A65-12 Overhaul

[Mike Magnani]

My first step in overhauling the A65-12 engine that came with N4094 was to send the crankcase, crankshaft and all the other steel bits to ECI down in San Antonio, TX. It didn't take them long to reject the crank because of a crack at the front main bearing area. I'm still waiting the results of the rest of the inspection. Used crankshafts don't seem to be in short supply so I'm looking around my local area for the best one to send down to ECI.
The logs indicate that the airplane was landed gear-up in 1976, which might help explain the damage to the crank.

[Keith Mackey]

Cranks are plentiful. As long as you case passes or is repairable, you're in good shape.

Keith

[Mike Magnani]

For a little bit more than the price of a replacement crank, I bought a fresh overhauled A65-8 engine that came out of a Luscombe 8A. Why so cheap? No log book, no accessories and the original owner deceased. So, I'll take it all apart and send the crank out to be certified. The goal is to end up with an engine that I can legitimately sign off as "Overhauled."

[Mike Magnani]

I just got word from ECI that my Crankcase, Camshaft, Connecting Rods & Rocker Arms have all been recertified and are on their way back to me. The Cam was able to be reprofiled and the Rods were re-bushed and balanced. The new wrist-pin bushings are .923", which is what the current TCM pistons call for. ECI rejected the 21608 Tappet Bodies but the manager suggested I send them to Aircraft Specialties in Tulsa. He said his NDT guys interpret the braze line as a crack and therefore reject ALL of that style Tappet. I'm going to send my magnesium -12 Accessory Gearbox to Tulsa, as well. I boxed up and shipped my replacement Crankshaft to ECI today. I hope it will fair better than the first one.

[Mike Magnani]

My -12 Crankcase is recertified and ready for Gray paint. The rocker arms and connecting rods are rebushed. I was glad that ECI Parkerized the reprofiled cam. I ordered a replacement Data Plate from Moody Aerographics. I hope to hear about my crankshaft next week. I sent the Lifter Bodies from the -8 engine to Aircraft Specialties and my Accessory Gearbox to DivCo, both in Tusla. My old S4LN magnetos went off to Aero Accessories for evaluation.

[Mike Magnani]

I contacted Moody AeroGraphics in Florida and found that they produce replacement Engine Data Plates. Here's the one I bought for my engine. I'll take it to an local engraver and have the information transfered over to it.

[Mike Magnani]

I just received the Lifter Bodies back from Aircraft Specialties. They ground the contact faces and Parkerized them. I also received the original Accessory Gearbox back from DivCo. In the picture you can see that they had to re-bush the Oil Pump Shaft Bores. I hope to get the Crankshaft and Prop Flange back from ECI next week, along with a new set of Rod Bearings, Rod Bolts and Nuts.

[Mike Magnani]

My Crankshaft and Propeller Flange came back from ECI today. The Crank had already been ground .010" under but the shop discovered that the Main and Rod journal radii were incorrect. The radii were reground to the correct dimension and the Prop Flange was ground flat and replated. I was able to buy new Rod Bearings and Rod Bolts from ECI but am still looking for new Rod Nuts and Main Bearings.

[Mike Magnani]

I masked off the drive pad surfaces and painted my Accessory Gearbox today. I used my 220 volt heater to bake the finish and a plastic crate to reflect the heat back at the casting. I was surprised at just how hot the whole thing got. My next step will be to assemble the Oil Pump and attach it to the inside of the Gearbox.

[Mike Magnani]

With my improvised oven, I baked the gray engine enamel on the case halves and gearbox. When everything cooled off, I gave the oil pump gears another pass through the bead blaster and assembled the oil pump.
I mounted my -8 engine, minus the crankshaft, onto the cockpit section so I can start remaking the cowl pieces. The old cowl bits are OK for use as templates, but I wanted an engine in place to make sure of a proper fit. I mounted the intake and exhaust systems so I can figure out how to route the throttle, mixture and carb heat cables.
The exhaust system, like the cowl, is only good for a template to make a new one.

[Gil Gilbert]

Mike,

If you need a copy of the drawing for the M-18C exhaust I can send you one.

Gil Gilbert

[Mike Magnani]

Gil, if you're going to be in Porterville, I can pick it up there. I'm planning on being there Saturday. Many thanks, MM

[Mike Magnani]

With the connecting rods attached to the crankshaft and the main bearings set into the engine case, I was able to lay in both the crank and camshafts. Per the information contained in Teledyne SIL 99-2B, I'll be using Loctite 515 to seal the case halves.

[Mike Magnani]

I sent my four best cylinders to Harrison Engineering and had them chromed back to New Standard diameter. All of the Intake and Exhaust Seats and Valve Guides were replaced, as well.
I bought and installed new 100 Octane Intake and Exhaust Valves, Valve Springs and Keepers. I bought +.015 Piston Rings so I could ensure that the ring gaps could be maintained to New Minimum clearances. The new pistons are 5-ring 80 HP units.