ESM clutch lift kit. -instructions

[philthehill]

The radius is not that sharp because of the canted cylinder.
I am using 7/8" radius bends where necessary but I have a pipe bender which has 3/4" radius formers.
I have never had problems with 7/8" radius's but I always use new Kunifer brake pipe which has not age hardened.

[Bill_qaz]

Your brake pipe must make a very sharp exit with a very small bend radius! What is the minimum recommended bend radius for brake pipe?

My rear brakes are also servo'd - I could lose the long servo to rear brake pipe and go straight out of the back of the brake m/c as originally built. That would free up a bit of room in a very congested area. Is it ok to have servo front brakes (discs) and non-servos on the rear?

Mine is servo to front marina discs and direct from m/cyl rear to rear brakes. This is how it was when bought. I have the necessary pipes and fitting to servo the rears but have never felt the need to do it as the brake balance seems fine as is.
Be interested if you do re-pipe, if you feel a significant difference in brake feel.

[philthehill]

I would have the servo operating on both front and rear brakes. That way you are balancing the brakes.
When the brakes are operated the rotational braking forces tend to transfer weight off the rear wheels so having a servo just operating on the front brakes will compound the problem.
I do not have a servo fitted to my Minor but have Marina discs fitted to the front and the larger Wolseley 1500 brakes on the rear. The brakes are nicely balanced and stop the car very well.

[ndevans]

I've got a JLH Ford based disc kit on the front with standard rear brakes, all servo'd. Never felt it to be unbalanced, I just asked because taking the rear brake feed straight from the rear of the brake master cylinder would make the crossmember area less congested. I will keep it all servo assisted.

[ndevans]

Haven't made much progress. I have been working up a CAD drawing of the arrangement of the clutch master cylinder, measuring as accurately as i can from the car. At this point, I believe I have about 13mm between the master cylinder ad the inner wall of the chassis leg, and in that space is the brake master cylinder pipe to servo as it exits the chassis leg. It's very tight. I have asked Automec to make up a new brake m/c to servo pipe for me with as sharp a right angle bend as they can manage, as close to the pipe BSF fitting as they can. The minimum distance from end of screw fitting to outside edge of pipe after the bend is 22mm.

2 questions. The pipe runs from a banjo union on the rear of the master cylinder to the servo. On a standard Minor, the rear brake pipe runs out of the back of the master cylinder banjo bolt that the banjo union for the front brake pipe attaches to. Can I remove the banjo bolt and union from the rear of the master cylinder and just put the brake pipe straight into the rear of the master cylinder? I think this will give me more room, as the bend in the pipe to the servo can start inside the chassis leg, then I can put another bend immediately on exiting the chassis leg, so that the pipe will have turned through 180° after exiting the master cylinder? I guess this hinges on whether the flare on the pipe end is correct for the inside of the brake master cylinder.

2nd question. On a standard car with mechanical clutch linkage, the clutch pedal attaches to the adjusting rod from a point inboard of the pedal, not directly under it. I think I will have to weld a piece of metal onto the lower end of the clutch pedal for the clevis to the clutch master cylinder rod to attach to. I can't see how else I can get the linkage to line up reasonably straight. Is that the modification that you made Phil?

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Long winded post, apologies, and I may add some photos if that makes things clearer!

[Bill_qaz]

I would have the servo operating on both front and rear brakes. That way you are balancing the brakes.
When the brakes are operated the rotational braking forces tend to transfer weight off the rear wheels so having a servo just operating on the front brakes will compound the problem.
I do not have a servo fitted to my Minor but have Marina discs fitted to the front and the larger Wolseley 1500 brakes on the rear. The brakes are nicely balanced and stop the car very well.

With weight transfer to the front the fronts can brake harder than rear without locking. I would expect more chance of rears locking if servo. Also the disc front marina like yours probably need more brake force. Mine is standard road going 1098 with standard rear brakes and suspension, it never exceeds 55mph. As i said i find the balance good, so leaving as is, but I have the necessary pipes and adapters if the fancy takes me to servo the rears.
Horses for courses

[philthehill]

As regards the clutch pedal - I have welded a piece of steel to the lower outer face of the pedal lever to allow the linkage to be as near straight as possible. You could bolt a piece of steel to the existing pedal to get it all lined up before the final weld.
The rotational forces acting on the chassis is one of the main reasons that I have moved everything possible i.e. battery, radiator etc to the rear of the car. It has to be remembered that the engine block in a Minor is in front of the front axle (if it had one) so the loading on the rear is light compared to a vehicle with the engine block behind the front axle (if it had one).
To achieve a balanced loading on the wheels I did way back move the engine to along side the driver but rule changes put paid to that. That is the reason I have a welded in replacement floor sourced from a very poor condition traveller. Thankfully the underside of the traveller floor was covered in old oil so was good to go. The rest of the traveller did not go to waste as the parts were distributed around my then local MMOC.

