2 post lift arms sagging a bit?

[1dumbquestion]

Hello all, just installed a used Worth 9000lb 2 post lift in my home shop. The arms seem to sag a little. They don't bow or bend but do not stay square to the upright. I assumed the 2 plates that go over the tube had spread over the years but on measuring them they are the same at the inside next to the gusset as the far outside where you'd think they had spread. The tube they sit on is 4" and the ID of the welded plates is a strong 4-1/8" so they just sort of tilt downward. Doesn't seem to make a difference just makes me nervous. Anyone have experience in this area? Thanks, 1

 

[James-W]

Maybe it is late and I am just tired, but I am not sure exactly what you mean. Any chance you could post a few pictures?

 

[mhejl]

I have a newer Worth 9k and have similar issues. It isn't a problem, just the rather sloppy tolerances in the various carrier parts that ride in the vertical posts, the nylon rub pads, etc.

 

[winkeldc]

Have you contacted SVI International? They might have a solution; I looked into getting shims for in between the carriage and the arms to correct the sag, if I am picturing your problem correctly.

 

[gungatim]

mine sag as well. needs new bushings in the arm pivots. if it's used like mine, it probably has the same issue.

 

[1dumbquestion]

Pulled the arms and took some measurements. Pins are true and round and mic within a couple thousands of 1.500. The drilled holes in the arms are just a few thou over and hold the pins well. Sure enough the bushings welded in the upright tubes are as much as 60 thou over so arm and pin are tilted in the bushings. I know it can't go anywhere but I still don't like the way it looks. Might have to hack it up with the plasma and weld in some new bushings. Thanks, 1

 

[gungatim]

are you sure the bushings are welded in? usually they are bronze. mine are just pressed in and have a grease zerk. if they are steel and welded that is a poor design, IMO...

 

[gorilla]

Pulled the arms and took some measurements. Pins are true and round and mic within a couple thousands of 1.500. The drilled holes in the arms are just a few thou over and hold the pins well. Sure enough the bushings welded in the upright tubes are as much as 60 thou over so arm and pin are tilted in the bushings. I know it can't go anywhere but I still don't like the way it looks. Might have to hack it up with the plasma and weld in some new bushings. Thanks, 1

A better solution would be to take the arms and uprights to a machine shop that has a big mill or a horizontal boring machine and have all the parts line bored and them make oversize pins. Not cheap but better than hacking it up with a plasma.

 

[1dumbquestion]

Update. Instead of hacking away with the plas I spent some quality time with my die grinder. Was able to grind out the bushings at the weld and remove without altering the original drilled hole. Replaced with 4" sections of 2" x 1/4" wall DOM that I had machined to fit my pins. Welded them in the crossarm which is 4x4x3/8 square tube. Arms are nice and level now. Funny thing is only the 2 on the drivers side were worn and oversized the other 2 were within a couple thousents of the pins. Anyway, thanks for the advise, 1