Hanging the Engine

Started 02/21/06

My Lycoming O-360 has Dynafocal 1 mounts.  This means the mounting bolts are angled toward the center of the engine rather than straight and parallel with the crankshaft like a Conical mounts are.  The engine is mounted through some rubber bushings to isolate the vibrations and not send them through the fuselage.  I used the homebuilder bushings from Aircraft Spruce (P/N 08-03500) which are the generic equivalent of Lord Mounts (#J-7402-5).  These are made for the Lycoming O-360.  If you are installing an O-540 or other engine, you will have to do some research to find the proper mount bushings for your engine.

Installing these mounts can be somewhat frustrating as it is sometimes difficult to get the bolts aligned unless you follow the procedures outlined below.

1. Using an engine hoist, lift the engine up and align it with the mount.  

2. Slip in the inner mount bushings for the top two mounts.

3. Now assemble the Pilot's side (Left side) top mount bushings, bolt, washer(s) and nut.

4. Tighten and torque the nut/bolt down all the way.

5. Next assemble the passenger's side (Right side) top mount bushings, bolt  washer(s) and nut.  Torque that one down completely.

6. Now with both top mounts installed and tightened completely down, its time to install the bottom mounts.  Start with the Pilot's side (left side) bottom mount:

Again, tighten it down completely.

7.  The final one is maybe the biggest challenge.  If you have everything else aligned and torqued down it should be fairly close to being aligned.  You may have to loosen the top mount a little to get the inside bushing in.  Once you get it in, re-torque the top one before trying getting the bolt in.  If the bolt will not slide right in, avoid the temptation to hammer it in.  It's better to use your ratchet wrench and screw it in if needed.

That's it.  The engine is hung:

One note of caution - If your wings are not mounted yet, you might find the tail a little on the light side.  To prevent having your fuselage tip nose down unexpectedly, put a sand bag or some other weight on the tail:

Of course, I couldn't resist bolting the Prop on just to see what it looks like:

Hanging the Engine

Completed: 02/21/06

Total Time: 2 hours

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