That does not look like a 4-108 at all. Look for the serial
number and check with your local dealer. Perkins were basically marinetized tractor engines. Everything in the picture is backwards.
This quote is from an old boat
group no longer active:
To Identify a Perkins Engine , On the Early models 4.99 and 4.107 the engine number is located just aft of the tappet cover (on the lift pump
end ) , stamped vertically The First numeral will be 7 e.g. (700666 ) for a 4.99 . Or 71 prefix for a 4.107
This could be obscured if a C.A.V fuel filter
is fitted prior to the manual lift pump
After about 1975 +/- the late model engines, the number is found on-the block , on top edge of the injector pump
housing interface on the block. In this case the prefix will start with 99 , for a 4.99 engine . 107 , for a 4.107 ,& 108 , for a 4.108 engine Further this may also be followed by a letter U (e.g 108U9200 ) The suppliers of parts are . American Diesels or Your local caterpillar agent .