Negative balance
Engine expiry presents an interesting fiscal dilemma
It was all going so well. With our Winter Warmers’ road trip to Yorkshire just around the corner (see page 66), almost every part of the Saab had been replaced or refurbished - except for the engine. It had been dormant since 2012 so with care, we slackened the fan belt, pulled out the spark plugs, replaced the oil and spun the engine over.
With some gentle coaxing from Tomkins, the engine fired and we stood back as it settled into a gentle thrum. All faces at the workshop broke into a joyous grin. We let it run for a few minutes, switched off and cracked open the tea bags. Celebratory supping commenced and I fired her up again. Our faces dropped. This time, a cylinder was missing and the thrum of that V4 had become a horrible chugging cacophony.
Luckily for me, I’m surrounded by some seriously skilful people and a range of expertise from the ever-helpful band of Saab enthusiasts, many of whom swear by the Ford-based V4. Engine bay access is tight though, as we were to discover.
How it went V-shaped
A methodical mechanical rummage throughout the engine bay revealed a lack of compression in the missing cylinder whilst subsequent rocker cover removal revealed a dislodged pushrod and a valve, which had stuck open after seizing in the steel guide. A head rebuild was inevitable so friend of PC James Jefferson was called in to do the job. Both heads were stripped and thoroughly cleaned and with very little effort required to compress the valve springs, replacements were ordered along with a new valve. Fine abrasive was used to clean corrosion from the valves and guides before all the valves were lapped in. Unfortunately, a common V4 problem came to
light after reassembly: the balance shaft bearing. Grasping the pulley, there was at least 3-4mm of movement.
As with many an engine, regular servicing is vital to a V4 - an engine with a number of known foibles. Fibre timing gear might provide smoother running but it becomes cheese if it’s neglected. If the bearings ‘pick up’ and momentarily stick to the balance shaft, it can shed its teeth into the sump and catastrophic timing failure occurs with mashing of valves into pistons.
So what on earth was a Ford V4 doing in the 96 in the first place? The two-stroke’s days were numbered by the Sixties, Saab having used it since the launch of the car back in 1949. Despite toying with the idea of using BMC’S 998cc A-series, a 1300 from Triumph and a Lancia V4, Ford’s engine – as used in the Taunus and German versions of the Consul, Capri and Transit – slotted straight into the V-shaped hole and was deemed to be more than tough enough. At least, it seems we’re testing that theory more than five decades later.
Back then, development was done with strict secrecy and only seven people aware of the V4 project, Saab engineer Rolf Mellde snuck off to Italy in a prototype and having returned with a list of required improvements to the unit, the thumbs-up was given for fullscale production in 1967. Five years later, when my car rolled off the line, the V4 96 was selling well and was proving to be a dependable workhorse worldwide.
Sadly, my particular car was proving to be anything but dependable. It’s a demoralising moment when you realise that no matter how prepared you are, absolutely nothing is going your way. But we’re not ones to concede defeat here at PC. It’s a machine and all machines can be fixed, right? Armed with a mug of tea and renewed determination, we stomped back to the workshop to plan our solution to this frustrating dilemma.
As I write these words, I have a Saab with a rebuilt head but shot balance shaft bearings and a bottom end in need of a total rebuild. And it’s a week before we are due to leave for Yorkshire. Replacement with a working lump is the only immediate answer. Now I need another engine.