No change is sound when loosening the injector lines. Any issues with the internals of the engine are not too suspect. As the source of the noise. As regards the pistons and bearings.

Chase one problem down at a time is less frustrating. I would locate the noise that disturbs you first. Sometime an extra set of ears from a friend can help.

A very incidental thing to remember is to make sure the boost line to the turbo is clear. Later at some point. You get an old car that has just been driven with nothing really done. Even for decades sometimes. It can be a chore to get it all.

Sounds like fuel starvation either from linkage issues. Or the overall fuel system needs going over. Takes more time than money usually to do that.

Something that I have never bothered doing. Removing the fan belt could reduce the background noise somewhat. As an aid in finding a noise I suppose. Running the engine with no water pump working is not going to hurt it for a few minutes at idle.

You have a switchover valve connected to the ALDA; it prevents overboost to the turbo. If the plastic switchover valve hoses are disconnected, connected to the wrong nipples, or if the switchover valve has gone bad, you will get no power. I could not get my '81 300SD over 30mph at full throttle when mine went bad. New one was maybe $25. Pictured below at center right. It looks like a metal cube with a nipple on the top. Attached to the firewall on my SD.

It does dance, and even jumps a little--but it doesn't blow off. From that I'd say there is a little blowby, but it's not at the end of the road.




I think that particular pivot mechanism is ok, at the very least the accelerator pedal can move the linkages far enough to engage the kickdown button. But it seems likely that my linkages are all out of whack, everything seems to be "hanging" off the linkage to the injection pump--and the IP linkage can't move anywhere close to its maximum extent. But I'm not going to get into the linkages until I understand them a little better.

Edit: Wise to not just start adjusting, the linkage is hanging up on the cruise control, not the injection pump. Yikes, what a mistake. In any case the cruise control linkage is clearly wrong and may be interfering with other linkages working correctly--and possibly preventing full travel on other linkages. I feel like I'm probably safe to adjust that one.

The valve in that position on my car is round. I will check it, thanks for the tip.

I think I may have found the answer.

Testing how it would react to having a new oil filter in and adjustment to the cruise control linkage, I took it for a spin around the neighborhood. Oil pressure was good, power as good as it's been. About 3/4 of a mile into my drive I got a loud pop and then silence. Bumped the transmission lever up into neutral and tried to restart--wouldn't crank. Coasted to a stop almost in front of my driveway, wouldn't crank. Got the kids to help push it the rest of the way into my driveway, and I can't turn the engine from the power steering pump.

There are no leaking fluids, it didn't bust the block--even so my best guess is a rod let go, and is now obstructing the engine from turning.

I would love advice as to anything else it might be, or ways to confirm/rule out, when the engine can't be turned by hand or with the starter.

Were there any metal flakes in the old oil when you drained it?

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Milan Brown 1979 240D, rebuilt OM617.952 turbo diesel, rebuilt 722.315 transmission (my only daily driver)

Instagram: @maximed93

Hope not. Terrible news.

I didn't notice any. The oil was as black as I've ever seen, though.

Oil is going to be black because there's a certain amount that didn't drain, particularly that which remains in the oil cooler and lines running from it to the filter housing. It's not a big deal but it bothered me enough to install stainless steel lines between the oil cooler and the hard lines so I could drain it and never worry about rubber deterioration again. It cost 125 bucks to have them made.

You may have a vacuum pump problem. The sound you described in the first post gave me pause but unfortunately I didn't read it until this morning. Pull the valve cover and check the timing chain and cam shaft for damage.

First things first here, OK?

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84 300SD
85 380SE
83 528e
95 318ic

On a 617.952 if you read in the tech manual how much Oil you need for a new Engine and how much oil you need for an Oil change there is at least a quarts difference in those. That implies that there is at least that amount un-drained out of the system during an Oil Change.

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84 300D, 82 Volvo 244Gl Diesel

Odds are very high the failure has to do with the timing chain. You had no indication of any noise change when you did the injector line test. This caused by vacuum pump, really worn and weak chain or part of a chain guide. Or even a stretched chain and worn out chain tensioner.

These cars exceeded expected lifespans of gas cars engine wise usually. At least for cars of that era. As the miles and time accumulated. Owners and garages tended to not be aware of what are milage related wear issues. That required periodic checking.

A very large component is also infrequent oil changes. Just throw another quart of oil in instead. The amount of abrasive soot just goes on building up. The timing chain tends to suffer most under that situation. Anyways I am sorry to hear of your misfortune.

In a way one has to consider the upside. It did not occur out on a freeway involving all kinds of issues and perhaps a heavy towing bill. That is still little consolation I know. Life at my advanced age has taught me that on average almost any situation can be worse. It kind of goes with the territory.

About right for the retained amount in the lines to the oil cooler and the cooler itself I suspect.

I will check on the condition of the timing chain and report back. I guess the best case scenario would be if the vac pump bearings dropped into the timing chain and stopped the engine without busting anything. In that case I could pull out the offending bit and carry on grooving. Would of course need to replace the timing chain, tensioner, and vac pump.

I'd be surprised if I'm that lucky, far more likely it broke the chain and what's stopping the engine turning is valves. But even that's probably better than a broken-off rod, which was my first thought.

There are guys on here much more experienced than me, so I will defer to their judgement, but if you're looking for more ideas...

I personally drive a '77 240d, but my girl's gas powered '01 toyota camry timing belt snapped awhile back. I replaced the timing belt and timed it, turned on the car, and heard knocking very similar to what you posted in the youtube video. Eventually i dropped the oil pan and found that a bearing had exploded, evidenced by chunks of curved metal in the pan. Nothing went through the block, but I couldnt tell what happened until i dropped the pan. Messy, but something to try if you're desperate.

Good luck!

(never mind - I posted this before I read the OP give the more recent update)


could it be the AC compressor smacking around and around with a broken/stuck clutch? def doesn't sounds like air filter. Take the compressor belt off (if you aren't using compressor/AC at all maybe just cut the belt off.)

sounds kinda cool though (but I agree not healthy)

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Andrew
Montclair, NJ
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1982 300D Turbo
120k
Petrol Blue Green