Valve cover leaks...how long for gasket glue to take hold?

[pvanbavel]

The silicone gaskets have been problematic as they tend to squish out of place as the valve cover is tightened. Adding any kind of sealant to them adds an additional problem, as there isn't much of anything that will stick to the silicone and you run the risk of having sealant flake off, go through the oil system, and plug the very small oil passages that feed the valve train and crankshaft. The rubber gaskets used on the oilheads, camheads, and water boxers are rubber but with a metal core that retains their shape.

If your heads or covers have slight scratches or scars you can resurface the covers by removing the studs and true the covers using sandpaper adhered to a surface plate, using a figure-8 motion on the covers. Resurfacing the mating surface on the heads requires removing the heads.

Personally and FWIW, I find the newer BMW valve cover gaskets to be more prone to leaks. You can always do as I have on my R80ST, and cut your own gaskets from sheet cork material sourced from a local NAPA. I adhered the gaskets to the valve covers and have had the same cork gaskets in use for the last 10 years or so.

Best,
DeVern

I'm wondering also if BMW changed their oil formulas.. not sure, but it might now be synthetic. Perhaps more prone to leakage?