1977 BMW 630csi: H&B

M30 Dual Chambered Oil Sprayer Bar (DCOSB)

A semi common/lesser known issue is the oil bar on the M30 engines. several things can account for it.


  • broken loctite, you cant simply retighten and expect it to hold. once the loctite seal is broken it must be replaced. creating leaks and lost pressure.
  • over torquing the bolts and pinch the and bar and present leaks and or cracking.
  • “the front most cam lobe does not receive enough oil because of the lack of oil pressure in city driving. The long hollow OSB does not develop enough pressure at the front of the bar to oil the front cam lobe. Thus, the front cam lobe wears too quickly causing the M30 motor to run badly”

The DCOSB solves that problem by creating two pressure chambers to feed oil to the cam at higher pressure.  a detailed how to can be seen HERE.

This is a simple upgrade to perform that has long lasting benefits

I also purchased a banjo bolt kit from DON. it includes new cross drilled banjo bolts, sealing washers, lockwire, and very detailed instructions!bb-3

my photos:

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