Monday 20 June 2016

Engine Assembly progress report

There has been great progress made on the engine rebuild by Superior Automotive Services.
The heads are now fully assembled, the new liners are in the block and the crank is fitted. It will be trial assembled (without rods/pistons) in a day or two in order to heat and water pressure test the block (ie the seal of the liners and fitting of ancillary water pipes) before disassembly to then fit the the pistons and connecting rods and final mounting of the heads.
Then of course assembly of all the ancillary components.

There have been a vast number of hours expended on rectifying little problems, to ensure the engine is as well set up as possible. An example being how many of the component mounting threads in the block were stripped or the old thread inserts had become loose, or even less simple things such as the thread depth of the head studs, which varied such that there were vastly different and unique thickness washers / spacers required under each head stud nut.

What Rodney and Brad have done (with much machining assistance from Crawford Hall) is to address these things so that the current rebuild gives the engine as best chance as possible to perform but to ensure that future rebuilds do not encounter these problems.

I have been unable to progress any further bodywork / rear suspension on the chassis assembly as I am still awaiting the return of the fuel bags with various problems / issues rectified, as the fuel cells must be fitted before other items. 

Proud Engine Builders

Rodney Gibbes (on the right) and Brad King (left). 
Proud BRM V12 race engine builders holding up the completed cylinder heads and with the assembled block ready for pressure testing in the foreground. 
A change from rebuilding those common garden Cosworth DFV and F5000 Chev engines.

We have learned an enormous amount about V12 BRM engines over the past 6 months. Whilst there is some similarity of components between the 'later' V12 engines manufactured by BRM, this engine has proved to be a bit 'unique', as confirmed by Rick and Dean at Hall and Hall.

Assembly in Progress

The photos below are the work leading up to the assembled state in the photos above.

Replacement of stripped threads or threads previously fitted with thread inserts that are loose 

Photo below relates to the varied depth of the head stud threads in the block.  
There are very few things in this car where the engineering was not completed well by BRM but the varied depth of the thread stud threads is one that they then addressed by having different thickness washers / spacers under the head nuts. Rodney and Brad have corrected this by individually fitting / sizing the head stud lengths so that consistent thickness hardened spacers may be used under all cylinder head nuts.

Final Assembly of Cylinder Liners into Block

Cylinder Head Assembly

Devil in the detail. The new springs were supplied with sharp unfettered tangs so each spring had to have it's ends carefully ground to remove this stress point. 


Measurement and checking of the height of each inlet valve.

Trial assembly rechecking of valve heights.

Photos below are with the head mounted, looking up from under the crank.
The first photo with the light illuminating exhaust valve ports and the second photo with the light illuminating the inlet valve ports.

Pistons / Rods

After the last trial assembly of the engine it was determined that some further material needed to be removed from the pistons to ensure correct clearance to the valves. The photos below are just doing a final check of depth before assembling the pistons to the connecting rods and the piston rings.