Installed the wing fuel tanks - 2 hours

Finally the day has come. I've waited a long time to finally get these tanks installed. I kept the wings in the wing stand for installation and it proved to work very well. Installation of the tanks is not exactly that easy. I slipped the tanks up onto the wings and once I was satisfied with the fit and everything was clear, I then used the jacks to help support tanks. I then began to install all of the bolts on the z-brackets. I installed all bolts initially and then began to tighten everything up little by little to ensure straightness. Once I had the bolts installed, I then installed the screws. and more screws and more screws. After that I torqued the z-brackets. Overall I am extremely happy with the fit...Very nice!

Priming the fuel tank back baffle - 1 hour

One of the last items on my to-do list before I install the wing tanks is to give the back baffle area some primer. My thinking is that this is an area where water, etc can ingress between the skin and spar so any primer will help mitigate corrosion.

Started wiring the fuel tanks - 2.5 hours

Well Great news! The leak test for the tanks held for 2-days. I'm declaring them leak free!!! What a frustrating process. Such little things make for a huge problem if not checked.

Now all I needed to do was to finish and secure the wiring on the tanks before I installed them on the wings. A couple of weeks ago I had my buddy Mike who is an AME stop by and show me how to crimp terminals for when I installed the ground wire. He was able to show me how I should install the lock washer/ring terminal on the fuel sender.

Now that I was ready to complete the wiring for the positive terminal, I was able to confirm that I have the assembly/installation correct. Once I had the positive wire installed. I then taped the wiring to the back baffle in intervals. I had discussed how to secure the wiring with Mike so that it doesn't rub/chafe once installed on the wing. He had suggested using a small dab of proseal. Taping the wiring down keeps it exactly where I wanted it to be. I used a service loop on the wiring around the sender to help ensure that wiring is not pulled off the terminals in the event the wiring is pulled too much in the future.

I mixed up some proseal and dabbed some on the wiring.

More leak testing the tanks - 4 hours

Well I came home from work to a bit of a surprise, the tanks had lost air, but not equal for both....So it’s not the barometric pressure that has fallen. I have a leak in the tank(s). After a small bit of swearing and the five stages of grief - I then put soapy water into a spray bottle and sprayed the entire tanks down top to bottom to see where the leaks may be. I couldn’t find any spot that was leaking. I was absolutely baffled. Maybe my solution is wrong? I sprayed and sprayed again, nothing. So I went upstairs and read more blogs after blogs. I had read in other blogs some folks experience leaks through the fuel caps. So I gave the tanks a good cleaning and used duct tape over the fuel caps to eliminate them from the equation. 
 
I pumped up the tanks and left them sit....About 2 hour later, I checked them....I still have a leak. Small but it’s there. Oh dear lord. The duct tape is slightly bubbled up around the fuel cap....yup those were a leak on the last round. But it doesn’t explain why the tanks are leaking now. I used the soapy water solution everywhere again. I stopped for supper and when I came back, I noticed bubbles around the fuel supply plug! They didn’t show up right away but it took time for the bubbles to build!
 
This must be it. I was so relieved as I thought for sure I had a leak in the tank. This makes sense for a potential leak point as I was so careful not to install the blank AN fitting too tight. I didn’t want to risk breaking the seal around the fitting for that AN fitting that I torque’d it to minimum spec. Also considering that there is no soft copper tubing between the mating surfaces of the fittings the risk of leak is increased. I took the plugs off and applied a small amount of tite seal on the threads and torqued the fittings on to mid level spec range. I double checked all fittings and re-pressurized the tanks. Fingers Crossed. Its 1:30am...way past time for bed!! Grrrr, I'm not going to sleep at all!
 

Started leak testing tanks - 4 hours

Now that the fuel tanks have had a good while for the last bit of proseal to set, I am ready to leak test. I was sure to buy two leak test kits. After much research on leak testing, I’ve come to the decision that the best scenario (in my opinion) it to test both tanks at the same time. This removes the every changing barometric pressure from the equation. First step was to rig up the lines that attach the clear tubing to the manometer that I am going to make. Using some short pieces of left over soft tubing, I flared the ends so I can attach them to the vent line connection.

Using a 2x8 piece of lumber I drew out a scale and used NMD90 (loomex) wire stables to secure the clear plastic tubing to the board. The marks were made at 1” gradients. I know have a large manometer. 
 
Next I took everything to my basement storage room where everything could sit and be left untouched. I then connected the fuel tanks to the ends of the manometer using two tubing clamps each (want to make sure all connections are tight). I then used some green food coloring to dye water and poured that into the manometer. I was sure that both tubes (left and right) where at equal levels. Then taking a small hand held bicycle pump I began to pump up the tanks to pressure. There is a limit to how many inches you can pump to, I’ve decided to keep things just under the recommended limit and stuck to 23”. Now since i’ve constructed my manometer so the tubing route goes down to the floor and then up.....every inch that is shown on the scale, actually represents 2” since the pressure makes the water move 1” down on the side and 1” up on the center. 
 
 
Straight away I could see that the levels where not staying put. I suspected that my Schrader valves at the fuel drain port where leaking. I used soapy water solution to check that area and sure enough they were leaking. After doing some reading, I removed the valves and applied some tite-seal sealing compound that I have (I was going to use this stuff to close the fuel access hatches on the tanks but decided to proseal last minute, glad that I was able to use the tite-seal after all) I re-installed the valves and pumped up the tanks. I double checked with soapy water....yup no leaks. Time to leave it over night and see where things sit. 

Finished riveting the Left wing rivets - 3 hours

Little by little I’ve managed to finish up riveting the wing skins. In retrospect, its a much slower process than every other blog that I’ve come across, however with that said I’ve done all the work solo and I was sure to check every rivet and can say with confidence that I have given it my best effort and I am proud of the quality. No question that once you have finished riveting the wing skins you’re a “master riveter” 
 

More left wing riveting - 3 hours

Just plugging away. Little by little. Working around the pitot mask is a bit tricky. Just more angles to work around with your hands. Progress is slow, but the rivets are nice.  One thing is for certain, this installation makes for a very solid pitot mount.


Here is a look at the inside mounting of the pitot bracket to the stiffener. I used bolts so all that is need to do is drill out 5 rivets and remove two bolts that hold the mast to the stiffener, and the pitot mast slides out of the wing. Without the stiffener the pitot mast is not very solid.

Misc wing riveting and more riveting the left wing skin - 4 hours

My order for cherry rivets have finally arrived allowing me to set the final rivets in the aileron brace. Since I have installed the Van's S.B. stiffener on the rear spar, the ability to buck the AD rivet in the rear spar at this location is near impossible. Ive chose to use cherry rivets in this location for their superior strength. Below shows how nice the cherry rivet clears the stiffener when set.


A bit more riveting on the left wing skin.



Here a good view of the two wing skin rivets along the rear spar that when the Van's S.B. stiffener are installed are impossible to buck. As an alternate I have just used MK-319 pull rivets for these two spots.

More wing skin riveting - 1.5 hours

In order to set the rivets closest to the access holes, I found that squeezing these does the best job. I just spent a little time this evening setting those rivets as well as a few more.