PCW,
I remember one time we had installed twelve 9,000-pound capacity, floor-plate, two-post lifts in a Yonkers, NY dealership. After three months of use, the location continued having issues with the anchors loosening. The concrete floor was questionable at best – an old dealership with a floor that had to be at least 40 years old. Cracks, worn surface, more aggregate than concrete and at best, 3-3/4” deep. I was not present at the time of install so who knows the exact size or condition of the rotary-hammer drill-bit used. Eventually I flew to the location to assess the problem. On floor-plate style two-posts, the lift is void of the overhead support beam. Without the benefit of the overhead beam, there is considerably more moment load being placed on the anchors as a result of the columns trying to fall inwards.
After inspection I came up with perhaps the only solution - concrete anchor epoxy. I decided that although the concrete was less than desirable, the Toyota dealership rarely lifted heavy vehicles. Because the installers had drilled through the floor it was easy enough to pound the existing anchors deep into the ground below. Once the existing anchors were subsurface, I proceeded with filling each anchor hole with a two-part concrete anchor epoxy mix - kind of messy but manageable. I then proceeded to pound new Wej-it anchors into each hole making sure to tidy up any epoxy that flowed out over the surface. My intent was to make sure the epoxy had not only surrounded the bottom wedge portion of the anchor, but filled all voids subsurface, and surrounded the anchor to the floor surface. Before the epoxy dried and became unmanageable, I cleaned the threads, installed the washers and nuts then tightened each anchor to 45-ft pounds making sure the Wej-it “wings” had indeed spread into the surrounding concrete. I then returned the following day to give each anchor one more turn of the wrench to 75-foot pounds. I presume I could have achieved more torque as the anchors did not yield.
It has been over 20 years and the lifts are still working faithfully. They have not had a single problem with the anchors since. The same procedure was used eight years ago at a Pasadena, CA Porsche dealer with similar results.
Mflossin
Although I would not recommend it, I’m sure adding one more set of lock-bar holes positioned midway between the existing, would not be a problem. The lift columns were designed to operate at 150% load with no permanent deformation of parts. Our concern was that an extra set of holes would degrade the column integrity.
Jeff
BendPak
Appreciate the reply !!!