"ticking" noise from the top end of the engine

[panda234]

I just noticed a ticking noise from the top end of the engine. I had it out for a 200 mile or so highway drive  it's a hot day) and didn't notice the noise until I slowed right down. It's fairly pronounced and from the interval seems to be from one cylinder. It's a tick as opposed to a tack, so maybe a valve? My mechanic can't see for another 10 days so I"m kind of stuck until then I think... :-(

Bill

1970 280SL
49,000 miles

[graphic66]

First I would check your plug wires. They can arc and cause ticking. Start it up at night and look for visible arcs. A long shot, but I have seen the problem before.

[Benz Dr.]

It could be an ignition noise - not sure if you would hear it all that much with the engine running. More likely to be a valve rocker or something like that. When is the last time you set your valve lash?

[panda234]

I got it into the mechanic and he says it's valves. He won't be able to look at it until next week but I could have damaged the camshaft because when I was on the highway I couldn't hear it with the top down so it might have been making the noise for a while. I could be in the market for a camshaft... :-(

Bill

[Benz Dr.]

That's doubtful. If it was only making that noise for a while it wouldn't wear the cam that fast. Sometime the ball studs will start to turn from going loose. If that's case you will need to replace any that turn easily. They should only turn using a fair amount of force.