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Bob Weis · 05-27-2014, 03:16 AM

New RV, not new scissor jacks. Cleaning them up, repainting etc. Any idea where you can get the bearing that goes between the screw rod nut and the frame of the jack?

Thanks,

Skip426 · 05-27-2014, 10:58 AM

2 posts in 11 years ; boy are you shy.

Take a picture and the shaft diameter measurement to Auto-Zone or your nearest parts store ; they should be able to help.

PushedAround · 05-27-2014, 11:09 AM

McMaster-Carr and Graingers are also good places to look for bearings on-line.

Bob Weis · 05-27-2014, 12:59 PM

It is sort of an odd bearing. It has one side, then bearings, then the second side, not like a shaft bearing that the inner (axle) has bearings to the support frame. Sort of like a lazy susan, plate, bearings, plate.

Yeah, joined a long time ago, got caught up in work, just went semi retired and finally have some down time. Once I get my replacement trained in a year or so, should be able to be fully retired.

PushedAround · 05-27-2014, 02:24 PM

They're called thrust bearings. Check out this link.

McMaster-Carr

Bob Weis · 05-27-2014, 03:10 PM

From the web page they are shielded thrust bearings. I will measure them, but 1" I think.

So far a couple of things I have learned is the blocking washer on the screw side of where you crank the jack up & down is spot welded on and not even remotely aligned with the boss the screw goes through. Which makes the welded washer grind into the frame boss. I ground off the spot weld and pinned the blocking washer with a 1/8" x 1" cotter pin. Smoothed out the jack retraction significantly.

A new bearing on the jack extension side should make the rebuild complete. I replaced the bolts as well and you need to know that all 4 are NOT the same length. The bottom bolts (closest to the ground plate) are 1/2" longer than the top bolts. I used 3" with a nylock nut on top and 3 1/2" with nylock on the bottom.

Bob Weis · 05-30-2014, 07:59 PM

OK, I have the rebuild of the old scissor jacks coming along. Fixing the spot welded washer with a floating washer and cotter pin, cleaning up the mechanism, new bolts. They all work MUCH better.

Now I think I am NOT going to mount them permanently to the frame. I know you have to control any slip, so I am going to weld C channel C3 4.1# across where the RV frame would be. The C3 4.1# has exactly a 2 " flat landing and a 1.41 " high side that should fit the RV 2" frame really well. Why not bolt or weld them? I can place the jacks where I want along the frame and experiment until I find the best place that they stabilize the frame the best. I highly doubt that it will be at the extreme end on each side. If I decide to add another jack to each side I can do that where ever I want. Yes you have to carry them, but they should never be damaged, and they will be stored out of the weather and should last significantly longer and are rebuildable anyway.

I'll let you know how it goes after a couple of camping trips

Bob Weis · 06-06-2014, 12:10 AM

First trip with rebuilt jacks . Work perfectly . Now have 8 scissor jacks . Placed 1 under bedroom slide on frame , 1 just forward of the front spring frame attach point , 1 just aft of rear spring attach point 1 toward rear of frame. Duplicate on other side . Zero movement as you move around inside of rig . Very pleased with outcome . Also able to tweak side to side level precisely . Got side to side very close to level with levelling boards then snugged up jacks to frame and added 1/4 turn on all 4 jacks on that side. Lot of work setting up 8 jacks but for me it is worth the effort .