Do you hear what I hear....??

Let me throw this out to you.... on acceleration from a stop to about 15-20mph, I hear a muffled tapping sound from the right side engine compartment. Kind of sounds like the sound of a baseball card flapping on bicycle spokes. It doesn't do it all the time , but does it enough to concern me. It does not do it if I rev the engine, only on motion acceleration. This is happening on a 1989 560SL.
Appreciate all replies.

George

[Walrus]

I was hiking one day, several years ago. Upon approaching a rocky clearing, I began hopping from rock to rock when a bronze-colored flash caught my eye. As I neared closer to where the "thing" appeared, I heard a distinct "rattling/buzzing sound"... Instinctively, I high-tailed it in the other direction. I had never heard a rattlesnake before, but I did not need anyone to tell me that was what it was! A little while later, after I had recovered my composure, I ventured again closer to the last sighting... Sure enough, It was a rattler.

In other words... I have never heard a chain-slap on a 117 engine, but I think I would recognize it immediately... And I would expect it to sound like you described.

I think I would get a second opinion rather soon... maybe even tow in to shop rather than drive.

Tow cost... $70 bucks
Engine replacement... $7000 bucks
Piece of mind... Priceless

[DanielG]

Yes -- I use to hear it -- check out this thread:

Fluttering noise on acceleration


It turned out the rear axles needed to be replaced. I heard the sound from the right rear (not the front), so maybe its your front axles?

Walrus and Daniel G., Thanks for your reply. Walrus, I was told that for the timing chain to be suspected, there would be a sound emitted on starting the engine, even before shifting into gear and then into motion. But I agree, my first concern was a timing chain issue.

Daniel...I read your tales of woe and offer my condolences for your pain. I have the car going into the shop next week and will offer all suggestions that you have shared with me.

Again, many thanks to you both.

George

[tecqboy]

I had that very bad timing chain sound. There was no doubt about the source. It occured quite suddenly after a cold start. But I got real lucky. The problem was only the hydraulic timing chain tensioner. Much less expensive to repair.

[DanielG]

Hey George -- did you find out what was causing the noise?

Hi Dan...sorry for the delay in replying, just got back last night from Fla, and while I was away I had the car worked on. The noise turned out to be the timing chain so had it and all the components replaced. Picked the car up tonight and it sounds sweet. Also had the idle control valve replaced, as well as the sub frame mounts and front shocks. Bottom line....I spent some money.
Anyway, hope all goes well for you as the top goes down and the smiles begin.

Regards,
George