1986 SJ - Brake master cylinder

I have never had to replace one of these on any SJ/Jimny I have owned but I have been asked countless times about getting one that fits and works. It would appear that there are different sizes etc. and unsuitable aftermarket variants out there. 

Does anyone have any experience and recommendations before I go off and learn for myself how to get the correct one. 

P.S. brand new, not used.

 

Sorry never had any problems with them. But i have bought a service kit for these once, but never had to use it on the SJ. But when my daughters horse carriage had a stuck brake master i found that the gaskets and rings for the SJ fit the carriage master spot on.
It was an easy job to get all the oxydation out and make it shiny and fit the new seals..

Anyways my contacts here in the suzuki club should have no problem finding the correct part number, but you can do that as well I guess?

Thanks 

As a further question, the master cylinder I have is 13/16 which I assume is the "bore" of the cylinder. I can find a few SJ that are 7/8 (which is, of course, 14/16). Now apart from "1/16", is there any actual difference and do you think they are interchangeable?
 

I had an issue with my Jimny master cylinder and had a nightmare trying to find a suitable replacement or the correct parts to rebuild it. There seemed to be more parts available for SJs than Jimnys. I bought a rebuild kit that looked right but was the wrong size.
The bore affects the mechanical advantage of the system. Switching to a larger bore will give you less pedal travel but require more force on the pedal to achieve an equivalent braking force at the wheels.

13/16 is 20.6mm and most online are 22.2 (22)mm  
Edit: 14/16 is 22.2mm

when selecting the car in the shop no master cylinder comes up to select.

On my '84 reg number there are only the 22mm that comes up.

Tried my '87 SJ reg number in the part store today and got a hit.

In my euro pars store there is ASHIKA 68-08-807
wich has data as below:
(translated from NO to UK)

EAN:8033001725988
Internal thread [mm]:M 10 X 1
no of threaded holes :2
Hole diameter [mm]:20,6
Mounting diameter (mm):41
Internal diameter [mm]:35
Dist between mounting bores [mm]:95
qualitylevel:Budget
Producer:ASHIKA
Art. no.:68-08-807
strangely this one part is the only on with stated 20.6mm.

www.eurodel.no/hovedbremsesylinder-ashika-68-08-807
pictures too. I do not think it is the one though, seems wrong on the picture.


this on on the link below seems more like it I think:
www.eurodel.no/hovedbremsesylinder-ashika-68-08-896
but this one have lesser info and measurements.

Hope this helps.

part store also suggest several 22mm rep kits and the same complete master for the '84.
(wich seems to be correct for that car. it has no brake booster)

I would like to have in stock both 20.6 rep kit and 22mm, I'll see what I find next time byuing.

edit: I have noted there are differences in the layout of brake lines between different models of SJ's. Only '85 and on I seen with two brake lines going aft.
My '84 have just one going aft so the line go through the right cylinder to feed the left. 
And it is also the same on lwb '88 (samurai). I only had the lwb's
Not sure if it is the same on '86 and '87 here too i only have the lwb's
could this be linked to the different brakes? 
There are also a large variety in rear brake shoes on the SJ but the drums seems to be the same.
Funny though how the '85 have larger and wider shoes than a '05 Jimny (not the same drums)
but front calipers and brake pads are the same all years. 

As far as I know all the SJ413s have the same rear brake piping, a single line feeding the left rear and then across the axle to the right.

What you should be seeing is two lines (one front, one rear) that go down to a proportioning valve and from that one pipe to the rear.