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Old 06-08-2012, 08:47 AM
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bluebee bluebee is offline
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Mein Auto: 02 BMW 525i M54 auto 130K
Originally Posted by johnstern View Post
I drilled the holes through the outer AND inner layers of the dipstick tube.
I had wondered about that, even after having looked at the very nice picture set.

For each hole, did you drill straight through all (4) layers of steel?
Or did you just drill the outer (2) layers of steel on each drill pass?

Originally Posted by Fudman View Post
I believe your diagram is correct.
Thanks. The only thing I can 'think' of then as to 'why' BMW designed the concentric tubes in the first place, is that (perhaps) they didn't want the oil gunk condensing from the CCV vent to deposit uglies on the dipstick itself. That would 'look' bad when the dipstick is pulled out for inspection.

I can't think of any other reason for the expensive and problematic concentric tubes, other than to keep condensed oil away from the dipstick itself.

Originally Posted by Fudman View Post
the "tank" (oil sump) is just a container for the oil. And yes, the holes should not really matter.
Thanks. I realize these answers may be obvious to you, but I'm struggling with the 'why' of the concentric-tube design. It baffles me why they went to a huge expense to design a tube within a tube just so that the dipstick wouldn't get oil on it. I'm looking for the 'catch' in the redesigns ... the thing we may have missed.

Originally Posted by Fudman View Post
cut the outer section of piping
This makes sense. Eliminate the entire outer tube, if possible, at least where it can be eliminated and still have a mechanical fit.

I wonder if we can simply grind (or cut) the outer tube entirely away (leaving only portions needed for mechanical integrity & for the tight fit into the oil tank hole).

Originally Posted by Fudman View Post
it would not correct the limited flow through cross sectional area that still exists at the connection interface.
Understood. In fact, that little-tube-to-big-tube connection was jammed solid for me (right at the curve where the steel ccv vent connects to the steel outer dipstick guide tube) when I tried digging down from the ccv vent side.

Originally Posted by Fudman View Post
the improved dipstick tube is the best solution
What I absolutely hate is giving a $130 (times hundreds of thousands of BMWs) to the very same people who designed the abomination in the first place. It's rewarding BMW for failure. For example, I'd prefer to buy a Toyota dipstick guide tube (were it a fit) over a BMW-supplied "improved" dipstick guide tube ... just on principle (if it worked).

Originally Posted by Fudman View Post
I did mine 2.5 years ago and may need to redo this again
Since mine is not redesigned nor modified ... how long would you think I have before mine becomes clogged?

Since nobody probably has that data (depends on weather & driving style) ... may I ask whether the standard CCV tests can determine if your dipstick is clogged?

Since mine was clogged and I didn't know it, I'm sure thousands of others are clogged.

Q: What's the best (easiest) TEST of a clogged dipstick guide CCV vent tube?

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Last edited by bluebee; 06-08-2012 at 03:07 PM.
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