HELP!! My 83 240D is making a sound! - PeachParts Mercedes-Benz Forum

frogboy · #1 05-15-2003, 01:56 AM

Hey everybody, I really need some help on this one because I am clueless. My 240 is making a clinking sound when it is running, even when it is idle. It sound like a high pitched metal clinking sound that happens 2 times a second. I am baffled, but if you guys have some suggestions I would love to hear them

#2 05-15-2003, 07:24 AM

Are the air cleaner mounts okay?

Good luck,

#3 05-15-2003, 12:18 PM

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leathermang · #4 05-15-2003, 01:25 PM

I will bet I know... LOL.. check the thin metal plate on top of the motor mount... mine clinks also.... it is probably called a heat shield for the rubber ....

frogboy · #5 05-15-2003, 10:08 PM

okay, so I did a little more investigating, and I have a list of symptoms.

1. When I first start the car, i don't really get the clinking sound. Also when I am driving the car, as in accellerating, i don't get the clinking sound either.

2. when i step on the clutch, I do get the clinking sound if I am traveling less 30mph.

If it is the motor mounts, that sounds like it could be it, only because of the fact that the engines seems to vibrate and shake around a lot more when the car is in idle, because it seems more stationary when it is working harder, like when you are in idle, and you have the idle switch turned all the way down, the engine shakes a lot, but when you have the idle switch all the way up, then it does not appear to shake.

If anybody has any suggestions, or can agree that it would be the motor mounts

leathermang · #6 05-15-2003, 10:39 PM

Put your hand on the little thin piece of metal on the top of the driver's side motor mount... you can tell if it is loose. If it is,,, then it is just a matter of what vibration rate excites it...

leathermang · #7 05-15-2003, 11:47 PM

...

#8 05-16-2003, 12:10 AM

A test for really failed motor mounts is to push the engine sideways by pushing on the valve cover. If it moves more than an inch side to side the mounts could be weak. Diesel mounts do not last more than a couple years and are readily attacked by the solvents in most engine cleaning products. If the mounts are original also consider replacing the tranny mount at the same time. Just make sure you complete the engine mounts before moving onto the tranny mounts.

By the way, why does the heat shield crack? Two of my cars have had cracks in the shields. Something has to cause a stress riser in the shield to get the crack started. These cracks start near the bolt hole and work outwards. Could the shields be getting re-installed on the wrong side of the engine? It appeared they only go on one way.

frogboy · #9 05-16-2003, 04:05 AM

thanks for the input, but it was my girlfriend's car, and her father is really into these cars, he is the one who got me into these cars, and he came over and found that it was the alternator bearing that had gone bad, and it began hitting the fan. I trust he is right on this because he knows a whole hell of a lot more about these cars than I do now. He is the one with the intercooled turbo thread with all the pictures.