1982 300D Engine Knocking After Injector Cleaning
Hi Everyone,
I just finished fixing one problem only to get myself into another :-). I tried to install some of the new monark nozzles from mercedessource. I tried to be very careful and clean when reassembling the injectors after replacing the nozzles and thoroughly lapped all the mating surfaces with fine sand paper as described in the guide.
One thing I was not able to figure out is how to remove the old crush washers from the engine to replace them with new ones. Because of this I left them there. Any tips on how to remove these would be much appreciated as they seem pretty stuck in there and there were no hints in the manual I received.
In any case the car started up after the air was purged but as the engine rev'd just a bit I heard very consistent knocking, very noticable, so I shut the car off.
Any ideas for what is causing this?
I'm planning on just opening up all the injectors and putting them back together and reinstalling hoping that there was some kind of assembly mistake.
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Possible causes
Hi Andrew, couple quick questions before we narrow down the problem.
1. Did you pressure test your injectors - too high pressures will cause nailing?
2. Have you check injection timing - advanced timing will cause ignition rattle?
3. When was last time you did a diesel purge? Dirty delivery valves on pump can cause injector noise.
Old worn injectors will not exhibit those symptoms because tips are worn and pressures are usually low. Symptoms will show up those when you install new nozzles.
Hey Kent, Thanks for the
Hey Kent,
Thanks for the reply.
1) I didn't pressure test the injectors, I was hoping that changing the nozzles wouldn't make the pressures of the injectors change too much so I did the installation without having the pressures tested. I am thinking of ordering your pressure tester and adjustment shims to do this job correctly.
2) Haven't checked the ignition timing, I figured it was fine before I made the change as the car ran fine.
3) recently did a diesel purge, i've gone about 1 gas tank on veggie so far.
Heat Shield Washer Removal
Hey Kent,
I spoke with your daughter over the phone today and she suggested I post this question to see if you had any suggestions.
I mentioned to her that I couldn't remove the heat shield washers while doing this job even with needle nose pliers. She said that was unusual and they must be frozen and to see if you had any suggestions for removing them.
Let me know!
disregard last question
After talking to Kaia I went at the washers a little more aggressively and got them all out, just took a little determination.
Planning on rebuilding the injectors and taking them to a local diesel shop for pressure balancing.