Does anyone have a drawing showing a fabricated bracket for mounting a hydraulic master cylinder on a low frame chassis? I assume one must have been made available with the kits for converting to the Morris Minor one. I will happily start from scratch, but it would be useful to get a bit of a head start if possible!

The original brake pedal pivot is higher than it once was as a result of introducing a wedge. The Ruby pedal fouls the underside of the Speedex fibreglass bodyshell I have. It clearly needs some thought as the rod pushing into the master cylinder needs to be attached on the opposite side... again, I have some ideas, but would be very grateful for a picture or sketch of anyone's existing set up.

Realising there have probably been a large number of less successful (or downright unsafe) attempts to do this in the past, I'd be happy to receive any advice on what to avoid, except converting to hydraulics... we are already well on the way!

Location: Essex

I've attached some pictures of the Morris Minor based setup on my otherwise standard box saloon. The master cylinder has a bracket on the chassis rail which it sits on, with the push rod squeezing past the steering arm to the brake pedal. The entire setup is slightly crude, and although it could probably be improved I'm going to be converting the car back to cable brakes.

I'll try to get some better pictures when the light is better if you think it'd be helpful.

From the top:


The push rod attachment to the brake pedal:


The bracket looking from underneath:

No need Rupert, they are perfect.

The conversion from pull to push is simple and the mounting clear. I will look at lowering the pivot rather than trying to find a different pedal.

Thank you!

Location: Essex

Nick,
This article describes the Master cylider mounting plate and the mods to push rod and pedal.


Bryan

If I,personally had a car already converted to hydraulics I'd leave them on.
On a recently purchased special it has a Bowden cable system at the front and a compensated cable system at the back,which looks like it should work but the brakes are pretty useless and I am considering going to the trouble of fitting hydraulics (which means a lot of work to the backplates/stub axles ) to achieve some confidence if I needed to stop in an emergency.
Only downsides to them is if the car is stood for long periods they may start to seize,or they are possibly too good (I have them on another car) and can lock the wheels completely.
Nick ,make sure you use a large bore master cylinder,ie MM

Slightly off topic but I have a pair of wide (ie RN type) banjo axle halves that have been converted to take Morris Minor type hydraulic back plates. They don't have the backplates. Happy to swap them (only) for similar standard axle halves. Would been even happier if the swap was for standard narrow axle halves but accept that might be a swap too far!!

Steve

Location: North Yorkshire

Bryan... Fantastic! thank you.

I have a 3/4" bore universal master cylinder (I think it is a series land rover clutch master) which I will try first. I was considering using two, side by side to give adjustment on the front/rear bias, having replaced the front expander with one hydraulic rear cylinder (with oposing cylinders so one leading, one trailing shoe). The weight of my special will be considerably less than a standard saloon, so I don't think the loss of additional stopping power will be an issue (it resolves the bleeding problem too). I'm thinking a bias valve will be easier now, as the linkage from the pedal to two cylinders gets a little tricky and above all, I want consistent brakes!

Thanks to all three of you. I'm not a big fan of technology, I have a wind up watch, but access to information has never been so good!

Location: Essex

Not especially A7 but any new hydraulic master cylinder installation should be very very solidly anchored on the chassis with absolutely no margin for flexibility. I made the mistake once, I know!
If the car is nor used very regularly, yes, I know it should be, silicon fluid is a must. Apart from the price of the stuff no drawback with it.
Those were my 2 €cts !
Good sunday to everybody,
Renaud

Location: Windy Brittany

Hi, i hated the all-in-one master cylinder on my student days A35, and the corrosion shown in the pics above goes some way to explaining why. On the hotrod RK i needed more stopping power so fitted a set of hydraulics. The master cyl is an ali girling universal, can't remember the diameter, with a remote reservoir. The master cylinder is mounted in the end of the front cross member, and a lug is welded (by a VERY competent welder) on the bottom of the original brake pedal, making it a pusher. All lines are in black coated stainless braided flexi hose, which, with the unions etc were bought from the fabulously helpful Think Automotive. As with Morris Minors, a wheel cylinder seizes every now and again, but they are less than a tenner from my local factors, who also keep shoes on the shelf. Bleeding the front is easy as you can drop a backplate off and hold it nipple to the top. A hydraulic brake light switch is soooo much more reliable than the wire and spring type too. The back plate assemblies came from Tony Betts, and were basically good, though they did need a bit of fettling here and there to fit a high chassis car. Overall i'm very pleased with the system, as it will bring a 4 up RK to a halt from 65mph as quickly as the car in front.
Winston

I converted my Ruby to hydraulics, it was a lot of work, but well worth the effort, the brakes give full confidence that the car will stop - I can compare the brakes with my Uncle's Ruby, which has the standard cable set-up, mine is so much better.

