Restoration of a 1968 Citroen DS21bvh Pallas: Disc Brake Calipers And Final Preparations

This isn't very visual at all, as I was too busy to take any photos.

Re-acquainting the engine and chassis

The engine needed to be moved from my workshop into the garage. Not as straightforward as it sounds. A DS is long and with the car in the garage, there was little room to get anything through the doorway. Though believe me - having a little workshop next to the garage is so useful. Cue gratuitous shot of my garage......

Garage.... and workshop beyond

First of all, the car had to be moved back out of the garage to make the room needed to wheel the engine through from next door...... I removed the rear spheres and popped a couple of short broom handle lengths in the the rear cylinders to hold the rear suspension up.

Wooden rods used to prop up the suspension

With that done I was able to inflate and fit a couple of (very) old rear wheels/ tyres and remove the axle stands. I didn't fit the front wheels. I was worried that the rotation of the 'limp' drive shafts (no engine fitted yet) would tear my newly fitted drive shaft gaiters on the chassis. So, instead, I just raised a trolley jack under the beam that goes across the engine bay and used that to help move the car the three or four feet needed.

My home made engine stand was wheeled out of it's corner in the workshop. It had been in there so long. Years.

My homemade engine stand had served me well

My trolley had rubber tyres on it's castors and I'd found that the combined weight of the engine and gearbox squashed the tyres and made the trolley nearly impossible to move. That was one of the reasons I'd delayed fitting the brakes to the engine; to keep the weight down! With some difficulty and a number of 'three-point turns' I navigated the doorway to the garage. I felt like NASA moving a Saturn V to the launch pad!

Temporarily swapping places with my compressor, for the first time in many years the engine and car were back in the same room. With the trolley jack under the front of the chassis again, I moved the car back into the garage. In hindsight it was VERY high risk as the car could easily have fallen off that jack and damaged itself - if not me. As it was, I got away with it. The front of the car was put back on axle stands while I did the last few jobs to the engine. With tomorrow being the 'big day' when I planned to put the engine back in the car, those brake calipers had to be fitted......

Brake Calipers

There is a bit of a technique to fitting the callipers to the car. With the engine out of the car the brake callipers are fast and easy to fit. That's right: I didn't find time to take any photos...... I'll have to use some scrounged images.

The procedure for refitting the callipers is covered in Operation DX.451-1 in manual 518. Some PDF copies of manual 814, have a similar operation - Operation DJ.451-1 included in volume 2. Other than 'DJ' being for manual gear change cars, the basic process is the same.

The units should be bolted the car only hand-tight to start with. I must have fitted the discs over the half shafts, then slotted the calipes on. and calipers on I guess. But that really was all I could do at this stage. First scrounged photo coming up.....

The securing bolts are ringed

Until the engine is in the car and all the hyraulics are connected up, I can't finish the fitting: with the engine running, you need to get someone to apply the brakes. This causes the pads to contact the discs and (with the bolts only hand tight), the hyraulic pressure causes the calliper units adjust their position so that the pads contact the discs 'flat' and evenly. With the brakes still on, held on, the calliper units bolts can be tightened to maintain that position.

Making A Hydraulic Pipe (again)

I hadn't been planning to do this. In fitting the brake calipers, I found I had to re-make a long and complicated hydraulic pipe that went from the 'accelerated idling control' on the carburetor, all the way to the n/s brake caliper. I think it's the pipe for bleeding the left hand side brake. I've marked it on this photo.

The first one I'd made had been too short to reach the disc brake caliper!*! The pipe needed to curve around the parking brake caliper without touching it and that meant it didn't then reach the disc brake caliper with enough 'spare to be able to screw in the flare nut. It was short by about 2cm! I've used this photo before, but it shows the pipe in question.

The pipe around the parking brake caliper was too short!

The pipe follows a complicated route along the side of the block and was threaded behind other pipes so even more pipework and clips had to come off the car for me to fit it. It shares a securing sot with the 6.35mm pipe between the pressure regulator and the hydraulic pump. It's not wise to bend and weaken that pipe, so it had to be completely removed to allow me to work on this other pipe....As well as being difficult to remove (stop complaining Paul. It would be harder with the engine IN the car!), as I shaped the replacement, I kept having to do 'trial fits'.

Front Engine Crossmember

With the calipers fitted, I also re-assembled and fitted the front engine crossmember - the beam that goes across the top of the gearbox. The middle of the crossmember is a kind of 'sandwhich' with segmeted (castellated?) rubber half-bushes held to the main beam by two metal half-collars.

Front engine mount. The rubber 'sandwich' filling is parts 5 and 8

The middle section bolts to the engine/ gearbox and the rubber half-bushes in the sandwich isolates that bolted part from the beam that is bolted to the chassis. In that way, engine vibration and noises is kept from the chassis.

There are two brackets (numbered '3' in the drawing above) that bolt through the rubber 'daiblos' in the disc brake calipers. That also helps to absorb some vibration.

The rubber 'diablos' and bushes in the brake calipers

Why are they called 'diablos'? It's because the shape is similar to the prop you see jugglers used at circuses and is a kind of Chines yo-yo. No - really! Anyway, the only photos I have of those brackets are some last minute cleaning before repainting, but they look like this.

There aren't many pieces to the crossmember but they do only fit together one way: the engine doesn't sit in the middle of the engine bay and so the sandwich/ collar in the middle is 'handed' - it's not symetrical. If the collar is assembed on the crossmember the wrong way round, then when the assembly is bolted to the engine, the collar will not fit the curvature of the crossmember and it will be at the wrong angle......

Assembled wrongly.....(photo credit unknown)

This is how it should be.

Corrected! (photo credit unknown)

I was wise to this when I assembled mine - meaning I'm free to make a whole bunch of different and unrelated mistakes later on. And I'm sure I will! Anyway, this is mine (admittedly after the engine was back in the car). You can see the two holes that the radiator feet will bolt in to.

As well as the brackets providing the holes for the radiator feet, the left hand end of the crossmember also provides the location for bolting the LHM reservoir support to.