My 82 240D has recently started making a new noise in the past 1000 miles or so and I can only hear it driving with the windows up (ac on or off).
Ticking sound made with engine hot or cold. Primarily on throttle and most noticeable at lower engine speeds. Does not get louder if i floor the throttle, I can also hear it revving in neutral or park. When i listen to the motor with the hood up or driving against a wall for example it sounds the same as it always has!

I have done the following:

• swapped the injectors with another known good set ( have a tester)

• pulled the vacuum pump and checked the roller bearing and assembly - all tight

• Checked the cam the vacuum pump roller bearing rides on in the engine - looks good and very tiny amount of play if i pull on the bolt head with a set of pliers.

• Checked the oil pump drive bearing - looked ok

• run a diesel purge (sound does not go away running the motor straight on purge)

• Adjusted valves - i do this every year and none were really out of spec

• Checked timing chain - very tight (recently installed a new tensioner)

• Disconnected ac compressor and ps pump and ran engine without them to try and isolate sound - no difference


I am not trying to drive myself crazy, and understand these old diesels make noises. Thing is I bought this car at 140k miles and it now has 185k miles so I am very used to the sounds the motor makes. Oil has always been changed every 3k by myself and the PO and never run low. I am really expecting this motor to have alot of life left!

This one is definitely a new sound. I also realize these motors can make noises for thousands of miles and be perfectly fine. Just curious if anyone has any input.


Videos:

inside vehicle
engine compartment

Your videos are set to private.

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1981 240D 4sp manual. Ivory White.

Fixed thank you

update! I put a screw driver around the motor and listened at various spots. Listening to all the injectors I found #4 injector to be the loudest however i swapped this set with another and it has made no impact on the noise. moving down to the IP - when I put the screw driver on #4 injector / delivery valve union the sound ticking / clacking is much more pronounced and is sharper than the other 3 valves coming out of the IP.

I am pretty mechanically inclined but a little spooked by the injection pump. Should I pull the valve out and clean it? order a new one? try to find a rebuilt injection pump? OR should I just live with the noise?

That thing sure makes a lot of noise. The whole diesel combustion affair makes a lot of noise.

I wouldn't worry about looking into it, you just have to be very clean and precise when you do so. I've taken the pipe fittings off and replaced all of the user serviceable parts in my IP. At the very least, if you've isolated the sound to that one delivery valve, take a peak. Do a forum search for Diseasel's cerium oxide cleaning technique. I'm not recommending it per se, but there are some good photos there for reference. Just make sure you have a new DV crush washer on hand for each pipe fitting you remove. Even one of those, if not seated properly, partially corroded, etc, can make noise. A new spring, can make noise. It's a bit of a crap shoot to be honest, but no harm in taking a peak. Just make sure (as it has been posted 1000x) you do not disturb the two 13mm nuts that hold the plunger assembly in place.

And do report back!


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1981 240D 4sp manual. Ivory White.