The Morris Minor master cylinder is a good choice because it has a side mounting and can be readily fixed to a section of angle iron, 90mm x 90mm by 150mm long, cut to follow the angle of the chassis, so that the mount is parallel to the centre line of the car, I bolted my bracket to the underside of the chassis, using 6 bolts, 3 each side of the flange, more professional looking than on the top (as is suggested in the notes shown in the advert in the above post). The underside makes for a very stable mount.

Here is my pedal operating pushrod, this I was given, it is a bit crude and could be improved upon but it does the job.

If you wished to go dual circuit, there is a similar master cylinder to the Morris Minor, available from USA, is expensive, mostly due to shipping & import duties, but does allow for splitting the front/rear brakes, I have yet to fit this!





These photos were taken some while ago now, during restoration, the car has been on the road for a year now & has done over 1,000 miles and I have been very pleased with the results!

Location: Saltdean, Brighton

In 35 years of using silicon brake fluid I've not had a wheel cylinder seize. I'm not surprised that cylinders seize using standard brake fluid, many years ago I changed the fluid (as per makers recommendation) on a car we'd owned from new I couldn't believe the amount of dirt that exited the system.

Here is the master cylinder I mentioned, from the USA, a very neat package, a variety of bore sizes are available, I got the one with the bore the same as the Morris Minor, stroke is about the same, so a good replacement. Not yet fitted, will allow splitting of the brakes into separate circuits, front & rear is the simplest, depends on how much extra pipework to fit!

Location: Saltdean, Brighton

that unit looks lovely. What would having two on one pedal mean in practice? more effort but tonnes more effective? And how does one manage/trimming the circuits?

My mini sourced unit is efficient but I think only just suitable when the brakes are very well adjusted - I could do with more volume shifted in the master. but wouldn't fit the Minor master cylinder which was considered an ambomination by the previous engineer owner. (Not sure why?)

Re silicone fluid, are there disadvantages too other than being more expensive? Can one just drain normal and refill silicone, or will that contaminate badly?

It's more a question of water. Glycol based fluid (Dot 4) is hygroscopic and the water it absorbs is what causes the piston seizure. A laid up vehicle is likely to suffer more as the pistons are siting idle and it is well worth changing the fluid regularly.
Dot 5 fluid is silicone based and non-hygroscopic but cannot be mixed with other fluids. Before using it the system requires a complete drain and I would suspect a flush as well. Seals may be affected and may also need to be changed.

Before you fit the system make sure all the seals in all the components are compatible with the fluid you choose.

Location: Ripon

One pedal. Bias often adjusted by having the push rod off centre between the two cylinders. This puts more force into one (the front). A single cylinder with a variable bias valve allows shifting on the go. You could also plumb in a hydraulic hand brake to flick the rear out and drit around corners. That must also require a front/rear split and for mot you need a separate mechanical hand brake too! Off piste? I'm not sure there is even any snow here?

I think I will stick with a single cylinder and a simple bias valve. My mates' MOT brake testing rollers can accommodate the narrow track of my Ruby so I can check everything is as it should be before braving the wild roads of Essex.

Thanks to all for the info.

Nick

Location: Essex

Hi Nick, if you e mail me I have a photo of the 'bench' mock up before I fitted the master cylinder. If it is Morris Minor master you have to make sure you have the correct adjustment. Details can be downloaded from their web site. I had to weld a piece on the brake pedal and then move the fulcrum point up and back. This gave me the correct adjustment. The master is attached the same as people have told you on the forum. I have a braking system which is as good as a Moggy Minor. Hope this is useful? Colin.