Wednesday, March 30, 2011

Painting Engine Parts and Brake Problems

I've started painting the black parts for the engine, rocker covers, intake tubes, etc. The cylinders are next. I wasn't happy with the Cleveland wheels I had cleaned up and installed so I could get this thing back on the gear. The plane came with a mismatched set of Goodyear wheels and 4 brake calipers. I found wheels to match the Goodyears so I decided to clean up the brake calipers. After degreasing and stripping the old paint I quickly condemned all 4 calipers. All four have cracks in the casting at the edge of the machined area and the closest hole. Each is only cracked on one hole. I'm sure if I thought about how the braking loads are applied it would be obvious which were on the right and which were on the left. But who cares, I have more metal for the recycling bin. I've drawn arrows to the crack to help anyone else looking at their parts.

Thursday, March 24, 2011

Engine Case Painted

I couldn't find Continental Gray engine enamel, but I did find a Dupli-Color New Ford Grey at Advance Auto which is lighter than the Lycoming gray. It came out great. It was another paint with the recommendation to spray 2 light coats and then one medium coat ten minutes apart. After all the time spent masking I understand why Continental switched to Gold Alodine on the aluminum parts and their ugly Gold paint on steel parts. Even with clamp on masks there is a lot to mask. I pounded some dents out of the oil sump and I'm cleaning the Accessory case and other parts which get Grey paint. Fortunately the only inspection I needed to do was to make sure nothing got damaged after all these years setting. So far everything is fine. I'll probably paint the black parts before I start reassembly so the engine doesn't set open very long.

Sunday, March 20, 2011

Brake Lines In Gear Box

The new brake lines are fabricated and installed in the gear box. It took a few hours of careful work to get them so they follow the correct path and attach where they are supposed to. Fortunately 1/4" tubing is easy to work with.
I'm priming the fuselage under the 2 skin panels before I rivet them back on. After the riveting is done the gear can finally go back on.

Thursday, March 17, 2011

Fuel Lines & Selector Valve Back In

While the plane sat so many years the mud daubers had gotten into the fuel lines and brake lines buried in the landing gear box. With the skins (IPC fig 15-23) covering the gear box sides removed these are easy parts to replace so the gear has remained off while I get them done. The mud daubers had made it all the way to the fuel selector valve. Other than cleaning, the selector valve is in very good condition. The only problem was getting the rusty cotter pin out from the handle as well as the screw which broke at the cotter pin hole. After an easy out failed to remove the screw, I carefully drilled it to just short of the tap hole diameter for the 8-32 screw and then used a tap to gently remove the remaining threads of the screw. I need to verify that the valve seals but there were no scratches on the sealing surfaces. The fuel lines might have been cleaned but it seemed better to just fabricate new ones. I have this cheap tube bender which at least bends the right radius. The edges of the grooves scraped the sides of the tubing so some improvements were needed. I filed a slight radius on the corners of the grooves, then polished each radius with scotch bright and finally with the Dremel tool and polishing compound. To assure the aluminum tubing moved easily in the aluminum bender I also oiled the groove with a light machine oil, Problem solved. . The tool looks like it should be just held in your hand and bend the tube. That works fine for 1/4" thin tubing but not for the 3/8" x. 035" tubing used for the fuel lines. To get a tight radius you need to hold the bender against a solid surface to force the tube to stay in the groove while forming the bend. The result is a bend as well formed as the factory bends. . . . . . . . To prevent chafing on the fuselage structure the factory slipped lengths of thin rubber tubing over the aluminum before forming the flared ends. Lowes has a vinyl tubing of the same diameter and thickness which works perfect for this purpose. This worked fine for the new tubes, but some of the old tubes had been stored away from the mud daubers and didn't need to be replaced. The anti chafing tubing on some of those was cracked. On these old tubes people in the past had used various clamps, etc. to hold the anti-chafe tubing tight. Instead I used some heat shrink tubing slipped over the old tube and shrunk to a tight fit. The heat shrink I used was 1-1/4" wide laying flat. It was left over from my hang gliding days in the 70's so I don't remember the diameter.
This size fit nicely over the fittings and shrunk tight. Start shrinking in the middle, work around and then out. They came out great. I think these last 2 pictures are slightly out of focus.

Tuesday, March 15, 2011

Engine In Pieces

The engine is apart (the picture is before I split the case). I've started cleaning everything so I can inspect, measure , and re-paint. The prop hub is off to be overhauled (inspected & replated) so I can't reassemble until it returns and can bolt it to the stand. The only problem I've run into is finding some of the lubricants and sealants required by Teledyne Continental service letter SIL99-2B. A.E.R.O. had the silk thread (641543), 3D Permatex to stick down the thread, engine oil, and Paste-Gasket (642188). I'm still looking for Molyshield Grease and Dow Corning G-N Paste. I now have a lifetime supply of silk thread. In the past it came with the gasket set. I guess I'll just have to find more engine projects to use it up on. I like that idea.

Friday, March 11, 2011

Engine Work Begins

I've started taking the engine back apart. It's hard to imagine this project has sat so long but it was March of 1991 when Bolduc overhauled the cylinders. Maybe when we put it back together this time it won't sit so long without flying. I just want to make sure there is no rust or any other damage from sitting so long.

Tuesday, March 8, 2011

Engine Gaskets, etc.

The gaskets, etc. arrived to day from Fresno Airparts. It's always like Christmas when parts arrive. Now I need to get working on the engine so it can go back together. Everything has been overhauled but it has been setting for many years. I'll inspect all of it especially for corrosion and re-measure everything just to be sure it's correct then hopefully have it reassembled soon.

Saturday, March 5, 2011

Putting Things Back in the Fuselage

It's nice to finally be putting things back in the fuselage. The new nut plates for the gear leg wedge bolts are epoxy primed (no more rust) and riveted in. I have the materials to make the new brake lines. The float fittings were almost as much trouble to re-install as they were to remove, very tight quarters for big hands to work. The control yoke, flap lever, and all the other little parts I took out are cleaned, epoxy primed and painted. I love the Poly Fiber Epoxy Primer but I've never been happy with any of the enamel paints I've used over it on fittings. John Gaertner of Blue Swallow Aircraft turned me on to an epoxy spray paint from VHT Products Company. You can get it at most auto parts stores, they have a where to buy it page on their web site. You spray a light coat, wait 10 minutes another light coat, wait 10 minutes and then a final medium coat and let it dry to a very hard finish in gloss black or satin black.