Bleeding the brakes?

[fordson]

I've just spend a better part of an hour trying to figure out how to bleed the brake fluid from the brakes on my Z 5718 -73.
Where do I do this??

Also, does anyone know where I can find gaskets for the main brakes cylinders? Mine are totally shot and the brake fluid is just pouring from the container right through the cylinders.

Thanks / Jim.

 

[dave_peters]

Jim
Which country are you in ?
Europe/UK parts are readily available from Zetor dealers. Its probably better if you change both master cylinders for new .In UK at least, they are very reasonably priced.
Seal rubbers and pistons are available but given the age of the tractor the cylinders will probably be corroded inside.
To bleed the system you need an 9mm, I believe, box wrench and a piece of rubber tubing that is a snug fit on the bleed nipples which will be found on the top of the axle castings next to where the pipe goes in.
Fill the res. full with brake fluid, slacken one of the bleed nipples and put the rubber tube on it and put the other end in a container.
Un-link the brake pedals.
Pump the brake pedal that works the side you are working on and air will come out of the rubber tube followed by brake fluid . Keep checking that the res. has plenty of fluid in it!! An assistant is useful for this. When fluid comes out without air then get your assistant to hold the pedal down and you remove the tube from the nipple and do it up tight.
The pedal should then have non spongy pressure about 2/3rds
of the way down. Repeat with the other side brake.
Then when both pedals are pressed together they will only go down abour 1/2 way. this is normal.
Hope this helps, no doubt I will be corrected if wrong, its 25 years since I did a 5718. good luck
Dave

 

[fordson]

I can order the main cylinders and they are about 40 Euros each. I thought I would be "cheap" and just replase the seals but I guess it's best to replace the cylinders. Thanks for your reply.

Question: I was out on a field when the pedals lost pressure. The only thng I had with me was a bottle of servo oil. So...that's what I put in instead of break fluid. it worked, the brakes (at least on one side) got pressure and I finnished my work. A couple of days later the seals where totaly gone. Was I complete moron to put servo oil in?

 

[dave_peters]

Jim
It got you out of trouble, but has created a whole lot more. you will have to flush out the entire system and you may have to remove the slave cylinders and re rubber or replace them as well.You won't be able to get all the oil out of the cylinders without taking them off and this necessitates taking the axle housings off to get at them.
I had a crystal that had had diesel used instead of brake fluid and we had the same problems. However when its totally rebuilt at least you should be able to look foreward to several years without any trouble.
Dave