OM602 smoking, noise.. new to forum and Benz

[Bigjake34452]

Hello everyone, new member from Florida, been lurking for long time finally registered.

I’ll start by saying I have purchased a 92 300d with 197k from a friend of mine of who owns a shop down the road from mine. Knowledgeable guy he does not do bad work. He had smoke issue from this car and assumed head gasket so he replaced the gasket had head checked all was good. Still smoked so there it sat for 4-5 years until I bought it.

Fast forward I have replaced all filters including tank screen, fresh fuel added. Changed oil and filter with a syn blend 15w40.

Issues I’m having is there is a constant smoke haze that’s blueish white that smells of fuel and burns the eyes. No matter if it’s cold or hot, idling or at speed, it’s always there. As well as a hard knocking sound I assume is nailing until the car has ran a good 20 minutes, or if the rpm gets above 1400rpm or so it will also stop the noise. During this period where the car is making this noise and is cold the whole car vibrates a decent bit, but if I loosen each injector line it will miss pretty hard with the same change for each cylinder, none of them seem to have less of an effect than the other. Once it has warmed up this vibration goes away, BUT I’ve noticed a low rpm miss when warm, like 700-900 rpm range there is a spot that you can hold the rpm and it misses terribly. Above or below that rpm is smooth as can could be. Also no matter the temperature this car starts incredibly easy, seemingly one revolution of the starter and she’s on.

I haven’t done a whole lot in the way of testing anything yet, would love some ideas of what I should look for and test for. From lurking I see lots of folks talking about delivery valve seals and washers, I will be replacing those but my IP is bone dry up top , no fuel leak.


Sorry for such a long first post but I greatly appreciate this forum and everyone’s insight , thank you

[jdulle]

I'd either check (pop test and check for spray pattern and no leakage), or replace the injector nozzles and see if it gets better.

[dieselbenz1]

Run a can or 2 of diesel Purge through it.

[greazzer]

If your nozzles have over 100k on the clock then they are worn. If they “pee” pre or post pop (or both), then you will experience your symptoms. You can run 100 cans of diesel purge but it will not fix your symptoms

[Bigjake34452]

Thanks for the replies, I will first try the purge. Then move to nozzles, are the nozzles difficult to replace diy?

[Rooster300SD]

The person to talk to about rebuilding your nozzles, if he is still offering that service, is Greazzer, the person who posted right above.
Pay to have him do it. He has the experience and expertise to do it right.
I've used him several times and he's always done a great job.

You will be wasting your time and money to try and do it yourself for one set of injectors.

[Bigjake34452]

Ok good to know.. saw a post greazzer made about retiring.. if that’s the case looks like Benz injectors has a decent deal on injectors, about 360$ after core.

Comes with option of 265 or 314 nozzles, says 314 is higher flowing, what nozzles would my 92 have and would the other option be better

[greazzer]

Not fully retired. Lol

Just took down my website

I’m doing sets for forum members

[dieselbenz1]

Either the 265 or 314 work well on the 602 I've run them both and my preference were the 265. When you run your Purge have a look at the return line if any bubbles appear in your Purge bottle then you would have air in fuel problems.

[Bigjake34452]

Originally Posted by greazzer

Not fully retired. Lol

Just took down my website

I’m doing sets for forum members

Oh ok where are you located?

[Bigjake34452]

Originally Posted by dieselbenz1

Either the 265 or 314 work well on the 602 I've run them both and my preference were the 265. When you run your Purge have a look at the return line if any bubbles appear in your Purge bottle then you would have air in fuel problems.

What differences did you notice between them?

[greazzer]

The Palmetto State

[dieselbenz1]

It's been a while now but mostly the 265 were quietest. Performance nothing noticeable.

[Bigjake34452]

Originally Posted by greazzer

The Palmetto State

I emailed you but not sure where that goes , I’m used to the private messaging. What’s the best way to speak with you about possible injector service if you were to be willing to do mine?

[Bigjake34452]

Originally Posted by dieselbenz1

It's been a while now but mostly the 265 were quietest. Performance nothing noticeable.

Ok great info thank you