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Project Marina, Finalising The Brakes

Finally, it’s been a long time in the making, but for the first time in many years, the Marina has brakes.

In the previous post, I refurbed and reassembled the rear brakes, but in the meantime I had also been working on the rest of the system. Unfortunately, things like this take time and money, both of which are a sticking point for me at the moment (mainly time, I’m waiting over a month for parts from the UK).

Even further back I started to strip the front calipers, which after some creative work with my compressor, I managed to do. First, I reinstalled the old pads, with a pry bar between them and used that to restrict the movement of the pistons, whilst pressurising the caliper and tapping the caliper body with a hammer. Eventually the pistons moved a little, but what made the biggest movement was using a punch and hammer to drive the piston out of the bore. Obviously, this is super destructive, so don’t do this to pistons you want to keep (but pistons you want to keep shouldn’t be stuck like these)

Out came one piston, along with a lot of sludge

This allowed me to slip the old piston back in after greasing it up, and using it to block the bore, and drive just the other piston out. I tried clamps, but there wasn’t enough space with what I had, so ended up using a hose clamp to keep the piston from moving.

It worked a treat, and I ended up getting all four pistons out of the calipers in this way.

Now, before I go further, heed my warnings. Playing with hydraulics, compressed air, and brake fluid, is a dangerous game. Make sure you wear all your PPE. If it’s not the crushing force of a piston flying out, it could be pressured brake fluid spraying into your face.

I should know, at one point when forcing 100+psi into the caliper I ended up with a fine mist of brake fluid spraying into my face. Thankfully I had safety glasses on, which stopped me from taking an eyeful of brake fluid and being blind, but it still wasn’t pleasant. I have now upgraded to a full face shield for work like this.

As well as spraying my face, I didn’t realise the fluid had travelled a meter or so behind me and ended up on the front of the Honda. Unfortunately, this sat on the paint and headlight overnight. The paint seems to have survived with only some minor marking, but the headlight has stained badly and will need replacing.

So yes, take care of yourself and your surroundings. ALWAYS wear the correct PPE. Also remember that plain old water neutralises brake fluid, so that should be the go-to for cleaning it off. Hydraulics are dangerous, if you aren’t confident in what you are doing, seek professional support for the job.

Anyway, moving on, this is why the pistons were stuck. Deep corrosion.

After scrubbing the calipers in the parts washer, they spent a couple of days in the Evaporust bath to remove the rust.

They aren’t perfect, and I probably should have painted them, but at the end of the day they are clean, internally rust-free and won’t be seen behind the wheels.

I purchased a seal kit to suit the Girling Type 14 calipers as used on the Spitfire, PN GRK5005, which worked a treat. These Girlock calipers are almost an exact copy of the Girlings.

In went the piston seals, with lots of rubber grease. Make sure these sit flat, and arent twisted or pinched.

Next it’s piston time. The pistons I used are once again from a Girling Type 14, PN 516212. These are slightly different where the dust boot sits. The Girlock pistons don’t have a retaining groove, just a lip. The Girlings have a recessed groove. I figure since the seals I’m using are for the Girling, the Girlings pistons will be just fine (and to note, the old Girlock seals are visually the same). The overall dimensions of the piston are the same. Girling on the left, Girlock on the right.

The Girling piston had a much bigger lead in chamfer, which helps during assembly.

Pressing the pistons in was easy enough by hand. Lots of rubber grease, place it square and press it in with fingertips. Once it seats a bit, I used a long spanner over the face of the piston to push down evenly with both hands (one hand on each side of the caliper). It should go in with minimal force.

The dust boot is a prick. The inner lip sits in the piston recess, the outer lip just rests on the lip around the piston bore. A retaining ring holds it in place by friction. Getting this ring in place, without it pulling the boot off, took a few tries.

I found the easiest way to do it was to line the ends of the ring up so they are touching (spreading the ring open), and working from the back (opposite the open end of the ring) work it around the boot, holding it in place whilst you stretch the open ends of the ring into place. It’s hard to describe, and do, but will make sense after a few tries.

Two calipers with new seals, pistons and boots.

I cleaned up the bleed nipples, making sure they were clear (they weren’t), and refit the hard pipes. That’s the calipers done.

Next in the firing line was the front rotors. I measured them a while ago and they came out as more or less new thickness, and have no lips. I feel like they were replaced not long before the car was laid up. Because of this, I don’t want to replace them, that would be a damn waste. I was going to just send it, and use the pads to scrape the rust off them when it drives, but thought better of that when I had a good look. Crusty.

The best thing in this case was to remove the hub and rotor, and send the rotors off to be skimmed.

