Section 18 Fuel Tanks

 

RV14 Build October

Fuel Tanks

To recap. My left wing fuel tanks was leaking when I tested it. I determined it was leaking from between the skin of the Aft inboard tank rib and the VA-141 fuel flange.

Testing the tank.

Leaking.

After talking with Vans they had me ship it back to them and they performed the repair. I received the tank back relatively quickly and tested it again just to be sure.

Matt made a shipping crate out of the crate the wing parts came in, nice to recycle!

The repair patch Van's had to cut and install into the tank.

Not a great picture, but I endescoped the vA-141 flange to see the repair and it looks like they added more sealant around it.

The tank tested well and Liz and I went to install it into the wing. Before I did I was reading in the plans and noticed the wing walk gap is dimpled but the holes in the tank attach bracket aren't. I spoke with Vans and they are supposed to be countersunk , but its not in the plans at all.

Quick countersinking while testing the tank.

There is a lot of screws and torquing the AN3 bolts takes a while, especially when you don't set the torque wrench correctly and strip 2 of the AN3 bolts. But we did it and finally got a working tank installed and reinstalled the push rod.

I got smart this time and installed the torque tube while installing the tank. It is WAY easier this way. I can move the torque tube up and down enough if I take out 1 set of bolts to install any washers that I might need.

This is where things took a nasty turn. I was using a ratchet strap to hold 1 end of the wing in the air while removing the work bench so we could put the wing back into the cradle and the ratchet strap unhooked itself and the wing dropped about 4 feet. The newly repaired and installed tank took most of the impact with the lower arm of the tank attach bracket assembly absorbing most of it.

Obviously my hart dropped with the wing and part of my soul died it felt like. But we removed the tank to inspect it and the wing. Thankfully the tank took everything and the wing looks undamaged. I was able to bend the flange back into alignment where the wing walk skin matched up.

There was 1 rivet in the corner that I was worried about so I drilled it out and re did it. I also added some preseal under the flange before riveting and then sealed the whole area.

After the proseal dried I tested again.......and it leaks. When the flange bend it separated the seal between itself and the skin.

For more on this saga look for the fuel tank repair post.

Fuel Tank 8.5 Hours

Section 40B : Tail Dragger Landing Gear & Engine Mount

RV14 Build September

Landing Gear and Engine Mount

Its about to look like a taildragger! At first i didn't have the engine mount Vans has issues getting them produced so I did everything I could without it and then mounted it when it showed up.

First thing was to assembly the wheels

Just to I remember in the future when I need to buy new ones.

The plans have you put the stem near the red dot on the tire for balance issues.

I removed the stem valve so I could inflate and deflate the tube numerous times to help it shift and seat around the inside of the tire. You can also see the tire has white powder on it, that's the talcum I used inside to help with chafing.

Next I cleaned the bearing of all the shipping grease and re packed them with Moble 28

Wheels are done for now.

Next I started on the tail wheel assembly. Mostly just had to prime the parts.

Then put them together per the plans.

Almost finished but the bolt that holds the tailwheel on is too short. I even tried going with smaller washers but I still couldn't get the threads to show. Vans sent a longer bolt to replace it.

New replacement bolt.

The plans have you make drift pins to help align the gear legs and the tail spring for final drilling. I ordered steel drill rods from McMaster to fabricate these.

Here you can see the wood block that you make to help clamp the part together after you center it. I used a regular punch for this picture, but the drift pins above is what I really used to center and final drill. For the final drilling I used a reamer rather than a drill bit.

For the first ones I was nervous to make sure the reamer would work and cut straight so I did it by hand. In the end I used me drill for most of the others.

Torque the nut to final setting, before you do this you do add a little bit of silicone around the washers to make this end water tight.

Next I had to repeat the process on the tail spring. I had primed the inside of the spring mount, that proved to be a problem now and had to sand out what I could to get the tail spring to fit in. The tape is just a visual so I would stop walking into it lol.

Drift pin installed before reaming.

Bolt is in and torqued. I think this is where you would but the tail tie down ring, but i'm not sure so a close tolerance bolt it is for now. You can tell its close tolerance by the shape of the bolt head.

Last thing I could do is install bolts into the spare where the main gear would mount on a tricycle gear. The AN5 were too short to have threads showing to I replaced them, even though the nuts were jam nut size not shear so I don't think they are structural. 

I tried to install the fittings for the brake caliper and messed up the threads. There must be a better wrench size for this. The second one was better, I just didn't try to tighten it as far, hopefully they dont leak.

The engine mount has arrived!

Was able to get it on the plane with relative ease, which was a surprise. Im always amazed at how well thing line up.

The bolt lengths on the bottom outside were a little short so I switch both washers to smaller ones. The top bolt only 1 washer needed switched out.

The fat washer.

Drift pin installed before reaming.

Gera leg clamped in place before reaming. really this is after because I forgot to take the picture.

Close tolerance bolt installed and torqued.

The axles are on and checking toe in and out.

I used feeler gauges to find the gap.

.027 and .025 so both sides within the tolerance, no shims needed!

Wheels are installed. The hole for the cotter pin was so tight it was impossible to get it in. It seems like its a 1/8" so I opened it up to #30 and that works much better. Im not sure about the proper tightness of the axle nut though. At one cotter hole there is the slightest amount of play side to side in the wheel at the next there is definite friction on the rotation of the wheel. Asked Vans what is more important, still waiting on an answer.

Brake caliper is installed.

Man does she stand tall!

That basically rounds out the gear. I'm ordering brake leg hoses from aircraft specialty which the next section of the plans has you fabricate. I'll update the post when I install those.

Tail Dragger Gear & Engine Mount 16.5 hours