Engine rebuild update August 2007
The engine was been removed and after initial investigations, no obvious cause for the oil fouling was discovered. The engine was then completely dissembled and each major component has been ´flaw tested´.
Although all the major components were found to be okay, some of the crank bearings were very badly worn (on a 21K mile engine). After further investigation, it was found that one of the crank bearing housing/caps was slightly out of alignment!
This was inherent in the original engine block/machining and although not associated with the initial problem, will need to be rectified before the engine goes back together. Job is booked in with a local specialist machine shop for next week. The approach here is to machine the block and crank caps together to bring the true. This additional machining will then be compensated with oversize bearings.
Given this additional work, time is running very tight now for the Lotus event on 23rd September.
The general concensus regarding the oil smoke/fouling is that it was residual from the turbo failure and will have burnt-off in time.
Here are some images of the project minus engine:
Engine rebuild update February 08
When the engine block/crank bearing caps were machined, two of the caps were found to be very poor casting quality with breakthrough into airated material - these two caps are now scrapped. This will require sourcing of a full set of bearing caps for further machining. Although a set have been sourced, this means that it is practically impossible to complete the engine rebuild in time for the 23rd September.
This kind of casting quality problem is not unheard of and I´m very pleased that this was found now and not discovered during the autopsy of a ´grenaded´ bottom-end. I can only imagine the damage had these caps given out under full load.
Here are some images of the block and crank caps are now back from the machine shop:
The whole engine has been placed in the expert hands of a trusted race engine builder and should be assembed within by the end of this month.