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1983 240D
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Discussion Starter #1
I've posted about the nightmare scenario with my engine overheating to low oil and my mechanic basically stealing $2500 on a rebuild gone bad. Within 48 hours of picking it up it looses power incrementally but very quickly in a fit of excessive white smoke and im left stranded.

So since then ( a few months ago) I finally got around to pulling the engine out of the car which has been sitting dormant in my garage.



The engine removed from the car, is now nicely bolted to a stand. So where should i start? any ideas? remember, my mechanic supposedly rebuilt the head and block. the car lost power and smoked incredibly before breaking down never to start up again ( but for only 5 to 10 seconds). Engine oil drained out in a qty of only 2quarts... havent checked to see if it has coolant in it since my oil receptacle is a closed one.. i have to pour it back out onto another pan and examine it for coolant and other foreign matter. will do later tonight.

any input is greatly appreciated. :)
 

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5 Speed "85" Euro TD , 5 speed "85" Euro 240D, "79" 5 spd 240D, 5 spd "94" Dodge/Cummins PU
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Well at least you have a nice clean engine to start out on. Do you think you will be getting any compensation depending on what you find? I would start out pulling the pan then the head. The guy that did the rebuild should be holding his breath or at least a little anxious to see what you find. Good Luck
 

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1983 240D
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Discussion Starter #3
I agree. Is anyone familiar with dismantling the OM616? If so what is more or less the easiest sequence of removal for all accessories in order to ultimately pull the head? Anything to look out for?
 

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'82 240D 4-spd
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I just took one of these apart, actually. It's in the process of going back together. I don't have the time this very moment, but I'll follow up this evening with a quick rundown of my disassembly and some of the things I noted.
 

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1983 240D
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Discussion Starter #5
I just took one of these apart, actually. It's in the process of going back together. I don't have the time this very moment, but I'll follow up this evening with a quick rundown of my disassembly and some of the things I noted.
sweet! no rush, I wont start until tomorrow after work around 6pm CST.. I'm hoping to remove the oil cooler/lines/filter&housing/pan.. shouldnt be to difficult and i'm sure it'll constitute as a good start. looking forward to hearing from you. thanks again
:)
 

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'82 240D 4-spd
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Is that engine stand bolted to the oil pan that needs to be removed?
It looks like it might be; there's two threaded inserts in the back of the upper oil pan right at that location. Might have to lower it down to the floor if that's the case.

Anyhow, disassembly of this engine was fairly straightforward. I was pleased with how nicely things came apart when I did the tear-down. Access to the FSM is a big plus. MB has this information online (mostly) at this location. For best results, open that link in IE (the nav tends to break in Firefox).

Here's the (rough) order I went in (with lessons learned where applicable). Mind you I was also disassembling an engine that hadn't been apart in 30 years. Yours might be a little easier to deal with:

1. Remove soft injector lines.
2. Remove valve cover and all attached linkages (be careful with the snap-springs in the end of the linkages, they can really stick bad. Shoot some penetrating oil in the ends before gently prying them off the connectors). Looks like you might already have this covered.
3. Remove hard injector lines.
4. Disconnect A/C lines at compressor, unbolt upper A/C line bracket at front center of cylinder head, remove the two long screws on the right-hand side of the lower oil pan that hold the lower A/C line (be sure to catch the two small nuts that hold the bracket if yours aren't attached to the bracket). Not sure how you got the engine out of the car with the A/C compressor still installed, actually. :)
5. Disconnect glow plug wires and temperature sender wire.
6. Unscrew and remove air-oil separator.
7. Unbolt and remove intake and exhaust manifolds.
8. Unbolt and remove timing chain tensioner and thermostat housing.
9. Break the timing chain (using a pin-style chain breaker tool or similar; if you go with a chisel, be careful you don't hammer too hard against the cam sprocket).
10. Remove power steering belt (the PS pump does have a tension adjustment system; it's a little funky).
11. Remove the banjo bolts holding the fuel lines to the top of the spin-on filter housing.
12. Carefully disconnect the sensor wire at the pointer bracket near the harmonic balancer; it's held on with a 7mm or 8mm nut (it's tiny). You might need to really clear away some grease and grime to see the nut. There is also a clamp that holds the wire at the vacuum pump; make sure to get that one too.
13. Unbolt and remove the cruise control module.
14. Unbolt and remove the spin-on filter housing.
15. Unbolt and remove the PS pump bracket; there should be two hex socket bolts on top and three hex cap bolts on the side. If I didn't forget any steps, you can now lift the power steering pump and bracket, plus the A/C hoses and glow plug harness up and forward off the engine. If I did forget a step, you'll notice the snag pretty quick. :p

At this point the cylinder head should be clear and ready to remove; to get the head bolts out you're going to need a 12mm "triple square" driver bit. I got funny looks when I asked for this at stores around here, so I eventually had to order one. If you've got one already, great.

