Slow progress on the rear shock absorbers. It turned out that both were well worn, the wooden friction discs being so thin that the protective rims on the blade like arms were nipped together and the arms themselves squeezed out of parallel. One shock absorber was extremely tight until freed off by cleaning the discs.
The Augusta friction shock absorber relies on a very strong coil spring to clamp the arms and friction discs, the degree of clamping being determined by a nut on the bolt holding it all together, the nut is locked by a split pin and therefore not readily adjustable. I struggled to find a means of setting the friction to an acceptable level because the springs on both shockers are so strong that the slightest compression of the spring virtually jams the movement of the arm. Clearly something is wrong, perhaps a previous bodge, as one of the clamping bolts, which should have a peg/notch arrangement to restrain the head of the bolt, had been swapped for an ordinary hex bolt and although one shocker had a spacer on the outer end of the boss on the body of the shocker which acts as the bearing around which the arm swings, the other did not.
I found when taking them apart or re-assembling them, a plate bolted across the chassis side of the cast base will hold the spring compressed so other bits can be removed or fitted. In place on the car of course the base is bolted to the frame so the spring is controlled and the arms can be detached if needed.
Looking through a box of Andre Hartford bits, it struck me that I could dispense with the Lancia coil spring and use readily available Hartford parts, along with a new centre bolt, a Hartford star shaped dished spring and a few other bits to convert the Lancia design to something of a Hartford which would be a much better option.
Pictures 155 to 157 show the original and replacement parts. A new bolt with peg to stop the bolt turning, a tubular spacer to replace the spring, a slimmer spacer (recessed to take a clamping nut to hold the bolt to the base) , the original Lancia dished washer, the Hartford star spring, the tension adjusting nut (with indicator needle) and finally a locknut. The recessed spacer is needed as it acts as the bearing for the outer disc and arm, the centre boss on its own being a bit too short. Note the tension adjusting nut has to be 28mm AF to fit the Hartford indicator arrow and also needs a short spigot on the inner side to adapt the 14mm bore of arrow and spring to the 12mm of the Lancia size bolt. The locating peg hole was drilled 4mm and the peg made from a short length of 4mm drill shank loctited in place.
The original wooden friction discs were under 4mm thick but after a bit of measuring I found that replacing them with 5mm material would work, although needing 0.5mm or 1mm packing between ends of the short arms where they are bolted to the base. With this the arms and discs are parallel and the protective rims on the arms are just slightly separated. Photo 158 and 159. I suspect the originals were about 4.5mm thick but that was not available.
The available wooden discs for Hartford shockers are of a different size to the Augusta version but I found a supplier who can laser cut 5mm oak to suit and these fitted perfectly. I have a spare set if anyone needs them. They need to be soaked in oil before fitting and the metal faces of the arms greased.
The shockers can now be adjusted simply and they feel to operate very smoothly with only moderate “stiction”. Now all I need is a visit to the welder before it can all go back together.
We know Lancia was an individualist but I do wonder whether the unusual design of the Augusta friction shocker had something to do with getting around patents?
Mike
