In November I read a post from an Engineer from Aston Martin he had noticed over the past year or so that during the strip down and rebuild of the DB7 Supercharged motors and some of the more highly tuned V8's and pepped up 'Old' 6's that there seemed to be a problem with water in these motors, there was rust deposits on the plugs and even on the upper parts of the cylinder liners.

He asked for help as he had performed every conceiveable test he could think of to check for moisture, gaskets...the lot...finally he had returned to him a motor that he had built not long before, it was one of the first motors he had seen with this 'problem'.

This mans qualifications and experience in re-building engines puts him in the top league, he has been flown all over the World to re-build motors for Museums and Collections etc. A man of exceptional skill.

He kindly sent me a Spark Plug from this motor asking if I would kindly check if the brown spots on it were rust and some huge exceptional quality photographs (his hobby) taken with his Hassleblad.

At first glance no doubt about it this engine had a leak, a water leak, not a bad one but bad enough, the odd thing was that apart from the odd hard race and a precautionary strip down and re-build, these motors would run beautifully.

But again that is no surprise as we all know that water can be injected into any engine and in all cases about 0.3% power boost obtained due to the thermal expansion of the water into superheated steam, even better in turbos because of that and the cooling of the charge prior to ignition.
Normally however the explosion and steam never leave a 'deposit'
on anything unless the chamber is 'saturated' and that is a waterway/head gasket failure....none of these motors had this!?!

The plug and photos 'screamed' gasket failure the engines were not using water at all and they ran smoothly, some had been 'cleaned up' and returned just a few weeks later to be found with this 'condition' not one fluid ounce of water missing from the system.

Under a 400× 'scope everything changed....the 'tell-tale' brown rust had become a complex chrystalline structure of great beauty and in polarised light this jewel of a structure flashed and sparkled in a manner that no 'full sized' jewel ever could to the naked eye...I recognised the characteristics immediately.....this was not rust.......this was Manganese.

(Big string section of an orchestra some where behind me goes....Da-daa-Daaaaaaaaa)

I now had a damned good idea as to what was happening.

I immediately made contact with our Engineer, who being a meticulous sort of chap had records of almost every detil of every spin of all the motors he 'owned' as he put it.

As he talked me through each car after about 40 minutes or so (yep, a telephone conversation that could have bored the pants off a frigid nun locked in a fridge in the middle of a frozen lake in the Arctic circle) a pattern emerged, all these cars had run Optimax and Octane boosters which is exactly as I suspected the moment I saw that chrystal structure.

Now I must emphasise that NO DAMAGE had occurred, a few very cautious owners had paid for a couple of very expensive re-builds.

This is why this thread has been revived..because almost all the contributors and many of the readers of this thread I believe are just that cautious and enquiring.

Moral..It may look like rust, it may seem like you are heading for a big bill, but if you use Optimax with a high Manganese Octane Booster then don't have a brown trouser moment, check everything first, perhaps a little less OB?