Hydraulic cylinder diassembly - stuck piston

Hi, I was looking for some advice re: an hydraulic cylinder I was trying to disassemble. It was given to me and apparently came from a forklift.
The cap/piston of the cylinder appears to be held in place by 3 pieces of curved steel (picture an internal snap ring that's divided into 3 pieces) which sit into grooves in the walls of the cylinder and 3 bolts screw into flanges on the cap and push on the cylinder so as to pull the cap tight against the 3 curved pieces of steel. At any rate, I removed the 3 pieces and was able to pull the cap forward about 1" but no further. Any ideas as to why this won't move? Or how I can get it come out? I was thinking of pumping some fluid into the cylinder to force it forward in the bore - good idea?
TIA for any help you can give me,
Terry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Clamp the cylinder in a vice and use the rod and piston assembly as a slide hammer to drive the head out of the bore. Most of the cylinders of this style I have seen use a one piece ring to retain the head. I think yours may be broken and this may have caused deformation and is why the head won't come out of the bore without force. Steve
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 30 Oct 2006 12:56:35 -0800, snipped-for-privacy@gmail.com wrote:

Standard problem when rebuilding cylinders. At least the ones that use a internal groove to retain the gland. Best method is to first drive the gland into the cylinder far enough that you can grind the burr off the outside edge of the groove (it will have developed from the ring pushing against it). Then rig something up to pull the cylinder apart (this is the hard part for most people). I use my large vise (very large and mounted firmly to a large pipe buried 5' into the ground and attached to the roof of my shop) and pull against another pipe which also supports my shop with a come along. It will likely be difficult to get out even with this method. The reason is that the o-ring seal on the outside of the gland will get into the groove and try to lock the gland in place.
I've know some people in the construct trade to use two large loaders to pull cylinders apart. You might could work up something with your truck and a solid tie point.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
not many cylinders ever used the three piece retaining ring but a few did , what the other poster has said about removing the burr is correct , be careful not to get into the rod surface , you will cut the o-ring as you pull the gland past the groove , but you were going to replace that anyway
snipped-for-privacy@gmail.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
As always, I do not have relevant experience, but my suggestion is to find a hydraulics shop to do it for you. It may not be very expensive. I am fixing a lightly out of order Cummins A series diesel, it had a bad radiator (bashed in) and repair it at a radiator shop was only $40.
i

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thanks everyone for the input, I rigged up a couple of trucks and pulled it apart after grinding the burr down. Worked great! Again, I appreciate all the help.
Terry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.