I participated in my Mini Club's Rally to Maranda Hot Springs recently. We had to navigate our way to the destination using
notes provided and also answer questions. It was a good day, and dispite rather scrappy tyres on the front, I was moving rather
quickly. So quickly I faded the brakes completely on several occasions, luckily they brought my speed down enough that it wasn't
TOO scary when they stopped working. I was using 1275 GT calipers and road pads of unknown origin. The fluid in the calipers is
probably rather old, especially in the outside chamber. This probably contributed to the fading.
About an hour into the event, I was comming down a sight hill and lifted off for a corner at 6500 rpm in 3rd gear. Suddenly
there was a rather sick knocking from the engine. I declutched and the engine idled but still made the noise, I shut it off
and coasted to a halt.
It was a significant task to recover the car, as the AA wouldn't tow me home. Too far for that, and not far enough for my extra
cover to be applicable. Neil, a club member kindly helped me with a cheap truck to transport it home.
When I got it home, this is what I found:
Quite a mess!
The piston is worth more than NZ$200, the valve is probably $30-40, but the damage doesn't stop there. The bore has been badly
scratched where the valve has been caught between it and the piston. Luckily, this damage is all above the rings, however the
block needs to be planed. The head has been damaged in a similar way and will need to be planed also. The valve head got caught
between the seat and the piston and put some rather large dents in it. The seat will have to be replaced with a hardened one,
if it can be done at all. It may be that the head is a write off.
The valve is a genuine Cooper S valve, part number AEG 594 VL, aparently is it extreemely strong, however, it is also at least 30
years old. It is made in two parts, the stem is welded onto the head, and it isn't unheard of for them to seperate. You can
see the end of the stem jammed in the valve guide in the head.
The parts are at the reconditioner at the moment. Not much will be happening until I finish my exams, at which time I will
be rebuilding the thing with new, hopefully one piece exhaust valves. I will also put lighter valve springs on, as the current
set are good for more than 8000rpm. The flywheel is only good for the 8000 and the engine is beginning to run out of steam
at that speed. I would rather have less wear on the cam and other valve components than a high rev limit which I don't use.
The cam has some damage, though not on the lobe with the valve that broke. It has pitting on number 7 and number 2 lobes, so it
will be going back to the people that ground it for a regrind.
