![]() |
Bed Hoist Background |
||
By
53MoneyPit
|
|||
Anyone who has ever unloaded 10 yards of anything from the back of a truck by hand knows that gravity is a much better method! For those needing some background on bed hoists for the larger trucks, here's some info gleaned from a Discussion Forum topic.
The
hoist in the picture is
likely a Perfection model 715 LP or a Galion 715. It has no subframe as such,
only an angle running forward for attachment. These were used on early 40's-60's
trucks as conversion hoists for platform bodies and farm bodies. The photo looks
to be a wood floor so I am assuming it is a platform body.
DUMP BODY hoists on the other hand had a 4-5" high channel subframe which ran the full length of the hoist and the hinge area was part of it. The cylinder was pushing against a tri-angular lift arm arrangement or cast iron cam & roller setup (Converto Mfg. only). These were usually a little longer stroke cylinder (approx. 20") for an 8' dump body. The bodies were typically 8'L x 78"W (ID)and about 16-22" high.
THE FRONT BULKHEAD and tailgates were typically 6" higher than the sides. This would have made them 3-4 yd capacity. This is for the small "2 ton" size chassis that used 7:50 & 8:25 x 20 tires and had 60" C/A dimensions. Larger chassis were typically 9-10' long bodies of 72"-84" C/A dimensions for single axle trucks. These subframe hoists were originally made to stiffen the truck frame and caused the bodies to set higher for added tire clearance.
Nearly ALL the bodies of that era were made of 10 ga. mold steel and used 3" or 4" channel crossmembers on 12"-16" ctrs. Most all had flat rubrails and tapered sideposts of various designs that were either skip or solid welded to the side sheet. Floors generally had a center full length seam and ALL had a flat top rail of either 2 or 3 bend design. Tailgates were also 10 ga. and had either one horizontal formed brace or two vertical formed braces. Hinges were usually made from cast iron and the lower hardware latched up on tailgate lower pin from the bottom side, but occassionally one would see it closing downward from the top as is done today.
The pumps were low-pressure (1,000 psi) and were cast iron gear type that ran directly off a PTO shaft from the tranny. ALL the 40-50's units used floor levers and these were still popular and considered standard equipment well into the 70's.
PTO's were Chelsea, GarWood, Tulsa and later on, Muncie. All were cast iron and nearly always a single gear type.
Hardware operators were cast iron and located at the front drivers side. These were simple over-center designs and had threaded 1/2" rod and clevis at the rear where they attached to the cross-shaft. I may still have some old literature in my files from those days but not likely after so many years. CABLE operators were not of sufficient strength or reliability to operate the pump valves until late 70-early 80's. Also NONE of those early PTO's had provisions for attaching a cable operator in those early years. All were a shift rod design.
If it has twin cylinders and is of 1949 era, i.e., an original hoist, then it is definately NOT a dumpbody hoist but rather it is a conversion hoist commonly used on grain bodies, etc. Glencoe was a popular product as was Perfection-Cobey and a few lesser known brands. (Johnson, Galion, Marion to name a few) Interestingly none of these companies are in business today. Two of the brand names still exist, Galion and Perfection, but are only shadows of their former selves and the product lines are vastly different from the 40's-80's.
If your hoist has a Williams pump/valve/reservoir assembly in one unit then it was made for a cable control but these weren't available in the 40's, only cast iron gear pumps as I have previously stated. The inexpensive Williams unit was and is common on conversion hoists manufactured after approximately 1970. Cables became popular on PTO's in the 70's. Either of these two, the pump or the PTO could have easily been replaced over the years so it is really impossible to say if your unit was installed after 1980.
Hope some of this information is of value to you. Believe me, it is all accurate and I paid my dues to learn it. I have been in the business for 40 years and have worked on dozens of these old things.
No parts of this site, its contents, photos or graphics may be used without permission. |
|