Before removing the hubs, I measured the runout in them. There should be 0.0245 – 0.1270mm play. This is to allow the bearings to expand when they warm up in use. Too tight and they will bind and fail. Too loose and they will wobble about and fail.

Well, the Lh side had this much play

0.185mm play. Quite a bit above the maximum allowable. I’m getting an awful lot of use out of my dial indicator with these old cars!

The RH side had zero play, not a thing. So both sides were set wrong. Glad I looked.

The LH side split pin was…. split. It’s missing a whole leg, and was only sitting in place. It also pays to loosen the rotor bolts whilst the hub is on the car, just in case you need to stop it spinning. The rattle gun did this with no effort.

With the hub nut removed, the whole lot comes off pretty easily. The stub axle looks in good shape if a bit dirty.

One hub with rotor.

As a matter of course I bought a wheel bearing kit, as the old grease looked horrible, and there were signs of wear on the outer bearing races. The outer bearing was an LM11949 and the inner was L44649.

The back of the rotor looks worse than the front

Unlike the TVR, the rotors on the Marina came off easily with only minimal tapping with a hammer. I drove the old outer races out with a hammer and punch and gave the hub a good clean in the parts washer.

The rotors were sent away to be machined and came back looking good. They could’ve skimmed a little more off, but I’m sure the pads will scrub them clean in no time.

Before the rotor goes back on, the new bearings were pressed into the hub. The new bearings.

The new race was pressed in with the old race, and a deep socket

The rotor was loosely attached. Note the markings on the hub reminding me the rotor bolts aren’t torqued. This can only be done on the car, using a long pry bar to lock the hub from spinning.

The bearings were packed and fitted, along with a new seal.

Before fitting the hub, I quickly swapped the old blocked front hoses for the new ones. These are Land Rover hoses, PN BR0764

And on goes the hub.

Set to the correct runout

With the caps and calipers fitted

Both hubs had the rotor bolts torqued down, so the markings were removed

The last few pieces of the puzzle were the master cylinder (which I sent off to be resleeved and rekitted), a new brake pipe from the master cylinder (since I damaged the old one removing it. A friend helped make a new one), and new pad fitting kit (in transit from the UK).

The brake master and clutch slave I sent away to be resleeved came back looking lovely. Nice new stainless bores, as well as a good cleanup. Won’t have to worry about these rusting up again.

Of course, I couldn’t just fit the nice clean cylinder to the rubbish looking firewall plate, so that got a wire brush and a coat of paint.

It’s hard to believe it’s the same master cylinder, and the same cap. I cleaned and used Araldite to fix the crack in the cap.

The pedals got new clevis pins, since the old ones had seen their share of work!

And finally, the brake light switch was tested

Which revealed that it didn’t work. The switch is easy enough to strip, these tabs on the side need to be pressed to remove the bottom of the unit and pull the guts out

How this switch works confused me for a bit. When you remove the top from the bottom, it actually moves where the internal contact is, and if you don’t spot it during disassembly it can be confusing. It got to the point I purchased a cheap replacement so I could work out how it’s assembled.

This is whats inside the switch, and how it came apart

As it turns out, as seen on this replacement switch, the U shaped contact goes under the two legs.

It’s a Normally Closed switch, so it makes a circuit when the switch is released. When the brake pedal is pressed it’s releasing the switch, which makes the circuit, otherwise normally it’s pressed in, which moves the U shaped contact away from the two legs. The spring sits under the U shaped contact which pushes it up.

The replacement switch was a bit cheap, so instead I cleaned up the contacts of the old one and reassembled it. It takes some fiddling to keep the contact under the two legs whilst you slip the base in to the top housing, but it can be done.

A test shows that when pressed, the circuit is broken

And released, it makes the circuit

The original Lucas Australia switch lives to fight another day.

The pad fitting kit finally arrived today, so I fitted the NOS pads, new shims and new pins. It’s a bit of a pain with new pads and new thickness rotors, its all very tight, but it’s there.

I then drew fluid through with a vacuum bleeder, until all three bleed nipples had clean fluid coming through. Then it was back to the old one-man bleeder to finish the job. The brake pedal is now firm, with good travel. The rear adjusters have adjusted up (can hear the shoes slightly dragging the drum), and the hand brake is working. Everything needs a good bedding in, but for now, everything is doing what it should, and there seems to be no leaks. I don’t know when it last had brakes, but it may not have been in this millennium.

Now all I’m waiting on is a clutch master cylinder, which is en route from the UK, and a drive shaft that will be on its way to me tomorrow from down south. Once they arrive, we should be good for a trip up the driveway. Excite.

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