The Top 80 (and others) clutch is held in place by pressure against a conical shaft. No spline. It gets locked into position pretty hard and can be a pain to get off. There is an easier way than trying to pry it off with a screwdriver, not that anyone would try that because it would damage the soft aluminum housing. Yeah. Nobody.

So the clutch must be pressed off. A special tool makes the easy job but I don’t have it. And I’m an avowed hack mechanic so I came up with this. Hey, it’s what I had.

It takes a 13 mm socket for the 8 mm botls. This is a rube goldberg way to press it off.

The clutch has threaded holes into which a pair of 8mm bolts can be screwed. Drill a piece of steel ( used aluminum) with two appropriately spaced holes so two 8mm bolts (that you purchase) can go through. Place another piece of aluminum across the engine’s center shaft and tighten the two bolts until the clutch snaps free.

Remember, you’re a mechanic who periodically tests his work. Don’t forget to put that aluminum spacer ring back in place that goes between the redrive and engine. That space ring was required on some miniplanes like this one.