650 Starter Delete Plug

I just did this to a 501 a few months ago and I wondered the same thing. I recently looked at a parts manual and the picture in the manual indicated that the plug is supposed to have a step in the outside diameter that keeps the plug from falling into the engine. Also, the picture showed a screw and washer on the inside of the engine, presumably to keep the plug from falling out. In any case, the plug I received had none of these features. I drilled and tapped a hole in the middle of the plug and then drilled and tapped holes in the engine case on either side of the starter hole. I think that the holes were 4mm. Then I built a retainer out of thin aluminum and drilled 3 holes in the retainer that match the locations of the 2 holes in the engine case and the 1 hole in the plug. With the retainer screwed in place, the plug can neither fall into the case, nor fall out. I'll take a picture when I get a chance.

In retrospect, I imagine that the plug is meant to be bonded in place with some sort of adhesive since it was supposed to be used in the MX models and the ability to remove the plug was not of high importance.

VOR, I work for ICON Aircraft where we build the A5 LSA. We use the Loctite sleeve retainer in many locations and my experience with it has it being somewhat brittle once fully cured. My fear is that engine vibration might lead to failure of the adhesive. If it were me, I'd use a 2-part epoxy to secure it.

the one on my 02 650 just pushed in and stayed there

The bung I have just removed from a 2002 fe650 has the washer and bolt retainer.

you still have the kickstart decomp fitted?
you old fossil you! get rid of the bloody thing!

Taffy