With a single bolt threaded up into the (threaded) plate on the engine mount, one could install a jam nut on top of the plate. The possibility of that coming loose would be pretty slim. Also, that single bolt likely only holds the engine mount to the engine, with two independent bolts going down thru mount to the frame with prevailing torque nuts on them. That would allow the mount to have some vibration dampening effect. On the AD series front mount, there's no metal-to-metal connection between the engine and the frame. Two bolts hold the mount on the engine and another two hold the mount to the frame separated by the rubber insert. The nuts for the engine to mount bolts extend thru oversize holes in the crossmember. Attached is the cross-section of the front mount from the 47-51 Shop Manual.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
