There is a sound file of my wife's 1993 300D 2.5 Turbo (124 Chassis, 602 engine) here - www.pauldrayton.com/uploadfiles/dieselsounds.mp3

Could you have a listen to it (the quality is not great, but perhaps you get the picture) and tell me if that is nailing or lifters, or both, or something else?

I've ordered some Diesel Purge to run through it becuase the diesel kleene didn't do anything for it.

When we bought it about 8 months ago it was very quiet, but it's got very loud over the past 4 months or so. Could it be the cheaper oil we're putting in? Should I use synthetic or some kind of additive?

The fuel consumption is good - about 35 mpg, so I am thinking it is not fouled injectors. But, maybe one of the injectors is bad becuase the sound sounds like it is oming from one place in the engine, near the oil cover and injectors.

I've listened with a breaker bar pressed to my ear (like a stethoscope) but couldn't really locate the source of the sound.

Any experienced ears' help appreciated.

Once again, the sound file is here www.pauldrayton.com/uploadfiles/dieselsounds.mp3

If needed, I can get a better quality sound file up there. Heck, I even have a diploma in audio engineering!

Thanks.

Paul Drayton

Here's some easy things to try:

- with the engine idling, very carefully put pressure on the serpentine belt damper. Press on the body longitudinally and transversely and press on the upper mount as well. Those things make strange noises when they're worn.

- with the engine idling, loosen the injector lines one at a time until fuel dribbles to see if you can isolate the noise to a particular cylinder. If you can isolate the noise then it's probably a leaky delivery valve seal.

Sixto

By injector lines, do you mean the metal lines from the IP to the injector, or the rubber fuel hoses?

I didn't mention it becuase I didn't think it was relevant, but there was a leak around the delivery valve seal on cylinder 2 a while back. I replaced the seal and washer on cylinder 1 and 2 before getting frustrated with the difficulty of it all and leaving 3,4 and 5 since they don't leak. There is no visible leaking anymore.

Even though it doesn't leak fuel, could it be a bad delivery valve seal, or am I confusing it with something else?


Thanks.

I mean the metal lines. Also check that the lines aren't hitting each other.

There is a crush washer in the delivery valve assembly that can cause internal leaks with no external manifestation. Those are the leaks that cause noises. You can have external leaks with no noises.

If you have the right touch you can feel the injector lines and isolate the noise. I don't have that touch. And possibly the tech that told me that was pulling my leg.

Sixto

Thanks, I'll try that.

By crush washers I assume you mean the copper washers that go onto the IP under the splined bolt with the injector line. I replaced two of those, but from what you're saying, I might just should have replaced the lot of them. I know I should have, but the injector lines get in the way and it's a PITA. But I have better tools now so it shouldn't be too hard.

That's a lot of work for no purpose if you can't isolate the noise to those injectors.

Sixto

Yeah, that definately doesn't sound like mine. Mine sounds pretty close to normal (at least I like to think so ). A 1990 300D 2.5T with about 93,000 on the clock.

My recording was when it was cold, there's considerably less rattle when it's fully warmed up.

__________________
Dale

http://i52.photobucket.com/albums/g1...MG_2277sig.jpg

1990 300D 2.5 Turbo -155k
2000 E430 - 103k
2014 Jeep Grand Cherokee Ecodiesel 4x4 - 11k
2014 VW Passat TDI SE - 7k Bro's Diesel
2006 E320 CDI - 128k Pop's Benz

Pre-glow - A moment of silence in honor of Rudolph Diesel

I love those sounds of both of those diesel engines.

Mine sounds a little like that, but mine is not a diesel.

How do you get your sounds on here? I have a new camera that I know can operate as a video camera. I wonder if it will record sound only? Do some research on this, because I want to post the sound of my engine here, as I think I have some woes with it.

Good luck with your car, but like I said, I like it. You should have heard my old 74' 240D, it was KNOCKING severely.

Thanks guys.

Sixto, I tried loosening the delivery line nut and the sound was still there for each of the 5 delivery lines. The rpm's dropped, but the sound was still there.

So I recorded it again, this time with video, so you can see where the sounds come from (sort of). The video is here. You can here it a lot better - it's better quality this time. You can also hear there is a sort of after sound when the revs come down, like something is spinning. I don't know much about turbos, but that doesn't sound like it should to me.

Are you sure the clacking is not just the lifters? The sound really seems to be coming from the oil cover, although I can't really locate it.

I'm all for setting the valves if they need it, but don't want to pull off the oil cover for nothing. Is setting the valves hard on these engines? Do I need a special $100X tool???

BTW 86560SEL, the easiest way for you to get sound only from your camera is probably to use the video editing software that came with it (or better software if you have some) to open the original file and then see if you can "Save as..." or "render" as an .mp3 or .wav, or .mov (without video). Let me know if you have more questions on that. Computer stuff I know, diesel engines, now that's a different deal...


The video is here, in case that other link doesn't work http://www.pauldrayton.com/uploadfiles/MVI_2275.mpg

If you've discounted all the external sources then it's probably the hydraulic lash adjusters. Nothing to adjust and AFAIK nothing to clean. I think the procedure is to remove the valve cover then press on each lash adjuster/tappet/lifter at TDC to feel for the one/s that collapse/s. Then pull the cam following carefully the cam bearing loosening and tightening sequence. When you see what's involved, you have to consider the cost of a complete set of lash adjusters ($15-20 each?) vs replacing just the bad ones. Others have had luck clearing the noise by switching to synthetic oil. It can take up to 10K miles on synthetic oil for the noise to clear. Then you're pretty much committed to synthetic oil.

