bigcoupe.com

Real quick question - is this repairable or do I need to buy a replacement mast & spline?

Edit: Scroll down for a detailed teardown guide.

That mast is toast.

Yes it's repairable. Do a search in the Tech section (antenna repair) several helpful posts. Roger

The antenna as a whole is repairable, but the broken mast isn’t.
So, yes it’s repairable and yes you need to buy a new replacement mast.

Thanks all, most of the links and photos in the previous threads are dead unfortunately, but I did get enough info to work through it myself.

Any recommendations for an online shop who sells a cost effective replacement antenna please?

I'm also on the lookout for 2 other parts - I have a screw-mounted antenna.

• The seal/grommet/gasket piece that attaches to the teeth of the metal bracket and sits under the body metal.

• The little black rubber ring that goes under the chromed "BMW" spacer.

EDIT - PROBLEM SOLVED!
See below or click here:
viewtopic.php?f=11&t=32796&p=233521#p233521

For the record, here are some more photos of the Antenna teardown and cleanup that was in my Australian-delivered BMW 1986 E24 635CSI.
Hope this helps someone else in the future.

Other sources of reference:
viewtopic.php?f=6&t=17530
viewtopic.php?f=2&t=27467
viewtopic.php?f=2&t=14298
viewtopic.php?f=2&t=11445
https://www.youtube.com/watch?v=LiE1PTJHEJM
https://www.benzworld.org/threads/hirsc ... e.1432845/
https://www.500eboard.co/forums/threads ... enna.7102/

Parts:
https://www.autohausaz.com/catalog/k/bm ... s=r&page=1
https://www.eeuroparts.com/Cars/BMW/143 ... ch=antenna
https://www.ecstuning.com/Search/SiteSe ... 4_antenna/

The nasty foam gasket and the rubber grommets are NLA.
See below or click here for a work-around.
viewtopic.php?f=11&t=32796&p=233521#p233521

Teardown and cleanup

Hirschmann Auta 6000EL antenna unit.
The "362" variant mark denotes the upper mast mounting point hardware & vehicle electrical connections.
Internals are the same between all variants.



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Out of the car. Lots of water scaling on the case.



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Source of the water problem. Under-body mount sealing gasket is totally stuffed.



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Exploded parts diagram for reference.


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Open the case by gently unclipping all the snap-clips around the unit. Thankfully there are no hidden snaps, so just take your time.
(No pics unfortunately)

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Unscrew the chrome tip to free the telescopic antenna.
Unscrew the brass Y bit from the aluminium pipe.





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My antenna was a Hirschmann H 04, which means "4 telescopic segments".



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Remove the inner aluminium pipe from the fixed outer sheath. No screws, just gently push it of the pipe.
You might have to fish out the rummer grommet from the winding unit afterwards.
Also note that one end of the tube is round, the other is hexagonal. Round goes into the winding unit. Hex goes outwards.




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Original connection layout of the control circuit board.



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Disconnect the motor wires to allow the winding unit to be removed.



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Bench testing the motor. Works fine.
Apply +12VDC to the motor to wind out the damaged spline.




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Unscrew the guide rail to clean inside.
After cleaning, this is the only metal-on-metal part that I applied new lithium grease/lubricant to.
Nylon parts do not need additional lubrication. Adding lube inside will just encourage dust to gunk up the mechanisms.



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Remove the circlip to easily pull everything apart.



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Unscrew the motor bracket to get access to the worm drive.




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Clean up all the parts (except the electric motor) with degreaser & WD40.
Use a toothbrush and toothpick to get into the crevices.
Reassemble in reverse order.



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Don't forget the rubber standoffs. 6 in total: 3 below, 3 above + 1 bumper in the lid




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Align the rubber standoffs with the lid pins and carefully snap the lid closed.



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Reattach the brass Y piece.
Use the adjustment screw to make sure it points in the original direction.


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I need new grommets and a new antenna to complete this installation.

PART 2 BELOW
The nasty foam gasket and the rubber grommets are NLA.
See Part 2 below for a work-around:
viewtopic.php?f=5&t=32796#p233521

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That's an EXCELLENT write-up with great pictures!

