87 300D Injectors?
 

So fixed the clogged cat in this car. Alas, now she will sputter out if I do not keep the RPMs over 1000 until engine temp hits 40C. Also have white/grey smoke until operating temp.

Does this sound like leaky injectors? Time to rebuild?

Could this also cause more knocking than my 87 300TDT?

Thank You!

Geez...sounds like you got it running.... I had the sedan 87 300 D...many years ago...You mentioned injectors here and I think I could add something, but based on your short mention of more detail, injectors may not be your only concern.

Original Bosch injector *made in Germany* made for your OM603, may be near impossible to find. What has been available in recent years are rebuilt Bosch injectors utilizing inferior 'India made' injector replacement parts....Results reported are inability to balance injectors properly inducing rough idle and poor performance. Bosch so far as I know, no longer manufactures the injectors. Many people opt to simply have the old original Bosch injectors taken apart, cleaned and then balanced....Often they are far better than the India rebuilds.

I'm not sure who's on Mercedesshop anymore, but a fellow poster named Larry Bible, could share more light. I think you have other issues going on with your om603....but as always, start diagnostic from the las known issue. Be prepared it may go quite far...

How are your glow plugs? That's would be next to check!

gp, timing, compression

Goofy question. Why glow plugs? I was under the understanding that glow plugs are there to pre-heat the cylinder for that first start when cold. Do they serve more purpose than that?

Winmutt, I will search for a good thread to check the timing.

Thanks for the insight!

Does this IP have the pneumatic idle speed increase system fitted? If so is it working?

You have lots of white smoke until the engine reaches 40 degrees which could likely be glow plugs. Yes GPs are used to assist startup when the engine is below operating temperature.

Tried a purge? Liqui-Moly works really well but can be pricey/tough to find. Seafoam works not quite as well but is $6 a can at sprawl mart.

The 87 does not have afterglow. The glow plugs only run until you crank and that's it.

The OP needs to rebuild his injectors and possibly replace the nozzles.

Perhaps his GP relay is not working so he does not get a glow which would account for his white smoke. Try the simple things first.

Maybe. When I had 2 dead glow plugs the smoke went away after 15 sec and it idled without any throttle input. Its easy to test the GPs by measuring resistance between the 6 pin plug at the relay and GND.
I still think its an injector issue.

Did a diesel purge last weekend. Will post pictures of what is left in the container. Black and yucky!

Went out today and replaced the secondary (screw on) filter. Filled it with diesel before re-attaching. Car started after 3-4 attempts.

Replaced return line from filters to the tank. Old line was very brittle. New line is much better.

Attempted to start again approximately 1/2 hour later. She cranks but does not catch. Could I have introduced air into the system via the return line?

Also, one of my son's was connecting the passenger side headlight. I purchased $100 euro's and they did not have a wiring diagram. My 16 year old got it working!!! (Should not be related but thought I would mention...)

Any ideas?

Happy Monday!

More than likely air. Loosen all the hard lines at the injectors, crank with the accel. pedal held to the floor, as you get fuel at each injector tighten up the lines.

Don't be afraid to crank for up to thirty seconds at a time, the starter is massive and built to take that, but give it about a minute to cool off between cranking.