1984 300sd PLEASE HELP white smoke
 

Hi after countless hours I can't fix the smoke issue.
I had it start smoking bad and smelled of unburnt diesel, then I discovered 2 of my injector prechambers where destroyed...
Replaced and still smoking.

Ip timing is fine I have even advanced and retarded it and no change.
I have also swapped injectors as I thought maybe my new bosio injectors, with a set from a donor car.

Its not burning oil that I can tell and I can't notice any coolant loss.
Car does not over heat or have any other symptoms other then a slight irregular miss fire at idle.
Please anything will help

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You say you found that two prechambers were destroyed.

Where did the pieces of the prechambers go? Did they fall into the combustion chamber?

I have no idea... I put a magnet all the way into both cylinders to see if I could find anything and absolutely nothing, so then I put a grabber claw into it and moved it in every direction and heard no noises or uneven areas in the cylinders... I have looked in every thread to find out why its smoking and I stumbled upon the prechambers being damaged on accident... Can you tell me if the hole on the ip which the a-b timing light or lock dowel goes into is supposed to have lots of black oil come out of it when I removed the 17mm bolt?

I can't answer on the IP question. Sometimes it's best to make a supplemental question like that another, new thread.

In the below I am assuming you are using Diesel Fuel.

It was a Long time ago but someone posted some pics of Prechambers that Bad Injector Nozzles spraying on the Chambers had caused. If Fuel Is sprayed onto the walls of the prechamber it eventually cuts through them and does the same to Glow Plugs.

Low Injector opening pressures do not help either.

White Smoke can be unburned Atomized Fuel.
When I had that happen is was indeed extremely late Fuel Injection Pump timing. I got billows of white slightly Fuel smelling smoke. In my case doing a proper job timing the Fuel Injection Pump fixed that.

However, one also has to think about the Unburned issue. If there was Cylinder or Cylinders with poor compression that create enough heat to burn the Fuel you would also get white smoke.
A Compression Test might answer that one.

The other cause of white smoke; coolant leaking into the Cylinder from crackes or Head Gasket. A Head Gasket issue could also cause a compression loss issue and it does not have to leak to the out side. You can have a Head Gasket issue right between 2 ajacent Cylinders. That would show up on a compression test as 2 low cylinders in a row.

Or a some combinatin of all of the above.

You said you are not losing Oil but I am going to throw in that if the Seal on the Turbine End of the Turbo is leaking a bit the Oil will burn and ceate some smoke. But, it would not smell like Diesel Fuel.

I am not sure what would happen if there was some problem with the Timer as I have never read any threads where one broke. But, if that Timer was not advancing as rpms pick up that would make your Fuel Injection Pump timing late.
If the above was the case I think it would not smoke much at idle speed but would smoke a lot as you accelerate.

Sticking Compression Rings would lower compression.

I didn't read that you pop-tested the injectors. The main thing that would cause unburnt fuel is a bad spray pattern like a streamer or a leak when closed. I doubt that mis-matched pop pressures would explain your symptoms since I recently found 3 of 5 injectors in my 1984 were non-turbo (1600 psig), but the engine had run fine like that for years.

If the injectors spray OK, my next suspicion would be the IP. Perhaps someone put the delivery valve parts in #1 back wrong after a "start of delivery" check. With the engine idling, loosen the tube nut and each injector and see if each cylinder contributes the same. It should idle pretty rough with each cylinder disabled.

Finally, while the injectors are out, inspect each pre-chamber with a video camera. I have a small USB "endoscope" one I got for $18 on ebay. It has an integral LED light. I haven't tried it on pre-chambers yet, but it shows my tonsils well. Should also work to search for hemorroids (yuck).

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There is always a pool of Oil inside of the Fuel Injection Pump because the area that the Oil Drains out of is higher than the top of the Fuel Injection Pump Camshaft Bearing up front.

For those people who want to drain every speck of the dirty Oil out of the Engine the old Oil in the Fuel Injction Pump is one of the Reasons why that is not possible.

On a 1985 you should have a small about 1/4" diameter Plastic Oil Supply from the front of the Engine to just above and to the front of the Fuel Supply/Lift Pump.

I just though of something else that will cause white smoke. It is possible to have an small insidious Air leak. Tiny Air Bubbles inside of the Fuel Injection Hard lines will keep the Fuel From Being Injected properly.
If you have the Old Style Hand Primer with the Shiny Aluminum Body that is a know major source of Air Leaks. It should be replaced by the New Style Bosch only one.
You can cheaply replace the to Fuel Inlet Hoses and that Plastic Filter (sometimes has tiny crackes in it). Regular Fuel Hose from a reagular Auto Parts Store is rated for Diesel Fuel. 5/16" inside diameter works fine.

Hi first and formost I want to say thank you BillGrissom and diesel911 as I appreciate the both of you for responding with solution based responses. The lack of this is what had kept me from joining this site till recently . Onto my answers, I was cuyrious about the amount of oil in the ip as I had read on that a tablespoin of oil is within the ip, and upon checking ip timing I have had as much as 6-8 oz of oil come Out... I DO have the old style primer pump. I just ordered a entire new one with the mount. And went to a local shop in Denver that works on German cars only which I heard had excellent customer service and the owner loaned me his compression tester I will report back with readings. I see no point in buying the compression tester when I can buy a new headgasket and timing chain for cheaper.

My compression results cylinder # 1- 5 = 0. I'm confused as the car still runs and drives with NO other problems other then the white smoke that smells of diesel. It even smokes when I run it on straight diesel purge.I just went thru and checked all valve clearances and no issues there. I must be missing something very simple. Any suggestions greatly appreciated.

Thx Kaz

How much white smoke? Like a smoke machine? All the time or only when cold. I have had a 1981 300SD smoked like a smoke machine, stream of white smoke went for 50+ yards. It was so bad that no car would come anywhere within 100 yards. It was the turbo and it was replaced, no more smoke.

White smoke, lot of it, IMO is always turbo. Good luck.

Yes like a extremely thick when I push on the accelerator, not soo thick when idleing. I have less then 1mm of play side to side no play up/down, and no play in/out. Maybe I should disconnect the turbo and see off it does anything? But 0 compression in all 5 cylinders?

It could not run on 0 psig compression in all cylinders, based on thermodynamics (must have area under the P-V curve). You must have used the compression tester wrong. My Harbor Freight tester cost ~$20 on sale, as I recall. Assuming you measured thru the injector hole, did you try putting your thumb over the hole as a friend cranked the engine? You should feel air blow past your thumb once per 2 crank revolutions.

The turbo-charger is a likely candidate. Sorry I didn't think of that. When the oil seals fail, it drips or sprays engine oil into the intake or exhaust, which will smoke bad. I recall some fraternity floats at Ga Tech that dripped auto trans fluid (light oil) into a carburetor to produce plumes of white smoke. The seals could leak without causing play in the turbo-charger (worn bearings).

Hi Bill thanks for the info, can you tell me if there is any way I can check for the issue bein the turbo seals other then play in the shaft?

At the rear of the intake manifold, there is a plastic tube. T in a boost or pressure gauge there and run it into the cabin. You can check boost pressure while you drive. You should get a good 9-10PSI under full boost.

To check the turbo bearings, you can try moving the compressor wheel on the XYZ axis to check for play. Minimal play is OK but if you can move it in and out or it touches the housing, that is not good.