oil leak

[mike24290]

Hi all
1977 Renault 4 L 782 cc
I have an oil leak above the pully driving the ancillary items ,have checked rocker box gasket not from there
although it doesn't seem to use water the exhaust steams a lot !
hope its just the head gasket !
any other ideas ?

 

[JdeW]

You´ve got a 839-06 (or 07) 782 cc Billancourt engine and these engines don't have an oil seal at the end of the camshaft that drives a pulley.
The sealing is done using helical machining (grooves) in the opposite direction of the engine rotation, the same for the crankshaft.
If there is a leak it is probably because there is too much play between the camshaft and the bore of the first bearing.
The clearance at the flange should be around 0.060 to 0.14 mm.
It is also possible that sediment has built up in the grooves, preventing oil from being returned, so cleaning those grooves could help.