Unknown cylinder repair....

mrcaptainbob · Oct 24, 2016

This splitter cylinder retracts great, but has no energy splitting. Different valves make no difference. Must be the seals inside? So, I figured out how to remove the first part, but have no idea how to unscrew the collar ring. There are two set screw holes, but only one had a set screw in it. I'm thinking over the years that water may have gotten inside to the threads. How do I get that collar to unscrew? I do not have a pipe wrench THAT big! Weld a small block on it and knock it off that way? No idea the age or the brand of this cylinder.

wdchyd · Oct 24, 2016

Yes, The threaded cap on the left needs to come off......if no pipe wrench use an air impact hammer plus heat......

mrcaptainbob · Oct 26, 2016

Thank you, wdchyd. I'll work on it this weekend.

LD1 · Oct 27, 2016

Looks like there is a hole in the cap on the side, made to accept a spanner wrench. If you dont have a spanner wrench, start there with a hammer and punch or the air hammer idea.

But before all this trouble, did you put a pressure gauge on the system? Perhaps a 2-stage pump not shifting to low? Or a failing/weak pump. I'd spend a little more time diagnosing the problem before tearing anything apart.

mrcaptainbob · Oct 28, 2016

The two holes on the side of that cap are threaded 1/4-20. Only one had a set screw in it.I suspect over time water got in and may have caused some rust. I have not checked pressure with a gauge. I assumed it would be a loused up cylinder seal because a valve body change had no affect. The cylinder has full power in retraction, but very little in extension. Only enough to barely help along a heavy pull by hand. And there is leakage at the ram end, too.

mrcaptainbob · Oct 29, 2016

was wrong about those two holes. Not 1/4-20, but they are threaded. Anyway, I welded a a 1/2w x 1L x 1/4T to that collar. Would not budge. Put the torch to it for about an hour. Kept moving it around the perimeter. After a lot of serious hammering on that welded tab I did get it to budge about a 1/6th of a turn. Must be a better way. I'm open for suggestions. I've started checking for a replacement cylinder, as I don't think I can get this one open. One more thing...after giving up on the heat and hammer method I liberally sprayed it with PB Blaster. Will do that again in an hour or so and let it soak and keep smacking it. I think I need a hydraulic cylinder to get this hydraulic cylinder apart!