Help

Hi all may I start by saying thank you for such a wonderful forum and fantastic info. I have been reading these forums a lot and have learned more that I thought was possible.

My Car: 1984 Mercedes 300sd Turbo Diesel - 126 body California model (I think)

History: I bought this beauty a month ago for $2000 and spent about $2000 and 2 weeks solid on the following.

* New tires and rims
* After trying to get an alignment needed new steering rod arms, done + Alignment
* New front brake assembly - The front brakes were shot and on inspection it was apparent there was 1 x 126 front brake assembly on the left, and 1 x 124 front brake assembly on the right, so I had to have that sorted out and got it all back to uniform and new pads.
* Changed transmission filter, fluid and gasket
* Changed power steering filter and fluid
* Changed Oil filter and oil
* Changed primary and secondary fuel filters
* Changed all V-Belts
* Oil pan gasket
* Diesel purge with Lubo Moly

After all this she was driving great. Starts first time, without any acceleration, No smoke, perfect idle and very little noise. Great power even on hills, and was an absolute treat to drive.

I added 5 gls of Veggie oil (New and clean from Costco) and 10 gls of Diesel and it ran and sounded even better for a week. So quiet and so clean it was just amazing to drive and I got excellent mileage. I took her on a road trip to LA and it was great until on the way home I stopped off for some fuel in a out of the way service station and within minutes I noticed a cloud of smoke following me? I figured it was perhaps mist or condensation as it was a bit of a cold night and continued to drive the hour home back to San Diego. The next day in the light of day I noticed that there was a LOT of black smoke coming out of the exhaust and a loss of power, especially on load (ie: going up hills) and even more smoke.

I suspected it was contaminated diesel and after talking to a friend he said it sounded like I got a bad batch of Diesel and could dilute it out so I removed the return fuel line into a jerry can and drained most of the fuel out and filled up the tank to 1/2 and then attempted to drive the bad fuel out. I have been driving the freeways around my home for 2 days now and the smoke seems to come and go from Terrible to just bad. I got to almost empty again and again filled it up to 1/2 with good fuel as to dilute it but it is now two half tanks on good fuel and it hasn’t really helped at all.

Now: Starts really badly and I need to rev it just to start it up. Lots of black smoke that seems worse of a night time but it might just be an illusion and definitely worse under load or hard acceleration. Loss of power, like down to 40 mph on hills that I use to roar up doing 70. A loud knocking noise at idle and low speeds. Increase in Temp with the temp gauge going well above the 80 mark where it use to never move above this.

On the freeway, on the flat, doing 70 she seems to run quiet and minimal smoke and almost for a moment or two seems to be ok.

I am at my wits end and almost ready to give up. I really don’t know what to do. Most of the work above I did myself, learning from these and other forums so I’m fairly mechanical and handy but have no real experience with diesel engines or Fuel Injectors.

Is it possible that it was not contaminated diesel but just a total coincidence that something occurred around the time I filled up? Or have I done damage to the engine / Injectors by driving it in this condition? Or .....or.....or.....is it something all together different.

Please Please Help as I really need some help and advice on this. I have read that it is not that hard a job (timely yes) replacing the injector nozzles but I don’t want to go through all that if it isn’t the issue

Sorry for such a long blurb but I just wanted to be as detailed as possible.

Again Thank you all so much and any information, advice or experience as it is greatly appreciated.

Cheers James

 

Hi the new nozzles arrived today and it was a easy pleasant job replacing them. The old nozzles were in bad shape and very clogged up with black soot/mess. Following Diesels Giants walk through I thoroughly cleaned the injectors and installed the new Nozzles.

One thing i noticed when i removed the injectors was that they had what appeared to be black engine oil on the bottom of them where they screw into the engine block. From this I can only deduce that either the piston rings have blown or the head gasket/head is blow/gone letting oil get into where it is not meant to be. Would this be consistent with the knocking, loss of power, and thick black smoke from the exhaust? Do you think i have gasket/head/ring issues or is this normal (I cant imagine)

Thank you for all your help info.