Kat 1000 master cylinder stripdown.

[bomberone]

Trying to strip the original masrer cyl that had shat itself over the fairing.  Removed the dust cover & circlip after modifying my pliers with an angle grinder. Then hit a brick wall. 

The manual says next remove the washer but it won' budge, even had molegrips on the piston with a slide hammer & tried tapping with a deep socket but no result.

It' as if the circlip was still fitted.  Any ideas?  Piston springing freely.

[hannibal]

I'm not familiar with the Katana master cylinder but the washer could be rusted/stuck in place. I had good luck by boiling the cylinder in a pot of water. Keep the lid on because the innards will go flying when the washer comes free.

[bomberone]

Nice idea using boiling water though I was nervous of damaging the flexible rubber seal in the cap.

Tried a bike pump & after much effort the washer released, but only the washer.  Tried some more & eventually a soft flexi seal released.  No further success with the remaining parts.  Tried boiling water but because the seal is leaking it doesn't build enough pressure.

Might try see if I can get a small drill down side of the piston to free the stubborn seal next.

 

[Dezza]

Try sticking the unit in an ultrasonic cleaner for 1/2 an hour.

[Swiss Toni]

Post a few pictures up! Once the circlip & washer’s out, if the piston doesn’t readily spring out, I just get a small punch/dolly, and tap the piston repeatedly back into the cylinder against spring pressure. Soon pops out!

As Dezza says, half an our in the ‘fizzy bath’ can’t do any harm. 

[Joseph]

Not being equipped with an ultrasonic cleaner and only having basic tools. I attempted what @Swiss Tonisuggests, only to see it get stuck deeper in the bore.

I ended up drilling and tapping the alloy piston and managed to pull it out with a long bolt that i screwed into it along with a bit of heat.

This was a common rear GSXR MC, so loss wasn't going to be much. Turns out the spiral groove of the piston was caked with sticky residue. 

Bearing in mind in my case rebuild kits contain all the internals it didn't seem like much of an issue to proceed via destructive measures for the piston, but i'm not a mechanic 

Classic boiling water with the lid on does sound good though.

[bomberone]

Ta for replies, might all be in vain.  Just looked on net for 1982 gsx1000sz front m/cyl service kit. Shows detail diagrams but 'No longer available'.

I'll have a hunt around.

[Wolf]

Air in revers of hydraulic flow usually does it but if a new piston is available drill&tap to pull works 

Newer M/C are available and if you more of a purist there are lookalikes 

[Wolf]

5 minutes ago, Wolf said:

Air in revers of hydraulic flow usually does it but if a new piston is available drill&tap to pull works 

Newer M/C are available and if you more of a purist there are lookalikes 

https://www.babbittsonline.com/oemparts/a/suz/50d3ccf2f870021958f282b3/front-master-cylinder