opjose

The only caveat mounting the engine upside down, is idle tuning.

Use the "ignitor" trick to make sure the LS needle is set properly, then adjust the HS needle and go back and double check the LS again using the same trick.

The "ignitor trick" is as follows:

- Start the engine and let it warm up, you can even do this with the plane inverted ( engine upright ).
- Adjust the low and high speed needles as much as possible
- With the plane upright, remove the ignitor and observe the behaviour of the engine at idle.

If:

- The engine slows down or stops the engine is too rich, Lean it out 1/4 turn and try again.

- If the engine does not slow down richen the engine 1/4 turn and try again.

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- Remove and install the ignitor until you find that point where the engine just begins to slow down, lean until this stops
- Now richen the engine 1/8 of a turn and check the HS needle again.

This will prevent the engine from bogging down in flight or on the ground.
Don't forget a nose up test too.

When starting the plane, assume it needs very little priming if none at all.

With most of my inverted mount engines I use an electric starter and I do NOT prime the engine at all.

I let the starter turn the engine over until it starts.

Other than that, having the engine inverted is no different than an upright installation.

You DO want to close down the throttle and keep it that way once you stop the engine to prevent fuel from leaking into the head.

Also before you install the ignitor and hit the engine with the starter the second or subsequent times of the day, make sure you can turn the engine over fully.

The idea is to prevent hydro-lock.

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On that plane, you'll put the cowl on. The head will hang down, and then you install the muffler assembly.

Likewise to remove the cowl you'll remove the muffler and pipe first.