Z1OwnersClub GB

Hello everyone

My rear cylinder is leaking, in fact it is now empty, so I bought a new seal and piston and then removed the cylinder. I have obviously ordered some parts, at great expense that are not needed, as by the way the brake fluid has removed the paint, it has leaked from further up. As it is empty, I can only assume that it has leaked from between the alloy casing and the plastic tub.

Thing is, I have no idea how to remove the plastic from the alloy, is it threaded, glued, formed as a single piece in the depths of Mordor? Any ideas?

Richard



It's an A4 1976 Z900 with an A5 swinging arm and rear disc.

The plastic pot is threaded. put the whole thing in hot water to remove

The plastic bit is held on by 2 screws which are hidden under the plastic cover in the bottom of the chamber.

Once they are out, it just pulls off.

There's an o ring that makes it seal - but its not available from Kawasaki.

I have got a spare one that has been Xylon coated if you need one.

Cheers lads, I'll have a good look tomorrow and see if I can get it off without breaking it

TGreenfield wrote:The plastic bit is held on by 2 screws which are hidden under the plastic cover in the bottom of the chamber.

Once they are out, it just pulls off.

There's an o ring that makes it seal - but its not available from Kawasaki.

I have got a spare one that has been Xylon coated if you need one.

Two screws under the plastic cover, one mangled, so half an hour very carefully with a dremel got the little beggar out. I did have to screw the cap back on and tap it with a hammer for a while, but.....



How much would you like for it?

Richard

Richard, I got a couple. 1 Xylon coated and one not. If you can message me on whatsapp I can send you photos. 07736894268.

photos

TGreenfield wrote:photos

Cheers for the offer, but I thought you had an o ring

I'll give a rebuild a go first, so have found a suitable sized o ring.

Richard

Has anyone got a good source for that O ring, I have a NOS European spec Z1 master cylinder that has a weep from the joint between the plastic and main body.
Regards
Steve

wilsonsjw11 wrote:Has anyone got a good source for that O ring, I have a NOS European spec Z1 master cylinder that has a weep from the joint between the plastic and main body.
Regards
Steve

I got a 47mm ID, 3mm CS EPDM O Ring for mine, but it's a bit too big. I was going to get a 44m ID one, and try that, but I don't suppose anyone knows the correct size to save me guessing?

Richard

To finish this off, in case anyone has the same problem, there are two screws as in the picture below. I had to grind one of them out with a dremel but they are just M5 x 9.5 with an integral washer, so not hard to replicate. The aluminium plate holds the plastic cup in.



It still wouldn't budge with the screws out so I put the cap back on and gently tapped it with a hammer until it popped out of the alloy housing. I gave the whole thing a good clean up and made sure the inside of the channel which held the seal was completely free of any scale and muck. There was fair bit of crud in there to start with.



I got a 47 ID x 3mm CS EPDM O ring as that is what I measured it to be, but it was too big and wouldn't stay in the channel. So I bought a 46ID x 3mm CS and that fitted perfectly. The plastic cup is however a very tight fit, and easing it into place dry kept pushing the O ring out, so I used some red brake grease which didn't help much until I warmed the alloy housing with the O ring already fitted and then carefully pressed it back together. You can see through the plastic, just enough to see the O ring in place, to check it hasn't popped out.



Then back together with a new piston and seal, spending far too much time working out which that pesky spring fitted and working out a way of refitting that rubber cup onto the end of it. Big end goes in first with the smaller end and it's plate fitting inside the rubber cup. I ended up luckily finding a small metal tube with the same ID as the cylinder, and pushing the cup into it, then sliding the tube into the cylinder and pushing it from one to the other with a 3/8" socket extension,

I have sealed off the outlet, filled it with D4 to check it doesn't leak, and left it for week. No leaks so will chuck a bit of black paint on it shortly and refit.



Brakes all sorted



D'oh!