THANK YOU FROM ALL OF US.

I rebuilt the one in my '85 325e and swore never again. Multiple tries over a week's time. If I'd had this to guide me it would have been a much less harrowing experience.

Brilliant write-up and pics.

Many thanks.Will be referenced frequently.

Have moved it to “Tech.Articles”.

Wow! Great write up - and the pictures!!!

I replaced my mast about a year ago and was concerned that I would need to tear into the motor. I got lucky and the mast went in without a problem, but I was concerned about having reference material if I needed to delve in further. No longer a problem.

Thanks

Scott Beaudry

I love this thread!
So awesome.
Thank-you

Update time.

Short version: I found a cheap work-around for some unobtanium parts.

Long version:

I've been searching far and wide for 3 parts to complete this repair:

1. Antenna mast (Found pretty easily - Search "Hirschmann Antenna Mast". Mine is a 4-segment mast with a toothed nylon spline)
2. Foam gasket that sits under the body, on top of the toothed adapter ring.
3. Rubber washer that sits under the chrome ring.

Impossible parts

The foam gasket is impossible to find.
Nothing from BMW. Nothing from Hirshmann (I called). Nothing on eBay or any of the usual parts suppliers.
Judging by the looks of the foam after time, I'm not sure I even WANT to replace it.
Here's what a fresh foam gasket looks like, followed by my nasty one out of the car.





Here's what the rubber washer looks like:
The rubber washer can be found second hand, but the price is daylight robbery.
Example: There's a complete chrome ring tip including the rubber washer on eBay for US$125 at the moment.
https://www.ebay.com/itm/185215169162






Workaround

So I went searching for an alternative and found the PERFECT fix for both, in a single product!

1" rubber blanking grommets from my hardware store.

Packet


Top


Bottom


Profile


Radius test



Testing

Slice out the centre with a craft knife.
Don't slice too much - You want a tight fit to help with water sealant.


Install in this order






To the car

The hole is 22mm diameter.


I thought the grommet wasn't going to fit at first, but it fits perfectly in the groove on the profile.
You can see where the boot was resprayed after a previous rear-end accident. They didn't bother to take the antenna out and just sprayed around it.


Test fit
This picture makes it look like I cut too much rubber away, but it's actually a nice and tight fit all around.
But to be sure, I added some plumbing thread tape to reduce the chances of a leak.




Installed.
Slightly smaller than the original washer, but it works well.


Underside. Nice and snug.
These pics were a test fit without the rest of the antenna body attached.


Fully installed again.
I dismantled the chrome and brass bits, and installed them back onto the antenna neck for this final installation.


Next steps:

Waiting on the antenna mast that's on order from my local friendly Bavarian Classics workshop.
This can be reinstalled from the outside without dismantling the motor body again.

Very nice workaround, and again, great pics!

Scott Beaudry

Can anyone confirm the movement of an uninstalled antenna mast please?

I received a new (old) antenna mast and spline recently and was bench-testing it before installation.

I can't manually extend the telescope. I've tried pulling it out by the tip and pushing it out by the spline, but it feels locked in-place.
It appears to be in good condition, no obvious kinks or bends.

My old broken one was able to extend freely, even with a small kink in the shaft.

Should it be able to manually extend and retract freely like this?

No. If it's an intact, working automatic antenna, it cannot be manually extended or collapsed. Doing so will break the actuator. Ask me how I know.

TimU wrote: ↑Wed Feb 09, 2022 1:26 am Can anyone confirm the movement of an uninstalled antenna mast please?
[...]
Should it be able to manually extend and retract freely?

Update:
Yes, it should extend freely (before installation into the motor housing).
There is no hidden locking mechanism or anything mechanical to stop it extending.

My replacement mast's telescoping shafts had seized with old grease or whatever.
I had to put a fair bit of effort (and solvent) into freeing up the telescoping shafts, but it's running nice and freely now.

After freeing it up by force, and then thoroughly cleaning the shafts, I gave it a little spray of lithium grease to help keep it running smoothly.

My antenna, mast and motor is now complete and functional

Sorry, I missed the "uninstalled" part. As Tim said, it should extend and collapse easily by hand before it's assembled to the drive.