What is this noise? Suspension, or perhaps engine or steering mounts?

[relbhcb]

I have had my 1964 230SL for a couple of months now, but I have noticed a "clonking" noise coming from somewhere under the bonnet. I notice it most when using the car from cold & when driving up my drive (steep uphill slope, followed by a drain grate just after the summit), but it can more often than not be heard whenever I go over a bump.

I have recorded a short mp3 sound clip on my phone in the cabin, and you can clearly hear me going up the drive, changing gear at the top, and then the clonking noise at "time 16 secs"; I then stop and reverse back over the grate and you can just hear the noise again at "time 28 secs".

http://www.bartholomew.co.uk/230sl.mp3

I am 99% sure that it is not the drain grate itself, but driving over it causes the noise.

Any ideas?

[w113dude]

Have you checked your subframe mounts? or possibly your engine mounts?

[George Des]

This could also be your kingpins. Had this problem on a 71 280S. The tops of the kingpins were so worn out that the top section was floating and every time I came to a stop or hit a bump the top of the kingpin would ride forward and make a heavy clunk.