The Mooney’s engine overhaul is underway!

The last time we saw the Mooney's Engine it was hanging on an engine hoist. It looks a bit different now. The folks at Pinnacle Aircraft Engines are also expert carpenters. Check out the construction of the shipping crate.

It was a simple matter of attaching 4 struts to the exhaust flanges and placing the struts onto the 2×4 bracing in the crate. A couple dozen screws later, this engine isn't moving in its carrier.

The engine arrived at Pinnacle and they began the teardown confirming what we suspected…. And more.

Warning, the following images are NSFW (Not Safe For Wallet)

My inexpensive borescope gave us some indication that there was damage to the cam lobes, but once it was removed from the engine the extent of the wear was surprising. In the photo below you an see the gouging on the lifter face, and if you look closely you can see where metal is actually rolling over the edge of the lobe. JD at Pinnacle said a quick way to check for a damaged cam is to run your fingers on the edges of the lobe, it you fingers come back bloodied, you can plan on a new cam.

If you are wondering where all this wear is coming from, just one look at the face of the lifters will explain everything. The lifters are supposed to be mirror smooth. These look more like the surface of the moon. The cam lobe has been running the rough face of the lifters and it is slowly grinding metal away.

The metal bits have found there way into all parts of the engine. you can see the gouges in the piston skirt below. Similar scoring was also seen in the oil pump. Bits of metal also contaminated the propeller governor causing it to be condemned. Fortunately I was able to locate an used/overhauled governor from West Coast Governor Service.

More to come…

Propeller overhaul is done!

As you saw in my previous post I have removed the engine, propeller, and accessories off the Mooney and have been busy shipping them out to specialists across the country.

First off was the propeller. Taking it off the plane was easy. Packing it securely to make a trip to Stallings Aircraft Propeller in Arkansas involved help from one of my neighbors to construct a custom shipping crate to cradle the hub and protect the blades.

The propeller arrived undamaged and the technicians at Stallings began the disassembly and inspection. Unsurprisingly, the propeller and hub were in need of attention. The propeller was installed on the engine back in 1997 and in that time it has been trouble free. No grease leaking from the hub, no vibration issues, basically no reasons to warrant removing the propeller.

Age does take a toll, and that was evident when the blades were removed and the hub opened up. It turns out there was almost no grease in the hub, and a small oil leak had started near the pitch rod. This leak was actually helping the propeller protect itself as it kept the rod lubricated.

The bearings also showed signs of corrosion and pitting, necessitating their replacement

The blades were then stripped of their paint and surface corrosion was cleaned up. The blades were then alodine coated to prevent corrosion and a new coat of paint was applied. Not only will it look better, it should be smoother too, one blade was almost 70 grams heavier than the other.

Here is a before picture:

And look at it now!

It will look even better once it is installed on the overhauled engine.