the hangar. -- ____________________________________________ http://www.operamail.com Get OperaMail Premium today - USD 29.99/year Powered by Outblaze
