3c3 build 5 rear axle brake assembly

[ehannon]

Hi there,

A build 5 powertrain - is there a rear axle internal brake slave cylinder fitted?
I'm loosing fluid on one side and its not the master cylinder.
I'm hoping that it is a slave cylinder that i can change as opposed to a big axle job!

Many thanks

[essexpete]

There might be a workshop or parts manual that would include that axle on here under the slightly later early 3CX. We never had to touch the brakes on ours but the brake unit is in a separate housing from the main axle trumpet. My guess is if there is no obvious leak, then the internal piston seal will be leaking.
BTW don't use ordinary brake fluid in the system.

[ehannon]

Ok thanks for that pete.

Im hoping that the slave cylinder is external and it can be easily changed. Yes, im using mineral brake fluid, thanks

[dixie-normous]

Not sure of the properties of mineral brake fluid but i'm pretty sure the 3C3 uses hydraulic oil in the brakes, mine has a sticker on the dash saying to only use it

[essexpete]

Not sure of the properties of mineral brake fluid but i'm pretty sure the 3C3 uses hydraulic oil in the brakes, mine has a sticker on the dash saying to only use it

Yes I am sure that is what was used in our build 5 but the LHM type might be OK?

[agrimax]

Earlier build 5s had dry brakes.The last of them had oil immersed discs. If yours has dry,it will have slave cylinders on the top of the brake housings.JCB part no. 15/103600 for the cylinder or 15/103601 for a seal kit. Not so sure if the cylinder is still available though.Possibly superseeded...
If you have wet brakes,there are no outer slave cylinders,just an internal piston with a seal. Pt no. of the seal...813/00184.
10w light hydraulic oil or LHM fluid is the recommended stuff...

[essexpete]

Earlier build 5s had dry brakes.The last of them had oil immersed discs. If yours has dry,it will have slave cylinders on the top of the brake housings.JCB part no. 15/103600 for the cylinder or 15/103601 for a seal kit. Not so sure if the cylinder is still available though.Possibly superseeded...
If you have wet brakes,there are no outer slave cylinders,just an internal piston with a seal. Pt no. of the seal...813/00184.
10w light hydraulic oil or LHM fluid is the recommended stuff...

I had forgotten that, our wet brake had holes in the cab mat for the early dry brake adjusters. The dry brake set up must have been short-lived. We had a T reg here with a Brockhouse and our own build 5 was a V reg early 1980.

[ehannon]

Thanks for the information and part numbers - much appreciated.

Checked yesterday, my build 5 axle has wet brakes with no external slave cylinder - It has a large internal seal that is a much bigger job to do.
I will keep checking over it - hopefully it is something else before i have to go at the axle.

thanks again.