Front Master Cylinder - Reline or replace?

[mosto]

After many months finally got to reinstalling and bleeding front brakes after refurb.
Used the pgnz method and worked a treat thanks for the advice.
Thanks to you as well jones but would have been plan b if above failed.

[Jonesy :-)]

Mosto, I was going to write a 1000 words but went for a picture instead, rip out a valve and surrounding rubber from an old punctured tube and make one of these, an assistant will help, but guaranteed to feel pressure at the lever in a few pumps

[pgnz]

Hey Jones,
There was a rubber boot, although was perished so possibly the cause.
Also the bike sat for 14 year and all fluid was drained out.
The good news is it looks to have polished up well with a hone and steel wool treatment.
Have reassembled with new kit and at some time in the near future will hopefully get to commission and see if it holds pressure.
Thanks for your advice mate- appreciated.

Mosto, priming the brake system, simply
 master-cylinder/hoses/caliper circuits, nothing magic or complicated here whatsoever,
 quick and effortless with the right trick, no two-hour dramas of never-ending lever pumping
 and over-night tying of lever with zipties and re-doing over and over and all sorts of other
 BS ..   1. Fill reservoir with fluid. 2. Pump lever a few times with caliper
 bleeders CLOSED. 3. Open the bleeders(8mm spanner) with lever pulled in, multi-tasking
 is needed lol..  4. close bleeders. 5. Few more pumps.. 6. (the trick) ..get a syringe with nicely-fitted
 4-inch approx length of fuel-hose (transparent is best but not a big-deal) stuck firmly to caliper bleeder.
 7. Pull lever in ,open bleeder, suck fluid thru with syringe. 8. CLOSE bleeder. 9. Swap to other caliper and do the same..
 10. keep up the squeezing and sucking thing.. Before you know it you've got it all sussed SOLID FIRM ZERO bubbles..
Top up reservoir along the way and don't worry about "wasting" syringes of fluid.. Sorry jonesy mate, shortest i could make it...  hehe

 

[mosto]

Hey Jones,
There was a rubber boot, although was perished so possibly the cause.
Also the bike sat for 14 year and all fluid was drained out.
The good news is it looks to have polished up well with a hone and steel wool treatment.
Have reassembled with new kit and at some time in the near future will hopefully get to commission and see if it holds pressure.
Thanks for your advice mate- appreciated.

[Jonesy :-)]

Hey Mosto
where the rust/pitting is, was there a very soft flexible rubber boot/dust seal? if that was missing might be why its rusty

[mosto]

thanks pgnz ands jonesy.
Have sourced some fine wool and a two prong hone.
On close inspection may be a bit pitted but will follow your tips and see how it comes up.
Worst case it will bypass, then will have to rethink.
Cheers fellas.

[Jonesy :-)]

Hey Mosto
What pgnz said but in less words.
Just clean it up and put a new seal kit through it

[pgnz]

it's aluminium, push fine dishwash steel-wool or suchlike down there and twirl/polish by hand for another 350 years of use, the rubber plunger is usual culprit, wears down/gets soft, get another one ebay or wherever, should last till around 2075...  let us know how it's doing then...
 

[mosto]

Rebuilding front master cylinder and looking for some advice. Bore has a couple of minor rust spots in it at the outer end. Wondering whether it is worth having it relined with SS sleeve or seek out a replacement. Anyone had a reline done and what did it cost?