We're restoring an '87 quad runner, it's sat in our garage for over 3 years and the throttle cable was seized. It seemed in good shape so we tried penetrating oil. Came up with a great idea, not sure if it's a common practice or not. We sprayed the oil in the adjuster nut opening and sucked it through the cable with a shop vac. Held my had over the vac hose with the cable between my fingers. You could see it suck the oil down and in to time the cable was free and we had a quick test drive.