1984 300D Noisy Turbo

I have a strange noise that sounds like a fan with bad bearings. I hear it when the car is under load (going up hill) or just hard acceleration. Sounds to me like it is coming from the turbo. Is there any typical recomended areas to inspect that would cause this such as the EGR valve or intake manifold for this car. Also is there a cleaning solution that can be directly sprayed into the Turbo?

Forums

Diesel Engine Specific Aid

Chassis Model Number

W123

Why does it knock?

There are three or four places you should check. See my manual on Why Does My Diesel Rattle and Knock. Also check Tech Help page.

Noisy turbo? Are you sure?

Hi Smarra. I know I am responding a little late. If you went ahead and followed up on Kent's advice, then I'm sure you have plenty of areas to check and you may have found the culprit by now. All I wanted to say was, don't be too quick to point the finger at the turbo. The turbos are pretty robust and not typically prone to failure as they are lubed and cooled with plenty of engine oil. I own the same year 300D and have done my share of wrenching and fixing this and that.

Thanks for the reply usmc.

Thanks for the reply usmc. I am not 100% sure, but I can't think of anything else that would make that type of noise and would be directly linked to acceleration. The noise has been getting better slowly over time. I have had this car about three years driving it on and off, prior to that it was sitting much more than it was driven as the car had under 100,000 miles and the turbo was not operating because the wastegate hose was broken. Also, I did all of the tuning and even installed new injectors, the car runs great but was a little too slow for me, and therefore I adjusted the wastegate a little (3 turns). The car is much more driveable now. The noise was the same before and after adjustment except that after it was a little bit louder. The air inlet elbow is tight, therefor no obvious air leak. Let me know your thoughts.

Getting a reply is always good

Yeah Smarra, getting a reply is always good as 2 or more heads are better than one and that is what this site is all about. I have a couple of questions posted and I thought for sure someone out there had to deal with something similar but so far nothing back. Any way let's talk about your ride. You sound like you have done a little wrenching yourself adjusting the Westgate and all. I would have to write for a long time to put down all I have learned about these great cars and I learned most of it from Mercedessource. For short money you can purchase one of the manuals that would give you some direction in solving your problem with the "mystery noise". You mentioned the sound got a little louder after the Westgate tweek. I don't know maybe the sound is originating there, but you know how these cars have a little more "shake and rattle" than a gas job especially if everything is not just so. Sometimes where the sound is coming from can be deceiving that's why the manuals available help to cover a lot of ground. As far as your remark about the car being a little slow, have you cleaned out the bolt and banjo fitting that carry boost to the injector pump? It is located on the back of the engine near the fire wall. Look at the valve cover near the fire wall and you will see a clear line below going to the intake manifold there. The line may not be clear any more and that could be part of the problem with lack of zip and acceleration. Undo the bolt. It is long and hollow but may be plugged with soot and oil. Clean it out, and the line if necessary, and then put things back together. It only takes 15 minutes tops and if you find it plugged up and you clean it out, this is the easiest "effort for gain" you will ever encounter on the car. I got the Diesel Performance Tuning and Repair booklet and it is covered step by step and let me tell you mine was plugged solid. After cleaning and reassembling, it was like a different machine. My 1984 300D went from dog to rocket. When I put my foot into it now the "ponies are cut loose" and she goes. Give it a try if you have'nt already and you will be a believer.
Later

"dog to rocket"

I have made several posting also in the past and had no reply, sometimes the question is difficult to answer as there are too many variables based on a short post. If you do not get a reply, do some troubleshooting on your own and rewrite the post based on what you find, that has worked for me. As for my ride, I own about 80% of Kent's manuals. Yes, I replaced the ALDA line and cleaned the banjo bolt, it was mildly dirty, I would bet that my turbo had not been actually working for over a decade. When I said the car was slow for me, it ran like a diesel with the the amount of slugishness from a stand still that a 1984 is know for. After adjusting the wastegate, it now runs like a gas car. As for the noise, I think that things inside the turbo are slowly returning to normal as I continue to drive the car, it now sounds similar to squeeky fan belts.

Sal