Has anyone any top tips for removing the retaining ring on the master cylinder piston? Ive bought Brake Master Cylinder PS15 Brembo Rear Rebuild Kit. The intructions seem to show a circlip beneath the rubber seal but its actually a metal ring that must be an interference fit.
My question is does anyone have tips for removing this? When the piston is pushed in you get a better view but not sure how to get the thing out!
All tips gratefully received!
I seem to remember driving the whole lot out with a needle punch of 2mm diameter, through that little hole in the far end. When the new stuff goes in you need a extra long socket, something like 17mm, can’t remember exactly, I have used an old gudgeon pin, to use as a drift, from the other end. Whatever you use it must be a close fit in the cylinder to sort-of distort the washer-type thing and make it grip. Someone will probably come along soon with a better idea but that’s how I have done it in the past.
As mentioned above, drive the old piston out from the banjo end. A few sharp taps with a hammer will soon knock it out. I use an old blunt nail, it is not as if you are going to damage anything as you will be fitting a new piston any way. As for refitting the new ring, I have read a short length of 15mm copper pipe will do the job nicely, just push it home and it seems to click into place. Sure I pushed mine back with a screwdriver but a bit of tube or a long socket would be better.
The refitting of the linked master cyclinder piston etc requires a long thin walled socket .line up all the seals etc and tap the socket with a sharp smack with a hammer, metric hammer of course.one master cyclinder requires a 14mm socket and the other requires a 13mm but I cant remebemer which size fits where. the above is for a 1978 850T3 which should be the same as your bike.when removing the piston etc do not use anything with a pointed end as this might stick in the piston, use something with a smooth edge like a cut down Allan key. Thursday amJust had a look at a old linked brake master cyclinder and its the 14mm thin walled socket you require.
Thanks for all the advice, Ill give it a go, the next time I escape the house, thats under seize by 2 boys under 2!!
A 14mm slim wall socket and a 'leccy screwdiver with the tip cut off.
^ As above, think I used a bit of steel rod from B&Q. Need something firm like a vice to support the body while you hammer. To put new one in think I used steel tubing, but not sure.
Fab, thanks all! Got the metric hammer, the long stand, a tub of elbow grease, spare bubbles for the master cylinder and a bag of sparks for the grinder! Now slightly annoyed that this weekend away is going to put me into next week before I get near it! Excuses excuses! -HJB-2014-05-15 21:59:39
Do you need a new bubble for your spirit level? Will have to be a round one though ~ I did have a square one but I dropped it and knocked all the corners off