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)
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
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
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
Of course, I couldn't resist bolting the Prop on just to see what it looks
Hanging the Engine
Total Time: 2 hours
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