Mercedes 450SEL 6.9 engine ticking/noise

[harrycarry250]

I have not thought to check the rotocaps specifically. But I have spent many hours staring at the valvetrain and I did not notice any abnormalities. Exhaust manifold is solid, if that is what you're referring to.

Thank you

[tcj]

broken rotocaps do make such noise.
A (small) crack in the exhaust manifold can add to this too. Look for gas pulsing on the downside of the exhaust manifold.

[Gpapaniko]

I had an intermittent loud ticking noise on my M110 engine and found it was the air filter housing hitting the valve cover occasionally, especially when the engine was warm with just a little bit of a rough idle - the point is, I starting thinking it was a rod bearing and ended up with something super simple.

[harrycarry250]

Thank you, yes that is the most logical thought process and id like to believe I have considered all the small potentials.

This has been an issue for over 6 years.

I've had cars with bad rod bearings and this doesn't really sound like one, but you never know.

To those who have had the pump noise. Did your suspension function as normal?

[daantjie]

I still highly doubt that the suspension pump could make such a racket. You could take a mechanics stethoscope and put the probe to the pump to see if you hear this clacking noise inside the pump.  Sometimes these very basic tools can be quite helpful.