Electric aerial is stuck in the half raised position

[dorsetdave]

I have just bought a '93/4 CD hatch and the radio mast is stuck in the half up state. Anyone have any suggestions or is it just getting a replacement? If so, any recommended supplier? It has the original Blaupunkt CD system.
Thanks for looking.

[Robsey]

If your aerial is sticking part-way up / down, the most common reasons are: -
1 - a dirty mast,
2 - the mast tubing is slightly bent or out of round.
3 - dirty or congealed grease in the aerial motor gearbox.

There are plenty of after-market replacement powered aerials for approx £20 to £30.

Original GM powered aerials are approx £100 more than that.

I would try cleaning the mast first, and check to see if there are any kinks or bends in the mast.

Remember to clean in an upward direction, so that you are not pushing dirt down into the joints.

Use a very thin cleaning oil on a lint free cloth. Not a thicker oil such as 3in1 or engine oil.
Thick oil will cause dust and dirt to stick to it, which will simply gum up the aeriel in no time.

If you think you have a minor kink or the tubing is out of round, try gentle re-shaping with a pair of pliers.
Cover the jaws with pvc tape or masking tape to avoid damaging the mast surface.

Finally - if you decide to take the motor assembly out of the wing, it may be a good idea to clean all the muck from the internal drive gear etc.

[dorsetdave]

Thanks Robsey.
The seller of the car is changing the brake master cylinder and giving the car a new MOT so it will probably be the New Year before it turns up. Just one thought, does the original coaxial lead go all the way to the radio in one piece or is there a connector? If it's the former presumably there will be a lot of trim to remove.

[Robsey]

There is a connector very close to the aerial, so no need to remove a load of trim.

Just the boot / hatch left side interior trim.

[Mazza]

Robsey has pretty well described the process in good detail. Didn’t know about the correct oil,.. but back in the day I dismantled a few electric aerials and thoroughly washed out each component. Worth cleaning once a year to take out the collected rubbish.

As an extra step, if you do decide to open it up for a thorough clean, then take a good few photos as it will help to put it back together afterwards.

There’s two types of electrical aerials. The earlier model black box was slightly bigger and had teeth on the lower section of the mast (hidden in the black box). There later facelift car had the thinner aerial box and toothless mast. Also the aerial tip was slightly different.

On the note of replacement mast, I’ve found the original look & operates better then the aftermarket ones - but also a little difficult to find nowadays, Unless you have a box of spares.

[Robsey]

Here is a link to my WIP, where I retro-fitted an electric aerial to my car.

viewtopic.php?f=21&t=4069&start=175

Scroll down a good 2/3 rds down the page.

[James McGrath]

Yep, i second everything already said.
Most of the time when and aerial gets stuck it's because it's dirty. Sometimes it's because it's been bent or put out of shape. Very rarely is it because the motor itself is warn.

Just one thing to add, you can also just replace the mast instead of the whole unit. It's much cheaper too. Part number: 90350788

[dorsetdave]

Thanks to everyone for their suggestions. Sorry that I have not been back earlier but my account was suspended due to my changing my e-mail address. I have just bought this car but the seller is putting it through a new M.O.T. and it wont be ready for collection until the New Year. As soon as I get it I will attack the problem using your suggestions & comments.
May I take this opportunity of wishing you the compliments of the season and all the best for 2019.

[dorsetdave]

Thanks again for everyone's suggestions. I collected the car and by the time it got home it was working fine. I gave it a good soaking in WD40 and hope that I will get a little more use out of it.

[James McGrath]

Excellent

They do requite attention from time to time.
I wipe the aerial down every time I wash the car to keep the muck at bay, that tends to keep it working for me.