Here are photos of an aftermarket slave cylinder from my parts shelf.

I removed the actuator rod for this photo.

What I don't see in your photo is the bellows to hold the rod in place.

2 hours ago, Wally said:

a round black cap inset. its right below rod in image attached

That's the piston with the rubber seal.  You want to remove that and clean the bore and make sure the seal is not damaged.  There is a spring behind it.  You might have to blow on the fluid inlet, under the green cap (red cap in SteveJ's picture), to get the piston to pop out.

Here's the factory parts.  Aftermarket might look different but the general shape will be the same.

15 hours ago, SteveJ said:

What I don't see in your photo is the bellows to hold the rod in place.

I have it....just not in image. I got cylinder installed. As EuroDat predicted there was an issue with threads. I had to remove adjustment but and put it on the outside of the fork to get it to fit. Thus, one nut on each side of the fork. Even backing the nuts all the way down i could not get it to fit with both of the on the same side. Its jerry rigged but it appears that it will work fine. i can upload an image if needed. I haven't bled yet but all looks good for now. Hard to measure exactly with my digital micrometer but it appears movement is definitely b/t 10-12mm like recommended in this thread.

my only real concern is when i put this in all tightened up, something happened. It felt like the rod broke through that inset, round black cup a little (hope that makes sense?) It only went back a little though and not the whole way and it is moving good. Not sure if i should take it back off to re-inspect.

Edited January 19, 20223 yr by Wally

 I suspect the "round black cup" is a seal to keep the piston in the cylinder and is supposed to be removed before installation. I'd contact the dealer or manufacturer.

On 1/18/2022 at 1:39 PM, Wally said:

just got new clutch cylinder in.

From where?  What brand is it?

Can you post some photos of the new slave cylinder. I'm not sure I understand what happened: "It felt like the rod broke through that inset, round black cup a little" Maybe the piston seal was damaged when the piston was fitted into the cylinder bore.

 It's been a number of years since I was into a clutch slave cylinder but as I recall the rod pushes directly on the piston, not on a piece of black plastic.

 Its a Beck Arnley, whatever that is. Here is an image of it. I am going to take it back of and look back inside....better safe than sorry

heres an image of it attached. i took it off and took a photo too. that round "rubber cap" is not what i thought. it is metal and i think supposed to be there like that. So, looks like all is well.

The rod is put together wrong.  The ball nut goes on the other side of the release arm.  The lock nut keeps it from backing off.  They do not sandwich the arm.

11 minutes ago, Jeff G 78 said:

The rod is put together wrong.  The ball nut goes on the other side of the release arm.  The lock nut keeps it from backing off.  They do not sandwich the arm.

yeah. i know. there was not enough threads on the rod to allow me to back off both of them on that one side. I put it like this to see if it might work and keep me from getting another rod or trying to thread the rod more. 

It appears to still work even though its admittedly jerry rigged.