Blue Smoke and Increased Oil Consumption
01-84041 Blue Smoke at Idle and Deceleration Engine 102 Revised 4/86 4/84Increased Oil Consumption
Cause
Besides the known causes, such as the valve seals, valve guides, oil separator in the cylinder head cover, and piston rings, the following causes could also lead to the mentioned complaints:
Remove air filter cover and check if heavy oil deposits are present on the clean air side of the filter.
If yes, check the following:
a) All 102 engines.
Check oil return bores on right side of cylinder head (arrows) for free passage.
For this purpose, pour 1/2 to 3/4 liters of engine oil into the oil return bores. If the oil drains slowly or not at all, it is possible that the bore into the collection gallery in the crankcase is not bored or a casting skin is located in the collection gallery or the oil return passage to the oil pan.
Note:
The cylinder head of engine 102.983 has only one oil return bore at the right rear corner.
b) All 102 engines (except engine 102.983).
Oil is leaking between the washers and contact surface of the mounting screws (arrow) for the camshaft bearing caps via the screw holes. This can only be checked by removing the screws (arrow).
Check screw contact surface on camshaft bearing caps for nicks, scratches or other damage.
Remedy:
a) Remove oil pan and check from below if a casting skin blocks the oil return passage. If necessary; remove casting skin. If the oil return passage is not blocked, remove cylinder head and remove casting skin out of oil collecting gallery.
A missing oil return bore in the cylinder block can be drilled subsequently. Use cylinder head gasket as drill template. Bore diameter is 12 mm.
Cover up all bores and water passages and remove drill chips thoroughly
b) If nicks, scratches or other damage is present at the contact surface for the camshaft bearing cap screws, replace camshaft bearing caps.
c) Install oil separator with vent tube, part no. 102 010 01 062 (except engine 102.983). This oil separator is installed in production since March 1985.