Power antenna replacement?

[Keyzter2110]

Years ago the antenna on my E28 was snapped off, and now its finally time to find a replacement. I can hear that the motor is still working, so I'd like to just replace the mast assembly if possible but I'm seeing there are some differences in options. Its my understanding that I'll need to find a matching serrated cord as a smooth one won't work for whatever reason. I'd like to avoid spending $100 on the Hirschmann Universal assembly since my motor is still operational.

Here is one option:
https://www.ecstuning.com/b-mtc-parts/a ... 68225~mtc/
Since it is priced pretty cheaply I'm questioning its integrity. Does anyone have experience with this particular version?

Thanks

[stuartinmn]

I see Hirschmann brand replacement masts on eBay for around $50 - not cheap, but certainly less than $100.

[Federico]

For $13.90 I would give it a try. It's not like you are replacing a rear main seal and you need to get it right the first time.
If this antenna fails, so what?

[Mike W.]

Looks like Autohausaz has them for about the same or slightly less, but in stock.

https://www.autohausaz.com/catalog/k/bm ... 5i/antenna

[HayekFan]

I just bought the Uro replacement mast shown in the AutohausAZ link, except I bought it on eBay because there was a local seller. I'm hoping to do the replacement this weekend. My motor works and the antenna goes up most of the way, but the bottom two sections are seized together causing a bunch of noisy clicking sounds when it gets near full extension. I've tried PB Blaster and tried "helping" it extend but no luck.

I'm wondering if replacing the mast can be done externally without opening the drive mechanism box or if you've got to open it up.

I will mention that I was able to loosen the upper nut on the antenna mount by carefully sticking a pair of small needle nose pliers into the two notches. I then turned the needle nose pliers with a pair of small channel locks. I have a feeling mine may have been an easy case, though, because there was almost no corrosion to have to break loose.

[Mike W.]

Long ago now I replaced mine by just motoring it out and feeding the new one back in. YMMV.

[HayekFan]

Uro antenna mast arrived today...



Nicely made for an aftermarket part, I think. Feels substantial, operates smoothly, nice instructions with diagrams. I'm thinking this was a good buy.

[HayekFan]

Long ago now I replaced mine by just motoring it out and feeding the new one back in. YMMV.

Yep, that's basically how the Uro instructions describe it.



Of course to do it this way you need a working motor/drive unit and a way to switch it on and off. I've got a working motor but will need to rig up a 12V control voltage.

[demetk]

When your ready to draw the new mast in just turn off the radio.

[HayekFan]

When your ready to draw the new mast in just turn off the radio.

Unfortunately I don't have a radio in this car at the moment.

[demetk]

Then go to your antenna and jump the red and white wires together. That will push the old mast up and out. When you're ready to draw the new antenna in disconnect the white wire.

[HayekFan]

Yeah, I know how to get 12V to the right spot to control up/down. I might do it as you describe or I might use the antenna enable pushbutton that I've added to my dash. If I do the latter I'll need to grab 12V from somewhere, probably the radio constant supply, since it won't be coming from the radio itself.

[HayekFan]

Got the new mast installed. Works perfectly.

It's just as described earlier. Loosen the mast nut, then motor out the old antenna by commanding it to raise. Feed in the new antenna cable until it engages with the drive mechanism teeth. Command the antenna to lower which will cause the cable to be pulled in. Thread in the mast nut and tighten it. Raise and lower the antenna a few times so it can find its home position and you've got it.

BTW, earlier in the thread I mentioned loosening the upper grommet nut that has the two indentions. That nut does not need to be loosened for this procedure. Only the mast nut needs to be loosened which is easily done with an adjustable wrench. I know this is obvious to most of the folks around here but I'm noting it for people googling this thread in 2035.

[glowell222]

Been using mine now for more than a year. No probs. About once a month I clean the antenna mast with a shop towel and a spray of wd40.

[tbrints]

Just a note for others, my mast nut was was pretty dang tight/stuck..!
I had to remove the entire Hirschmann antenna unit on my M5, then removed the cast piece that the antenna cable from the radio screws to.
Put some PB Blaster down in, finally came loose. Little grimy on the tiny threads after 31yrs.