With the body hoisted in the dump position, the reinforcing braces for the packer cylinder can be seen:
Here's what separates front loaders from other refuse trucks; the lifting mechanism. The twin hoist cylinders are conventional for 1966, carried parallel under the body, and pushing against bell-cranks welded to the torque tube. Though not entirely obsolete, underbody cylinders have mostly given way to the use of side-mounted, direct pull type cylinder arrangement.
Below is a closer look at the rear cylinder mounts. Attached to the cross-shaft is a body prop, on which the body is lowered during service to prevent injury or death in the event of a hydraulic leak. In between the frame is the main operating valve, where hydraulic oil is routed to specific circuits. A set of outside and inside-the-cab control levers directly actuate the spool valves.
Running between the frame channels are the pressure and return lines for the body hoist and packing cylinders.
Given the opportunity, Bill rarely fails to document the inner workings, and happily this day was no exception. We are looking forward towards the hopper area and the shallow top-pack blade, so called because it trims refuse only from the top-most portion of the load. The reasoning behind the top-pack is weight; with this simple, compact packer blade, a substantial amount of dead weight is eliminated when compared with full-pack and even conventional half pack designs.
Dangling from the roof edge are finger stays, which help keep compacted refuse from falling back into the upper hopper area.
Now here's the really interesting part; a follower plate formed into the packer blade, which is shown below partially extended into the hopper area. The follower was a feature specified by SCD when the truck was custom-built by Bemars. It prevents refuse from falling in the area forward of the packer panel, thus allowing the blade to cycle continuously, even while a container is being emptied from above. This is a great feature , especially as the body becomes filled. This feature was surprisingly not found on most top-packs of the day.
Next we see a view from the bottom of the hopper area, looking up at the framework of the fully extended packer blade and towards the front of the body. The shield also performs the vital function of protecting the hydraulic cylinder rod from damage. Nicks or burrs in the surface of the rod, as well as grit, will damage oil seals on the cylinder and cause fluid loss and premature failure.
A good look at the extreme edge of the follower plate, packer fully extended, as seen from inside the cab shield.
Of course Bill always brings back video from his missions, so enjoy this six minute video tour of a vintage Bemars front loader in action:
