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'85 300TD Turbo
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18 Posts
Discussion Starter #1
Hello all. I just bought my 85 300 TDT a little while ago and am getting a weird noise. When I am driving at slower speeds (35-40 mph) and when I am coasting after driving faster (like a freeway off-ramp) I am getting a whining/howling noise of varying pitch and volume from under the hood. My hypothesis is that the bearings in my turbo are starting to go and when it is spooling down under light engine load it makes noise. It sounds fine when the engine is under load. It is definitely engine related, but not tied to RPM.

The wagon has 193K miles and, from what I can tell, the original turbo. There's no discernible play in the rotor shaft when I took off the intake elbow to check it out. It is a KKK unit, if that matters. Has anyone heard of something like this?

Cheers!
Alex
 

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1980 280CE; 1982 300CD
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1,440 Posts
I haven’t heard much about actual whining from these turbos, but it sure seems plausible at 193k. I just rebuilt the Garrett on my 1982 300CD, and it was fairly cheap and easy to do. THere’s lots of tutorials out there, including some YouTube videos for similar turbos.

FB
 

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'85 300TD Turbo
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18 Posts
Discussion Starter #3
I have a Garrett on a very low mile spare engine. I will eventually drop the engine in, but for now I think I will swap the turbos and see if the noise goes away. One more thing to add to my list of projects 😬
 

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W123 300CD, W123 300TD, W202 C250D Turbo
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400 Posts
I have a Garrett on a very low mile spare engine. I will eventually drop the engine in
As an aside, is the spare engine from a wagon ? As the casting on the head for the SLS pump is unique to wagons (and some sedan (that outside North America got SLS). Some early 280CEs got SLS as well.

I am just in the process of "upgrading" a spare OM617A I had to the SLS version. Got an old normally aspirated wagon head (they have the same casting) and had the head ported used the larger (and sodium filled) valves from the original tubo head.
 

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'85 300TD Turbo
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18 Posts
Discussion Starter #5
No, it's not a wagon engine. The PO removed the SLS and converted the car to conventional suspension so I don't think I will have an issue with the non-wagon engine. Sound accurate?
 

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1982 300D Turbodiesel (US Spec)
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238 Posts
Have you tried to replicate the noise with car parked? I would use a stethoscope to listen to the turbo to verify if something sounds wrong. I would also check all accessory pulleys to make sure the noise isn’t coming from somewhere else.
 
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