The engine originally ran a 181 style upright type 1 fan shroud but in a bus this is not efficient enough. The original type 1 cooling system is also not designed for high revving motors and the design of the fan itself is aerodynamically inefficient over about 5,000 RPM. In fact the fan actually stalls!. After Dyno testing with the fan belt on and of it was revealed tha the fan was actually sapping 22.5BHP from the motor!

the Porsche style fan shroud is a far more efficient design delivering more cooling, a larger, higher ampage alternator and sapping significantly less power. 

The engine starts out like this

Engine with original fan

first to come off is the fanshroud. disconnect the throttle linkage and the dynamo strap and remove the tinware screws. The picture shows the type one style upright oil cooler, not too much cop at keeping a 200bhp race motor cool. Also to be removed is the generator pedestal/oil filler. This will be replaced with a much shorter unit which will hold the porsche alternator and fan. An adapter for the oil filler will be added to the side in much the same position as the existing one.

Engine with no fan shroud

then off with the manifolds and the oil cooler. The oil cooler will be replaced with a blockoff plate with in and outs for an external oil cooler. In This application there is already a Mesa oil cooler with a fan under the bus. A second cooler will be run in line with this. The existing thermostat in the block being used to allow flow to the two coolers and the existing thermostatic switch will be used as it is to control the electric fan on the second cooler. 

Engine with manifold off

Then off with the cylinder head tinware and we're ready for part two, installation!

Stripped engine

[to be soon as the fan shroud actually turns up !]

Read part two here