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…

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