Fuzz Townshend takes us behind the scenes of the latest series of Car SOS. This week, the Maserati V6 from a Citroën SM requires delicate shenanigans
There are a few cars that curdle the blood of even the leatheriest restorers. Telephones mysteriously disconnect and diaries fill with fictitious bookings, all to avoid cars which typically emanated from the minds of free-ranging 1950s and ’60s French engineers.
Perhaps sitting atop that fearsome list is the Citroën SM, with its attention-seeking Maserati 2.7-litre V6 engine featuring centrally-located valve timing chains, driven from the crank via a central shaft to which is attached the drive for the pump supplying vital pressure to the suspension, brakes and steering. Any untoward shocks from any of these systems can therefore be transmitted to said chains, causing them to twang, which leads to untold trouble inside the ill-placed power plant.
Seemingly, it was such a failure that had led to the SM owned by Car SOS nominee, Stuart, being taken off the road. Stuart had spent nearly two decades restoring his SM, a car that he had bought when in the U.S. and then transported home to the U.K.
The engine let go almost immediately on the car’s inaugural run, knocking the wind from Stuart’s sails and consigning the car to the back of the garage, squarely on the automotive naughty step.
The consequent internal damage to the Maserati engine was significant enough to require the extensive skills of the Ric Wood Motorsport team, which scanned and reconstructed the damaged areas of the aluminium block, as well as boring it out to accept a set of 3-litre pistons.
The latter process seemed simple enough, although fitting the new oversized steel cylinder liners into the aluminium block involved first removing a lot of internal material, and this left painfully thin walls between the cylinders.
Next came
