Followers of this blog will already know I had Another disastrous weekend at Rockingham last time out keeping my 2014 race start tally zero. Issue one was another flywheel bolt failure for which I put a new clutch plate in and replaced with bolts from a reputable manufacturer (and torqued them up). After re-fitting the engine I then found air in the hydraulic clutch-line – and no matter how much I tried to bleed the system I couldn’t remove it.

This weekend I found the cause which was a pinhole fracture in the line at the point of the 90 degree bend into the hydraulic release bearing.

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I did think about building a flexible connection into the system with a bulkhead mounting on the engine / bell housing adaptor plate but in the end it seemed clear to me that the tight 90 degree bend was the real culprit so arranging the line with less sharp bends will suffice.

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I also made a clutch pressure testing tool so I can make sure the connection will not leak before putting the engine back in.

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So after putting the engine back in I have about 5mm clearance between the clutch basket and the clutch line. Too close? I’m not too sure but I might adjust the position of the line next weekend just to be safe.

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Thinking about this failure, I believe I have replaced or modified just about every component on this car now and I must admit 90% of the time once modified the problems do stay away so I’m confident I’ll get a race start at Silverstone.