Building, testing and operating an experimental aircraft

Hanging the Engine

17 Dec 2014

With the holiday season close at hand, the stars fully aligned, and the shrink wrap peeled off, Dad and I had no choice but to hang the engine.

Engine on the Hoist Engine on the Hoist

After shopping around for engine hoists on Craigslist, we eventually got a sweet deal on a new Pittsburgh 1-Ton Foldable Shop Crane from Harbor Freight Aerospace Supply, and it performed like a dream.

Pre-Hang Checks Pre-Hang Checks

After six years of assembling aircraft structures, Dad and I have gotten pretty confident when it comes to working with raw aluminum. Suddenly, here we were, forward of the firewall, in uncharted territory. We literally had no idea what we were doing.

For guidance, we turned to EAA’s Tony Bingelis books and Van’s 27 Years of the RVator, which includes the wonderful “Illustrated Guide to Engine Hanging,” also available on VAF. This guide is invaluable, since the documentation that comes with a new Lycoming is sparse at best. Van’s normally-detailed plans also seem to taper off a bit in specificity when it comes to firewall-forward items.

Engine in Position on the Mount Engine in Position on the Mount

Thus, before moving the engine into position on the motor mount, we installed the oil system fittings mentioned in the Guide. In our case, the only really critical item was the oil pressure fitting, which is located almost on top of the upper right mounting point. It’s important to get this one in before mounting the engine, since it’s basically unreachable afterwards.

Engine Ports of Note Engine Ports of Note

One of my big pet peeves with Lycoming’s documentation is that they send you information on multiple engine models, instead of just the one you own. I suppose it saves on printing costs, but it doesn’t help the newbie installer when he’s trying to figure out what everything is. We got lucky with one or two excellent VAF threads on port identification to help us out.

Aligning the Holes Aligning the Holes

The second “gotcha” that we encountered was that Van’s had shipped us the wrong mounting hardware, the significance of which we only began to fully comprehend when we were on Bolt #3. Van’s had sent us four AN7-43 bolts, when we really needed only two of them, plus two AN7-44s.

We discovered this error not while taking inventory, and not while reviewing the engine mount plans, but only after trying to tighten down the nut on Bolt #3 and running out of threads. Luckily, Van’s shipped us out the hardware we needed without a fuss.

Yanking on the Lord Mount Yanking on the Lord Mount

The last bolt on the dynafocal mount is, of course, the tricky one. So a couple days later when we had our AN7-44s in hand, we tackled Bolt #4. We used the “drift pin” method mentioned by others to coax the rubber mount to align with the engine’s bolt hole, but it kept wanting to snap back to its original orientation.

In the end, I decided to use some of my old rock climbing hardware to convince the Lord mount to stay put. I yanked on the mount with an old kevlar sling and a carabiner, while Dad got the bolt started. It worked.

Inserting the Cotter Pins Inserting the Cotter Pins

After all the bolts were inserted and the nuts installed, I torqued the bolts down until they stopped against the Lord mounts, then Dad installed cotter pins in all of the castle nuts.

Backing Off the Hoist Backing Off the Hoist

After everything was tightened and safetied, we lowered the tension on the hoist and backed it away. And just like that, the powerplant was installed! Woohoo!!

Frosty Beverages Frosty Beverages

Dad and I celebrated with frosty beverages.

Menards Aviation-Grade Coozies Menards Aviation-Grade Coozies

Shameless Menards plug…

Enjoying Victory Enjoying Victory

We took a minute or two to enjoy the fruits of our labors, and then we looked forward to some real wrench-turning in the days to follow. I guess I’ll finally have to learn how to install safety wire…

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