THWARTED BY A FUEL GREMLIN
CAR: Alfa Romeo 8C
Run by Alain de Cadenet
Total mileage 150,230
Owned since 1972
Miles since February
Latest costs £50 (petrol)
For various reasons, FLC didn’t get much use during last summer. So, when an 8C Monza drive at the Goodwood Revival fell through, I had no option other than to nominate FLC instead. Short of time to prepare her properly, I paid most attention to the motor.
There’s nothing like a nice fresh oil change as you know – cheapest maintenance you can ever do for a car. I bought a 20-litre container of Extol 20w50 and added a couple of pints of Torco MPZ concentrate. Traditionally, flat tappet surfaces – as often encountered on overhead- cam engines – are in need of the lubricating properties afforded by the presence of zinc. Coupled with phosphorus, these two elements offer great benefit to an #8C-motor
, but they are usually lacking from today’s oils. Something to do with the environment, perhaps. The valvegear on an 8C is simple but effective, with Vittorio Jano’s version of the instantly adjustable tappet. The valves have the upper stem threaded (8mm x 1.25), with two grooves cut down the sides.
The actual tappet has serrations around the periphery and an 8mm female fitting that threads onto the valve. Underneath this tappet is another fitting with a larger diameter, also serrated, that acts as a locking device to stop the tappet self-adjusting while in use. Between the two discs are interlocking ridges that give a satisfying ‘click’ when rotated against each other. A special tool anchors into the hole adjacent to each valve and thus enables it to be rotated, either opening or closing the tappet clearance.
The 8C feeler gauge allows ‘Passa’ at 0.45mm and ‘Non Passa’ at 0.5mm. In fact, this is another process that is easier done than said because it takes me only about half an hour to remove the cam boxes and check all 16 tappets. Like all Jano engines, the valve springs are not stiff and the valves can easily be pushed open with your thumb.
Checking the differential housing for oil allowed me to let out a little EP90 and put it back into the gearbox, from whence it had dribbled over time. Quite normal. The diff mounting bolts needed a tighten, which they always do. I’ve been meaning to drill off the bolts and lock-wire them for 40 years.
Must do it next time, of course. Using this car spiritedly tends to wear the front brake linings, which allows the rears to lock up – especially the offside – so I undid the adjusting nuts two turns to fix that. The only other prep I had time for was to change the Blockley 500-19 tyres on the front wheels. I did this and the balancing myself because I have the use of a machine and have the right mandrel to fit the hubs. Anything under 20 grams out is excellent going for old wires.
The drive down was great – no trouble pulling 4000rpm in second and third. So I saw no reason why I couldn’t hit the revs in top. I have rather a lengthy crownwheel and pinion fitted to FLC, which gives 27mph per 1000rpm. Anything over 4000 at Goodwood would be good enough. Before practice, I put in five gallons of Lord March’s 110-octane rocket fuel to give me a little more advance on the sparks and tightened up the front friction dampers with my special spanner. The lovely Siata knob on the dashboard got three turns, too, which sorted the rear dampers.
Practice was a disaster. The motor wouldn’t pull over 3400rpm in top, although the handling and brakes were brilliant, plus the oil pressure and water temperature etc were fine. What little spare time I had to rectify the problem was spent believing that I had fuel vaporisation in the copper pipe down to the single Weber. David Biggins, with whom I worked on Sicilian Dreams, gave me the silver foil from his Naafi wagon bacon bap, which I wrapped around the fuel tube. This, surely, would cure the problem.
Idiot that I am, that wasn’t the fault. My race was spent trying to keep in front of Chloe Mason in her Aston Ulster and I couldn’t. I think I may have come last. Back in the paddock, I discovered that a tiny sliver of polythene had lodged in the float valve – starving the carb of fuel. So I picked it out. Problem solved. It pulled 4800 on the way back to London that night. Very boring because the next Brooklands Trophy race probably won’t be for another three years. Doubt I’ll get an entry after 2015’s effort…
Not so glorious Goodwood, when de Cad was stymied by the Alfa’s unwillingness to rev – traced to an errant piece of polythene in carb. Inset: slotted valve visible through tappet adjuster.
Alfa valve adjuster tool and feeler gauge. Valve is grooved and threaded for setting. It slots in and engages on ‘teeth’ of tappet.