BMW 3-Series E46 (1998 - 2005) - 02 2.0 Piston/valve clearances

Honest John Back Room » Technical matters
View Threaded
Thu 19 Mar 2009 18:11
02 2.0 Piston/valve clearances - paulc924
Ideas needed please. I have a damaged 320d engine to repair for a pal. It has suffered a mashed piston and head indentations due to the ingestion of a metal intake manifold vane. The piston protrusion has been measured so that the correct head gasket can be provided and the head will be skimmed. This leaves me with a problem. Although the head is flat, the valves are slightly pocketed and will therefore become closer to the piston when the head is machined. I usually put a piece of plasticine in the combustion area to confirm clearances during a dry build. My problem here is that the tappets are hydraulic and therefore I can't duplicate the true positions as in when the engine is in service. I have considered charging the tappets with air but air is compressible and the follower will not properly follow the cam. I have considered replacing a tappet with an adjustable rod to set the geometry but I don't think I will be able to take the gap up correctly when in position. Any thoughts please? Regards.
Reply | Report as offensive | Link
Thu 19 Mar 2009 18:39
02 2.0 Piston/valve clearances - Woodspeed
Grind down the tip of the valve stem? Just a thought.
Reply | Report as offensive | Link
Thu 26 Mar 2009 18:15
02 2.0 Piston/valve clearances - paulc924
Thank you for your advice but I will not be grinding the valve stems as they are often hardened to prevent wear and this would not result in the tappets being lifted to cause the rockers to follow the cam correctly. Thank you anyway. Regards.
Reply | Report as offensive | Link

Looking for a garage you can trust? Honest John's Good Garage Guide has thousands of reader recommended garages, plus how-to guides and tips on servicing.

The Good Garage Guide