Clutch master cylinder re-build.

[Nissanman]

I couldn't find anything on the site to illustrate this so here are a few pics. concerning the M/C re-build using "Repair Kit For NISSAN 1600 311 SP311 1.6L K7762X". (The M/C is a Tokico 5/8" which is common to the 310 and the 311)

20250411_140042.jpg

The master cylinder was still working OK but was losing fluid into the cabin and engine bay at the firewall.
Clearly we had a hydraulic leak and the seal(s) were suspect.
The piston was removed and here are the component parts.
The two large seals that fit over the piston are of different profile so make sure you note that and replace like for like.

20250411_140907.jpg

I have laid out the rebuild seals in the same order to illustrate where everything goes.
You have to note which way the tiny seal on that pin on the LHS goes but it only sits correctly when you have it right.
Once assembled with a little PBR Rubber Grease all seems to be well
When I dissembled the seals from the piston the cabin side seal seemed to be harder than the engine bay side.
I guess lack of use had caused it to deteriorate and leak
Not a real hard job to do, but it does require good eyesight, dexterity and a vice to hold the item securely when re fitting the piston retaining circlip.

[Bwk2000]

Bookmarking this one.

Thanks Graeme

[DAC21]

I couldn't find anything on the site to illustrate this so here are a few pics. concerning the M/C re-build using "Repair Kit For NISSAN 1600 311 SP311 1.6L K7762X". (The M/C is a Tokico 5/8" which is common to the 310 and the 311)
20250411_140042.jpg

The master cylinder was still working OK but was losing fluid into the cabin and engine bay at the firewall.
Clearly we had a hydraulic leak and the seal(s) were suspect.
The piston was removed and here are the component parts.
The two large seals that fit over the piston are of different profile so make sure you note that and replace like for like.

20250411_140907.jpg

I have laid out the rebuild seals in the same order to illustrate where everything goes.
You have to note which way the tiny seal on that pin on the LHS goes but it only sits correctly when you have it right.
Once assembled with a little PBR Rubber Grease all seems to be well
When I dissembled the seals from the piston the cabin side seal seemed to be harder than the engine bay side.
I guess lack of use had caused it to deteriorate and leak
Not a real hard job to do, but it does require good eyesight, dexterity and a vice to hold the item securely when re fitting the piston retaining circlip.

So is your repair kit considered the "minor" kit? As it looks like you reuse your existing piston and your kit doesn't have the 95mm long spring like what comes in what I believe is considered the "major" kit?

P1050849.JPG

[23yrRebuild]

Great stuff Nissanman ! Thanks for your time and effort to share this....looks WIKI worthy !
Mike

[Nissanman]

Yes it is what you would refer to as the Minor Kit.
It was only AUD$30 whereas the Major Kit is quite a lot more
Unfortunately the Datsun Parts Manuals are not at all detailed in the re-build process.
I had both M/C's fully reconditioned over 10 years ago during the resto. and lined with stainless steel sleeves so that wasn't a significant area of concern.
I'll let you know how successful this exercise was after a shakedown cruise or two

[drieseck]

Excellent, well done, much appreciated.