Dover IVO Jack Manual

I have a Dover 2-stop IVO jack that has a real bad rumbling/thumping coming out of it while running up. I found and replaced two bad guide rollers and thought I had it whipped. I know that the jack has some sort of roller guide system inside the casing on top of the car but I was a really young repair helper the last time I was involved with unscrewing one of those jacks on the cartop and probably had my mind on girls instead of learning the inside workings of the Dover IVO jack. Haha. Any description or manual on the needed repair is much appreciated. Thank you.

The rollers are the same ones used on Dover pickup assemblies. I blow back oil into tank with compressor, use a big chain wrench to remove and tighten back down on top section of jack . Do a good job using expando and let it sit over night to set.

Are the rollers mounted on the top end of the stationary piston?

Yes in a 120 degree pattern. Hang the car sling approximately where the joint of the jack will be even with the top of the piston. Hang it on a couple of come-alongs so you can move the sling up or down a few innches.

Thank you guys.

The rollers on the piston are indeed the same size and shape as the door drive and clutch retractor rollers. However, they are made of a different material that is much more oil resilient. They are supposed to be blue in color. The door drive rollers are red and very firm. The clutch retractor roller is black and very soft. The black rollers will quickly disenegrate. The red will last longer, but run rougher. The blue will give optimum life and smoothness in ride.

Ok, thank you slider. I'll get them from Vertical Express.

Looking to get a copy of the Dover IVO installation manual for the holeless hydro. I have not been able to download same from this site. Working with a project that is reported as "jack guide rollers have worn a groove in the jack casing." The noise in the 'up' direction is loud; however, limited noise in the 'down' direction. Thank you

When you change out the rollers, look and see if the piston is centered in the cylinder. If not, adjust the piston platen on the floor to center the ring up, or you will prematurely wear out the new rollers