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I've noticed a recurrent theme over the years with hydraulic mounting points breaking off on the 320/360, and I wouldn't be surprised if it happens on other fiberglass airplanes either.  IMHO, here's how to keep it from happening.

What I did was to pressurize the hydraulic system with the gear down.  In the 320, that's 500 psi or so.  Then, you disconnect the battery or pull the pump circuit breaker to keep the pump from turning on accidentally and cutting off your fingers.  Adjust the rod end on the cylinder rod so that the bolt connecting it to the overcenter linkage slips in easily.  Turn the circuit breaker back on and verify that the pump did not turn on, i.e., that you really did have pressure in the system when you made the adjustment.  Then cycle the gear to ensure that the wheel location in the up position is still acceptable.

If the gear is misadjusted, you can have large forces pushing the overcenter links closed -- Guess what happens at the other end?  The mounting point breaks off (maybe not immediately, but eventually).

I'm no expert here -- my 360 is still in my garage, a long way from flying.  But I gotta believe that broken mounting points are often caused by incorrectly adjusted gear linkages.  And in my recent testing I have discovered that the linkage is a different length with the system pressurized.  Not by much, mind you, but probably enough to cause long-term problems like we've been seeing.

- Rob Wolf

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