Primary Chain Oil Spray

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Revision as of 23:39, 17 January 2015 by Brodule (talk | contribs) (OOTFAB Dual Primary chain oiling holes)

The original design of the engine did not provide a direct oil spray onto the primary chain. This may have contributed to the early wear of chains. While modern chains are significantly more durable than those originally fitted, it is possible to add the spray that Citroen fitted to all later engines and required to be done on reconditioning. In order to locate the spray correctly, the following jig is required.


Use of a cardboard replica jig to show general location

An alternate set of spray holes can be added to the engine primary cover. See OOTFAB Dual Primary chain oiling holes

Picture of Spray Hole

Picture of spray hole (circled in white)

Spray hole is circled in white

OOTFAB Dual Primary chain oiling holes

Consider the simpler alternative of modifying the main oil passage in the primary cover to create two oil spray holes for the primary chain. Requires no modification of engine block. Requires only an angle drill and basic measuring skills.

Holes are located at at 2 o'clock and 7 o'clock facing the interior of the primary cover (10 o'clock and 5 o'clock facing the engine block). Holes are located 15mm back from the main oil passage mating face.

Spray Hole #1
2 o'clock
Spray Hole #2
7 o'clock

Drawings of a Citroen/Maserati-designed jig to locate a drilling site

Page 1
Page 2

Combined PDF: OilSprayDrillingJig.pdf

The original factory-specified hole was 0.5mm. Citroen specifies 1.0mm in this jig, possibly because of the care needed with the smaller drill. This 'modified from the original' jig allows the hole to be drilled without completely stripping or removing the engine.

OOTFAB made jig:

Drilling Jig
Drilling Jig

(See Marketplace:OOTFAB for more information)