Z1 72-75 Master Cylinder - reservoir holes...

[MaineKZ]

So my 73 reservoir has one hole of about 2mm diameter drilled right through from the reservoir base to the piston chamber.
Beside this is a second drilling of the same diameter which stops short of the chamber.
I gather a much smaller diameter drilling continues down to meet the chamber ( intended to vent the upper part of the hydraulic system), but does anyone know what diameter this hole is? Must be tiny. I can't tell with the naked eye if there's even a drilling there, and when I poke around with a 0.25 copper wire it won't go down there.
So is there meant to be a hole there? Any tips on clearing it through?

[Rich]

Fuse wire will do it.

[MaineKZ]

Fuse wire will do it.

Thanks Rich. So it IS a hole then

What amperage fuse wire?

[Garn 1]

As Rich says, there is a hole and it is small. The fuse wire will need to be supported if used to be a probe for muck.

I use a carefully ground-down fine sewing-needle, held in a pin chuck. It's a lot easier to clear the hole if you have the piston out of the master cylinder, as it is hard to establish if you are not pushing the muck and the needle onto the seal. Hopefully the M/c it has been disassembled and you will see the needle end poke thru.

Don't know the size, however it's the finest hand grinding I have done. After seeing your project work, it will be a piece of cake for you!
RegardZ.

[DogsbolloxofZ1B]

Chris,
I've got some very fine drills and a pin chuck, I think the hole was 0.25mm from memory. The one you have of Grahams should have the same so if you or he bring it around I can check.

Mike

[MaineKZ]

Chris,
I've got some very fine drills and a pin chuck, I think the hole was 0.25mm from memory. The one you have of Grahams should have the same so if you or he bring it around I can check.

Mike

thanks Guys.

Mike - I'll give you and call - - cheers.