Antenna makes load noise when retracting

[twochaps]

I have a 1985 380SL. When I retract the antenna by switch or turning the radio off there is a awful noise when the antenna reaches the full retraction. It sounds like the antenna keeps trying to retract. The only way to stop the noise is to cut the engine and remove the key.
Any way to test the system to see if it is the antenna or the antenna switch?

Thanks for any ideas

[whunter]

You need to remove and inspect the mast, the cord may be damaged = replace the mast.

If the mast is good:
Remove the antenna motor assembly, and open it, inspecting for internal damage.

[twochaps]

The mast go's up and down smoothly and looks OK (w/o disassembly). When the mast is fully closed the nylon gears continue to turn for 5-10 seconds. I can see a very worn portion on the inner nylon gear. Should I continue to disassemble the unit for a deeper inspection or look for a new unit?

[whunter]

Originally Posted by twochaps

The mast go's up and down smoothly and looks OK (w/o disassembly). When the mast is fully closed the nylon gears continue to turn for 5-10 seconds. I can see a very worn portion on the inner nylon gear. Should I continue to disassemble the unit for a deeper inspection or look for a new unit?

Look for a good used unit, and/or salvage a good gear from another damaged unit.