2020

While restoring the inlet manifolds last year, some of the Bakelite spacers for the fuel injectors were found to be cracked and a few of them had been repaired with epoxy. These spacers are no longer available from Mercedes-Benz, so a local supplier was found who could re-manufacture these with CNC machines from Balekite sheet, and these were finally delivered early in the new year. 

The windscreen wiper motor had never been connected to the wiper mechanism since the manual pedal box was installed a few years ago and the next thing to be attended to was to connect the wiper system. However, once everything was connected, the arm on the wiper motor was stopping up against the pedal box. Clearly the manual pedal box with a clutch pedal was wider than the original automatic pedal box, but I wasn't sure what to do about it. I thought that maybe a pedal box from a W109 3.5 might work, but I couldn't think it would be any narrower than the one I had. I was left with no option but to remove the pedal box and modify it, and this meant the booster and everything had to come out again.....

Once the pedal box was out, the bump stop had to be cut off because it would have to be re-positioned. The clutch pedal pivot was then cut down to bring it closer to the pedal box, but it also needed to be ground away at the top to allow the wiper motor arm past it. 

The pedal box was reassembled and refitted, then taken out again and disassembled numerous times to get to the point where eventually the wiper arm cleared the pedal box.

The clutch pedal was now in the correct position, but the pivot for the spring on the clutch pedal was way off centre. The pedal needed to be cut and a right-angled spacer welded in so that the pivot lined up with the spring. Once this was completed, everything was sent for powder coating and reassembled.

During the pedal box modification, work continued on the assembly of the engine. The damper and pulley were painted and the timing marks were highlighted.

To do the compression ratio calculation, a measured amount of liquid was poured into the combustion chamber to determine its volume.

The bespoke copper cylinder head gaskets arrived from the supplier, but during the compression ratio calculation, they were found to be too thick at 2mm. Thinner gaskets of 1mm have subsequently been ordered.

The rear crankshaft rope seal was inserted into the engine block and with great care and patience, the crankshaft was fitted and slowly rotated and tightened to bed in the seal. Once bedded in and torqued down, it was found that the pistons were slightly lower then the face of the block at TDC. Everything has had to be disassembled again so that the block could be skimmed. 

The conrods on this engine are big and heavy, but strong.

Progress continues....