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90q BVAU (tap tap tap Noise) Part II

I had a loud tap from the top of the engine(thought valves)...local audi
guy said it was worn lifters........... I was informed by a lister that
the Brake Vacuum Assist Unit, on the drivers side of the engine
sometimes made that noise.  I cleaned the unit but still had a tap in
cold weather.  Using my polish mind I turned out the retainer bolt to
the spring 1.5 turns, to apply more pressure on the plunger, which rides
on the camshaft............so far NO noise........Did I find something

Part II
This morning the tap was reduced to about one minute, from cold to I
hear it to its gone.  I got in there this afternoon.  ( life as a

I took the other end off.  The retainer bold is attached to a flat disk
which moves in and out creating the vac.  This travels in a oil bath,
and is held in place with a~11mm nylon lock nut,  ( so I was wrong the
retaining bold spins freely) I turned that 11mm nut out a bit and it
seems to helps.  I measured the distance the retaining bolt stuck out
past the casting, I added 1mm to the total lenght.  So far so good, this
might need to fill up with oil so it might take a few minutes of
driving. (very small oil passage) 

Final note: temp hit 40 this morning, and slight noise from engine,  NO
TAP.   I think that I will remove the disk and add a SS washer to the
back of the disk to increase the spring lenght.

And some additional thoughts:
I think the gods provided three problems. one the cam follower is solid
material, and might be wearing, I think the tolerances might be too
tight,  ( this unit should have a adjustment system like valve
clearances, I cant figure out the gods thinking, no adjustment of
clearances on a wear item???????  )

Maybe all we have to do is get a new follower?  or figuer out how to
make this units clearances adjustable. Like I did. 
dose anyone know the lenght of this unit NEW?  Is there anything in
Bentely about this unit?
are they using the BVAU on a latter model engine ? are there any
improvment to its setup?
ARGGGGGGGGH, BMW would never do someting this stupid.......... but I
cant afford a IX so I got this.

BEAKMAN'S WORLD ON TOUR coming to your town soon

J. Kurt Bonk
353 Reno Street
Philadelphia, PA 19123
215 625 2661

16 Deer Run 
Big Flats, NY 14814
607 562 3351

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