[svenedin]

Unless I'm missing something this is madness. I appreciate what the OP said about his wife finding the clutch too heavy. There are ways round this that are much simpler. Reduce the pedal return spring pressure by stretching it or fitting a throttle retrurn spring bracket to the engine back plate. Overhaul the orginal mechanical linkage which may be very worn or fit a rose jointed linkage. For those interested these are rod-end bearings developed by Nazi Germany before WW2 for the the control surfaces of aeroplanes. In the USA they are still to this day know as Heim joints.

https://en.wikipedia.org/wiki/Rod_end_bearing

Stephen

[ndevans]

So I have got this far.

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New brake master cylinder to servo pipe fitted and clipped in at the master cylinder end. It just fouls the gearbox cross member, which is exactly as predicted in the CAD drawing that I worked up. This is not an issue, as I will be cutting a section out of the crossmember to fit the clutch master anyway.
I will mount the clutch master so that it's centre line is in line with the main "leg" of the clutch pedal, and use a suitably secured bolt to attach the clevis to. This gives me the offset I need to clear the brake pipe.
I need to tidy up, clip & re-route the servo to rear brake pipe, then cut the crossmember before I fit the clutch master and refit the engine & gearbox.

[philthehill]

Going through the cross member instead of going over the top of the cross member does not help. There is plenty of room above the cross member for the pipes to transit.
The same with the clutch pedal - plenty of clearance for the pipes to transit.

[ndevans]

The problem was getting the pipe to bend to clear the clutch master cylinder-the brake pipe exits the chassis leg right next to & slightly below the clutch master cylinder. That is why I routed it through the crossmember rather than above it-I wasn't happy about having to make a very tight radius bend right next to the existing right angle bend. Makes it more difficult to fit & remove the crossmember, but there are ways around that.
I also have the added complication of having the servo to rear brake pipe running in that space, which you do not have Phil. This needs to be routed close to the chassis leg in order to clear the clutch pedal and to provide space for the clutch relay shaft (I want to retain this in case I need to refit the mechanical linkage at short notice).
Edit:- Phil, are you running a standard Minor box? The gearbox cross-member in your photos seems to have spacers fitted between the chassis rails and the cross-member.

[ndevans]

Not much progress to report, losing light at 5pm and have commitments at the weekend does not help. I have got the clutch master cylinder in now.

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Haven't tried fitting the pipework yet, I have a feeling that I may need to turn the cylinder upside down to get enough clearance from the floor. Will that be ok?

[philthehill]

If you had angled the master cylinder away from the chassis rail as shown in my photo above you will have plenty of room between the master cylinder and floor for the pipes.

[ndevans]

I can't angle it the other way, the lower mounting hole in the cylinder is then right in the cross member semi circular cutout.

[philthehill]

See my photo above and you will see an additional plate attached to the rear of the cross member. I found it was necessary to fit the plate otherwise you are trying to attach to thin air.
You have to use a bit of ingenuity when fitting these kits and if needs must you deviate from the written instructions.
Most of the conversions on my Minor were carried out before the conversion kits became available so had to be thought through. Only the Mr Grumpy's Marina disc brake conversion is anywhere near to following the instructions that came with the kit and that was way back when Mr Grumpy was just outside Oxford.

[ndevans]

Latest iteration. I should have canted it this way in the first place, I just wanted to avoid having to cut further than I needed.

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Please ignore my scrappy attempts at welding the stiffening piece in. I was almost out of gas!

[kevin s]

when I did ours I cut a thick plate to carry the cylinder and welded that on the back of the ctossmember. allowing me to mount the cylinder lower.

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the bottom bolt is under the crossmember. This gives clearance to the pipes and floor. We do have a beetle dual circuit cylinder though which means the front pipe comes out inside the crossmember but at rougly the same height as the original.

I also ended up servoing only the front circuit after finding it had a tendancy to lock the rear wheels first on hard braking, thats with Vauxhaul Corsa front discs/calipers. This was also done on some production cars, Ford Corsair was like this and probably others.