Honing brake cylinders?


(Jim XK140 FHC) #1

Has anyone had success honing wheel cylinders ? I obviously want brakes 100% , but have also had poor experience of new repro parts and resleeving . I suspect mine are too far gone ?


(Paul Wigton) #2

Kinda a false economy: it’s brakes, so were it mine, I’d have them sleeved, in brass or SS.


(Roger King) #3

Interesting you’ve had poor Jag brakes, Jim. I’ve used loads of repro brake cylinders for Minis, Land Rovers etc. and not had problems. Some of those have been as cheap as £6 for a complete, ready to fit cylinder - how much are the Jag ones?


(Lee140FHC) #4

You won’t know till you polish it up a little to see just how bad any pitting might be. After, any black dots or specks represent pits.


(Rob Reilly) #5

New wheel cylinders for my Mark V are unobtainable.
I honed and polished them and they turned out fine.
I honed with the stones for awhile, then wrapped Scotchbrite around the stones and polished with that for awhile. They are a mirror finish inside.
I made stainless steel pistons and tops.
The rubber cups came from Napa Auto Parts.
PICT0003


(Phil.Dobson) #6

Jim I have used J &L spares with great success. They refurbished the cylinders on my 120
http://www.jlspares.com/index.htm


(Jim XK140 FHC) #7

I guess you are familiar with Britparts ? I had some £6 cylinders for my Landy, some lasted less than a year . New cylinders are £60-£80 each for the xk and I have read that some are 3mm too long so 6mm for the 2…
I would like to keep mine as I think they are original . I might experiment with a honing tool .I will get the other side off and see how they are.


(Jim XK140 FHC) #8

Thanks Phil I will get s quote and report back .
Jim


(Roger King) #9

In what way did the Britpart ones fail, though? Surely not the bores - more likely cheap seals, could be fixed with a decent rebuild kit if a leak is identified. Pristine cylinder bores are essential, so very careful inspection is needed. If they are too long but OK otherwise I’d be tempted to correct the length, depending on the part implicated. I’m not convinced I’d trust 63-yr-old brake cylinders - but I don’t know, I’m nowhere near brake renovation just yet so haven’t even looked at them.


(Peter Jan Rusch) #10

Hello,

I used new ones on my XK140FHC from SNGBarratt.


Perfect fit.

Regards,
Peter Jan


(Jim XK140 FHC) #11

Are those the same as the David Manners cylinders ? They look the same casting and the same price . If so I think they ar 1" bore rather than 1 1/8". They need replacing in sets of 4 to avoid uneven performance. It all starts to get awkward if straying from standard .


(Jim XK140 FHC) #12

I had 2 that started to weep , so I guess seals . If that gets on an XK shoes it gets expensive .


(Roger King) #13

With any new wheel cylinder, it’s always worth dismantling, inspecting and cleaning thoroughly before careful reassembly using the brake fluid you intend to use in service. It’s surprising these days how often you can find swarf etc. in them - but obviously that won’t help with manufacturing issues with rubber seal quality.
And please don’t use silicone brake fluid!


(Jim XK140 FHC) #14

Perhaps I am expecting too much that new parts out of the box work as they should !


(Paul Wigton) #15

That’s sooooooo… seventies!

:laughing:


(Gary Grant) #16

Hi Jim,
I have had good luck using one of those small brake cylinder hones powered by an electric drill.
I used kerosene to lubricate the hone to smoothe out all the pockmarks and scratches in the cylinders, then wrapped cloth around the hone and polished the bore of the cylinders to a mirror finish using metal polish.

Replaced the rubber cups with new ones from NAPA, and used DOT 4 fluid.

It took maybe an hour or two to hone and polish each cylinder, although it took a couple of try’s on the two worst cylinders which were pitted the most. Previously, the car had been sitting for 28 years, and all the brake pistons were stuck.
That was maybe 10years ago, and they still seal with no leaks.

Might be worth a try anyway. And thanks for posting your various repair videos…very entertaining and informative.


(Jim XK140 FHC) #17

I tried honing , mine where just too far gone . The stones where wearing out quite quick . I think if you need a quick clean up before polishing it would work well , but not for me . I will get them sleeved in stainless , about £40 each plus VAT .


(Paul Wigton) #18

Money well-spent, mate!