2021
There were a number of things still to be attended to before the car could be started and these were all done within the first six weeks of the new year.
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The propshaft had been already been reconditioned before the track test a few years ago. It had had a new centre bearing fitted, as well as new universal joints, and had been balanced. After refurbishment, the supplier painted the whole thing a generic black which didn't look good.
The propshaft was disassembled with markings where the two parts had to line up again. The rubber support was found to still be in good condition, so this was cleaned up and the steel components were plated. The aluminium centre bearing support was sand blasted and the propshaft was re-painted. The propshaft was then assembled and fitted to the car.
The radiator of the car was in a poor condition. The core was refurbished with a modern 4-core and deflector unit and while this was being done, I collected the header tanks. These were quite battered and I had to panel beat all the dents out of them, and being brass, it was pretty easy. These were delivered back to the supplier to assemble the radiator which was then painted along with the oil cooler.
The exhaust system needed some work. It had a lot of surface rust and the mounting bracket at the rear was poorly made. I made a new bracket and welded it into place. The exhaust was then brushed and sprayed with a high heat resistant paint, and installed with new hangers.
The tank came back from getting the fuel and breather connectors made, which fitted perfectly in place.
Two straps were made to support the tank, which were sent away for powder coating.
The bottom half of the tank was painted and then fitted to the car with the tank straps. High-density foam inserts were inserted between the straps and the tank.
The car was finally ready to be started. I was joined by my friends, who had been involved with the build of this car, specifically the engine and wiring system. (There's almost 200 years of experience in the picture below, with me bringing the average down to about 70...)
It was encouraging that the engine held all its fluids - that was a good start. With some coaxing from a tin of 'Quikstart' the engine burst into life.
As thrilling as it was to start the car and see it run, the car was not running on all cylinders. All cylinders were getting spark and all were getting fuel, but you could see from the spark plugs and feel from the exhaust manifolds that some cylinders weren't firing. The injectors were removed and re-checked, but they sprayed properly. The other possibility was that the fuel pump timing was out, and this would have to be checked.
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There were further issues to resolve. The brakes wouldn't bleed and even though the master cylinder was overhauled before the car was stripped down, the seals had deteriorated while lying on the shelf over the past few years. New seals were fitted to the master cylinder and the brakes now function as they should.
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The 'O' ring seals on the anti-dive mechanism on the differential had also split over time. These needed to be replaced, but needed the drive shafts removed for this to be done. It's frustrating having to do things twice, but while the diff was drained, I took the opportunity to weld tabs onto the drain and fill plugs to be able wire them together, as per racing regulations.
While bleeding the clutch, fluid started to run out the bottom of the gearbox bell housing, which indicated the concentric slave cylinder was leaking. The most frustrating part was about this was that the gearbox would have to come out again. This was done and sure enough, the slave cylinder was leaking.
The O ring seals of the slave cylinder were renewed and the gearbox was re-fitted. The system bled without much fuss and the clutch now worked, although the pedal was much, much heavier than standard and needed an assertive push to work.
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The car was now effectively ready for it's first test drive, but the misfiring engine needed to be sorted first. It was suggested that I check the spill timing on the injector pump, so I removed the injector pipes until number one was exposed. When I switched on the fuel pump, the fuel sprayed through the injector pump as expected, but once the fuel pump was switched off, air bubbles came from within the injector pump.
I phoned Rolf Frommjohann who overhauled the fuel injection system a few years ago, and he suggested I remove the return line back to the tank and see what was coming out of the line. When the return pipe was removed, nothing came out, so I started tracing the fuel line back to the pump to see where it was blocked. Eventually I found that the one-way valve at the back of the injector pump was blocked. It was removed and cleaned up and the fuel circulated back to the tank. This explained why the car was not firing on all cylinders: the air bubbles couldn't be eliminated and allow the injector pump to pressurize the injectors on some of the cylinders.
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The car was started and after a short while all the injectors cleared and the car ran clean on all cylinders.
Without using a timing light to check the timing precisely, the distributor was adjusted to find the sweet spot and the car was taken for its first test drive around the block. Manoeuvring out the garage and reversing up the drive way was a bit of a challenge and took some getting used to - the multipack clutch is a bit like and on-off switch. Nevertheless, the first impression is that the car pulls nicely through the gears and revs nicely.
The next thing to get done was the wheel alignment, and I drove the car to a facility about 15 minutes away from my home. It was the first relatively long drive and everything seemed alright, except that the car would not idle.
The wheel alignment made a huge difference to the car, but it still tends to track wherever it wants with the wide tyres over rough roads. The drive home was uneventful, but the idling issue remained. Closer to home I found that the brakes started binding and the clutch pedal needed a pump or two to change gear.
Once back home, I jacked the car up and found that the gearbox slave cylinder was leaking again, so out came the gearbox and it was sent in to be repaired. It was found that the concentric slave cylinder fitted was not up to the job, so a slave cylinder out of a Sprinter van was modified and adapted to fit, and this has solved the problem.
The issue with the car not idling, coupled with the fuel pump sounding like it was labouring, seemed to me a problem that we had had before. I removed the fuel return pipe at the tank while the pump was running and found that the fuel was only dribbling out, so somewhere along the line it was blocked again. I removed the one-way valve at the back of the fuel injector pump again, but that was in order. I then found that there was a blockage in the fuel damper deep down in the the V at the back of the engine and my heart sank. Getting this out would be a mission, but I persevered patiently and got it out, only to find that the one-way valve of the damper was blocked. This was sorted out and refitted, and the car idled properly again.
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The suspected the reason for the brakes binding was just an adjustment on the concentric screw connecting the brake pedal to the booster, so this was adjusted and the problem was solved.
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Of course this then warranted some more testing around the neighbourhood and the car did everything that it should:
As this car has been built to go racing without carpets and interior, I was concerned that the painted footwells would become scratched and scuffed over time. So I had a set of floorboards laser cut from 3mm aluminium sheet, and fitted them.
Some time ago I had an oil/ coolant catch tank made as per racing regulations. The tank is divided in two, where the coolant tank holds 1 litre, and the oil catch tank holds 2 litres. This was secured in place and the breather and radiator overflow hoses were connected to the tank.
The car was taken back to Rolf Frommjohan at TW Diesel to get the fuel injection and timing sorted out. All the linkages needed to be adjusted according to specification, and Rolf adjusted the fuel pump according to the larger displacement of the engine. When we collected the car, the difference was massive - the engine revved freely and the torque was astonishing.
An appropriate, and arguably the best tow car for the job, was found and put into service: a 1990 560SEL