My SDL had some lash adjuster noise even with a new set, but only at idle. by 1500rpm the engine was quiet... well, the lash adjuster noise was gone.

Sixto

I think neither of your cars is right.

Though it's pretty ridiculous to pretend to be able to diagnose any engine in these conditions I'd guess that yours, pdraton, is drawing air into the system and yours, 2.5turbo (the more easily addressed) is in need of injector overhaul to include cleaning and bench pressure balancing. You, 2.5turbo, have a very noticable miss that isn't regular which leads me to say what I did.

Did you, pdrayton, by any chance, do any 'work' on the fuel feed side of your injection pump? The filter or lines to and fro? If so, I'd look first for that air gulping in those areas.

JMHO, and I won't be hanging out for questions.

Well here comes one whether you like it or not

Would running a diesel purge first do any good? Or should I just have the mechanic pull the injectors and take a look? I don't have the proper equipment or know-how to be messing with the injectors. If it's any help it runs nice and smoothly, there's hardly any engine vibration/movement when at idle or at any other speed. No real smoke unless I get the RPM over 3500 flooring it. Do you think it's a timing issue or maybe a kaput injector? I inherited this car from my grandparents and they always took it to MB for anything and everything it needed. They kept complete service records, so I'll have to dig through them and see if there's anything injection related.

__________________
Dale

http://i52.photobucket.com/albums/g1...MG_2277sig.jpg

1990 300D 2.5 Turbo -155k
2000 E430 - 103k
2014 Jeep Grand Cherokee Ecodiesel 4x4 - 11k
2014 VW Passat TDI SE - 7k Bro's Diesel
2006 E320 CDI - 128k Pop's Benz

Pre-glow - A moment of silence in honor of Rudolph Diesel

Thanks KRS.

I replaced the delivery valve seals on 1 and 2, but it was already making noise before that.

I replaced the pre and spin on filters. I'll have a look and see if there's anything else there I might have missed or messed up. Thanks for the pointers.

OK, I'm back for a minute. I'll apologize - I usually whip through sites that interest me as often as I can and am mostly gathering info myself. So I seldom stick around one long enough to be available for followups to my occasional inane posts. I don't like to seem rude but if happens when situations like this one arise.

Anyway, to try an answer for you: not many people are equipped at home to test fuel injectors accurately. The best thing is to look up a diesel shop in your area that specializes in injection (well, ALL diesel shops specialize in injection, but not all have the test bench for setting up a set of injectors. Other shops usually use a local injection specialist for injector work). If you're not confident of your ability to remove and replace injectors by all means use someone. I don't yet know Mercedes quirks but do know enough others to know that there will be pitfalls with these cars as there are with the others.

It shouldn't be much over about $150. to run a set of five although I've seen prices in the neighborhood of $500. from places with a high tech or racing focus. I'd want to find that place that the general repair shops trust and use before somone who promises horsepower or specialty tuning. I'd just want the car to run well - smoothly and without starting or shutdown issues. You can't tell much by looking at injectors, BTW, they need to be put under operating conditions and their squirting output measured and balanced with the rest of the set.

Sometimes a good diesel injection system cleaner can work seeming miracles so they're worth trying. But if they don't smooth the engine after one try then I'd say that more is needed than they can give. Injectors are nozzles with springs that tire and precision orifices that erode into odd shapes and enlarge or shrink by wear, heating/cooling, or gooing up. Every change affects how the engine will run. Injectors are very durable so replacement isn't needed as often as some places would have us believe.

ed: Good thread about injectors : anyone know how to use a diesel pop tester?

There's this:

Not all problems are injector based.The pump can have many similar influences. These are mechanical wearing devices that resemble precision made small engines with cranks that rotate and pistons that travel in cylinders. They are usually rebuildable and many are available online from places that only do that. Id tackle home replacement but won't recommend that everyman try it; it's one of those things that requires an honest assessment of personal grounding in auto mechanic skills as things could go very wrong. But the pumps generally last a very long time and can wait until injector issues are resolved. That good shop including a good dealership shop could go quickly to whatever is the real problem but, boy, once your car is in their grasp.....


pdraton - on the suction side of the pump air can enter at any point back to the fuel tank. The lines, the lift pump/fuel pump, any and all fittings between. It can even get into seemingly good lines, rubber or steel. With steel lines a small bending can result in a tiny crack and with rubber lines there can be what seems to be a sort of osmosis where air enters into the fuel stream right through an apparently good ruber wall. Such leaks often do not show as wet spots since the system suction pressure will draw fuel right along while drawing air in through openings as fuel passes by. consider all of the lines to be old unless you know first hand of a replacement.

Good luck to you both! I love that diesel injector pump clatter and it was a pleasure to find your recordings. Never thought to do that before.

(whew! now maybe a higher understanding of my reluctance to hang around? I talk too much!

I checked the lines as far as I could. They all look good.

so I ran a can of Diesel purge snake oil miracle cure through the car, and it quietened right down. But after 40 miles or so it started clacking again.

So I ran another can through it and it is still quiet now, after a few hundred miles, but I don't trust it. We'll see.

I still think there's something wrong with it - the engine sounds like it is straining. I think I'll take it to the local reputable MB mechanic and hope it's nothing $$$ !