Morris Minor Owners Club

I need to replace my Master Cylinder and have seen some that have been relined with a st /st sleeve , Apart from not rusting are there any other benefits as they are about twice the price of a standard one. Or should I just stick to a standard one and save some pennies.

All advice welcome

Thank You

Alan

Where did you see them for sale? I have seen a firm that re- sleeves but you would need one to give them.
I like the idea of the sleeve, should aleviate the problem of the cylinder giving up when bleeding the brakes/ changing fluid.

http://srx.uk.ebayrtm.com/clk?RtmClk&u= ... 1368759off ebay .

A new one should be good for 20/30 years........is that not long enough for you??

gammy126 wrote:I need to replace my Master Cylinder and have seen some that have been relined with a st /st sleeve , Apart from not rusting are there any other benefits as they are about twice the price of a standard one. Or should I just stick to a standard one and save some pennies.

All advice welcome

Thank You

Alan

Alan, it is very difficult to get a smooth bore with even the most basic grade of stainless steel,an aluminium or brass or even steel tube is easy to get a polished finish on, SS will not have as smooth a bore, meaning potentially more rapid wear of the seals.
This has been my experience over many years with cylinders/rams of various sizes.
Difficult to see with the naked eye though.

Thanks for the link Gammy, I'll try the place I saw for a price comparison.

bmcecosse wrote:A new one should be good for 20/30 years........is that not long enough for you??

I thought we had mention on the site before about MC's failing due to the seals travelling further than usual into potenetialy damaged areas when bleeding.

Yes - after 20 or 30 years service............

I don't get 10 out of mine. Probably due another one soon.

One point to watch out for with lined master cylinders - whatever material the sleeve is made from: I've not got a drawing of a Morris cylinder in front of me, but I assume there are two holes between the bore and the reservoir. The one at the pushrod end is larger, and allows fluid to replenish the bore as the piston returns - the fluid flows past the main seal. The smaller hole only communicates with the bore when the piston is fully retracted, and prevents pressure changes in the bore due to temperature effects. The main seal thus slides past this hole every time you put your foot on the brake.

The problem is that this tiny hole - around 3/64" at a guess - is very difficult to drill once the new sleeve is in place, since you can't get a normal drill chuck through the filler cap. So some reconditioners make life easier by drilling a bigger hole, which, in time, rips the seal. The other problem is that most reconditioners can't be bothered to face the bottom of the bore where the top hat seal fits, presumably because most people wouldn't spot that their cylinder wasn't maintaining that slight pressure that stops the shoes retracting too far.

Kevin

Hi Alan,
You have probably had your Master Cylinder replaced by now, but I have had my Series II for over 50 years, driven daily. I had my Master Cylinder and Wheel cylinders sleeved with stainless steel more than 35 years ago, and have never had any fluid loss, or worn rubber boots in all that time. I am in Adelaide, Australia, and the re-sleeving was done locally. The price has been forgotten, but would hardly be relevant after all these years. I would suggest that you would not regret having this done. .....David

Just use the standard master cylinders, these are fine. No need at all to pay two or three times the cost for the same item just because it has stainless steel in it!

chickenjohn wrote:Just use the standard master cylinders, these are fine. No need at all to pay two or three times the cost for the same item just because it has stainless steel in it!

Amen to that!!!!