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14th Annual SoCal Vintage BMW Meet 2021! “All couped up”

Registration is still open. Rally from NorCal is scheduled for Friday. Post your event photos.

SoCal Vintage is Here! 

Post your photos!

who wants to play "What is this and where does it go&qu


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That was a vacuum line that apparently a PO determined was no loner needed. I've blocked mine off because I have gone to a mechanical advance dizzy and removed all the smog stuff on my ' 75. I've done the same thing you show, only cutting the hose about 1" long and capping it down near the intake manifold. You don't need the long piece.

Bob Napier

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is the giveaway...

On the original factory air cleaner, there was a hose that connected the air cleaner to the valve cover breather nipple. Inserted in that hose was a small plastic nipple connected to a small diameter hose as shown in your photo. The other end went into the manifold also as pictured. It was part of the emission control stuff--at least on the earlier cars (this is the setup on my '69). It's apparent purpose was to draw oil fumes into the manifold so they could be burned, without them passing through and gumming up the air cleaner and carb.

If that vacuum port isn't plugged, it should be. Remove the hose and VERY firmly plug the port (also the one on #4 cylinder branch). Otherwise you'll mess up the fuel/air ratio and possibly cause a lean burning situation--with possibly disastrous results to your engine. Ask me how I know.


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