English to Czech Tech/Engineering Mechanics / Mech Engineering zařízení pro golfová hřiště, core harvester

Next adjust the upper spring adjuster screw until 30 to 40 pounds is required to lift the lower end of elevator with a spring scale.
Raise the elevator assembly using the lift handle
The handle MUST go “overcenter” with positive action.
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Další kontexty asi se stejným významem "go overcenter" lze nalézt na netu.
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