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Old 09-21-2011, 01:51 PM
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bluebee bluebee is offline
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Location: San Jose, California
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Mein Auto: 02 BMW 525i M54 auto 130K
For the record, we're still not done, because there is a very real danger that the Duralast 49-DL battery vent tube 'can' get pinched between the very heavy battery and the hard plastic protrusions on the side of the battery compartment.

That would be a very bad idea (see this thread if you don't know why).

So, by way of being excessively clear in a DIY, if you're going to put the 'wrong' battery (technically) into your E39, at least make sure the venting tube extension elbow isn't pinched.

See details starting from post #96 here:
- E39 (1997 - 2003) > Good Replacement Batteries for the e39?

Originally Posted by pleiades
The positive terminal plastic cover on the original BMW batteries will fit into the Duralast battery because the "feet" have the same spacing

Here is a picture of the 'feet'. The spacing is very similar although the more substantial BMW positive terminal cover is better built all around.

I found it only slightly difficult to press fit the little feet into the holes in the Duralast 49-DL battery - but overall - it's a much nicer component than the flimsy Johnson Controls piece.

Originally Posted by pleiades
but the original BMW version has a gap that I found useful to channel the Duralast vent hose across the terminal and through and into the car-side hose.

Hmmmm... I don't see what you're talking about - but - I do see that the BMW positive terminal cover is muuuch more undulate than the cheaper flatter Johnson Controls cover.

Would you kindly snake a drawn arrow where you're suggesting we route the flimsy battery vent tube (this will help me, and also everyone to follow in our footsteps - so it should be worth the effort):

Originally Posted by QSilver7
shortens the distance from the battery's vent hole to the side of the car...and allows the tube to amble over to the car's vent tube.

That idea should work!

Notice in the picture above and in the picture below, the elbow of the Johnson Controls battery vent tube extension is pinched by the plastic sides of the BMW E39 battery compartment.

I understand what you say and will see if I can shorten the battery side of that flexible elbow, in the hopes that it prevents it from being pinched (for others, please look here for what happens if the vent tube isn't venting).

Originally Posted by QSilver7
Here's a pic of the OE cap that covers the positive battery cover...installed on a Duralast 49 DL.

And, here's a QSilver7 picture of a similar (maybe even the same?) battery showing that the Duralast 49-DL vent elbow isn't pinched in all cases; at least this QSilver7 picture seems to show slightly more room for the elbow than I seem to have in my battery compartment.
- E39 (1997 - 2003) > Battery Weak found Replacement

Originally Posted by QSilver7
Nice find. Just go back and make sure...positively make sure...that they INSTALLED THE VENT tube to the battery. You do NOT want to be driving around with the battery NOT vented. If it's an EXCIDE mfg'd battery, then the battery's vent hole should be on the side of the battery like the original BMW battery that was installed. So you won't be able to see it because it's on the side of the battery by the positive battery post. If it is a Johnson Control mfg'd battery...then the battery vents from the top center (like the Duralast pictured below).

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Last edited by bluebee; 09-21-2011 at 01:57 PM.
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