16. Remove cylinder head bolts; note that there are two smaller (8mm) hex socket bolts inside the front chain gallery. Look straight down in there and you'll spot 'em. Be sure you remove these too.
17. Re-attach front lifting hook to the cylinder head (you probably removed it when you disconnected the upper A/C line bracket), hook your engine lift to the front and rear lifting hooks and slowly lift up until the cylinder head breaks free.

The bottom end is even easier. Once the head's off, rotate the engine around (don't forget a tarp or pile of rags on the floor, there's gonna be oil everywhere), remove all the screws on the lower oil pan, and lift off. Gently drive out the dipstick tube and remove. After that remove the screws in the upper oil pan and then lift it up around the oil pump and off the engine (IMPORTANT: You can remove the upper oil pan this way, but you cannot re-install it because of the front crank seal. You will have to remove the harmonic balancer in order to re-install the front seal later on).

All that should expose the pistons, cylinders, and crank for inspection.

This is probably way more info than you really need; but there it is just in case. When in doubt, consult the FSM! Also, I have one of these still mostly disassembled in my garage, so if you want pictures of anything for comparison or clarification, just let me know.

Good luck; hopefully things are in good shape.
 

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this might not be the very top priority for your situation, but along the way i would make sure the valves are aligned.
 

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5 Speed "85" Euro TD , 5 speed "85" Euro 240D, "79" 5 spd 240D, 5 spd "94" Dodge/Cummins PU
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Might be a good idea to check the timing chain for damage/stretch then if its good remove it without breaking it, after checking your mechanic's work on the sister link of course. Its pretty hard to tell much about the timing chain after its left the engine, unless its really old and trashed. Yours is probably still fine.
 

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1985 Euro 300TD Turbo, 1983 Euro 300TD turbo, 1979 Euro 240TD and 1981 300D converted to euro.
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Within 48 hours of picking it up it looses power incrementally but very quickly in a fit of excessive white smoke and im left stranded.
If the timing is off on the ip this can also happen as i have seen it before first hand.


Before pulling the head i would time the injection pump and getting it runnng long enough to be warm, then i would do a compression test so as to save the time of pulling the head.
 

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1983 240D
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Discussion Starter #11
If the timing is off on the ip this can also happen as i have seen it before first hand.


Before pulling the head i would time the injection pump and getting it runnng long enough to be warm, then i would do a compression test so as to save the time of pulling the head.
Thanks so much for the run-down mrspaz! :thumbsup: very greatly appreciated.

DieselKraut22? I see what you're saying. Will def check the IP and do a compression test. However, how do you explain the large loss of oil? Also as I was breaking down the valves were chattering away extremely loud.
 

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1985 Euro 300TD Turbo, 1983 Euro 300TD turbo, 1979 Euro 240TD and 1981 300D converted to euro.
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Thanks so much for the run-down mrspaz! :thumbsup: very greatly appreciated.

DieselKraut22? I see what you're saying. Will def check the IP and do a compression test. However, how do you explain the large loss of oil? Also as I was breaking down the valves were chattering away extremely loud.
I was under the impression those things happened BEFORE the rebuild.

If those happened AFTER then i would not do a thing to the motor til you sew the shit out of the prick and get your money back to try and fix it. If you start ripping it apart now you might have a hard time getting anything out of the douche that fubared the thing to start with.


No if this did happen after wards then you have to see where the oil leaks are and take pictures even though this IS sounding like a head issue.
 

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1983 240D
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Discussion Starter #13
dieselkraut.. i'm working on some type of small claims on the mechanic. in the mean time though, im focused on getting this thing back up and running. it really was a terrible experience but the great news is this... it will never happen to me again.. ever. :) ive learned my lesson the hard way.

Anyhow, just an update. I havent been working on the engine as often as i want to mostly do to work and a bit of laziness... but today i had the urge to do more. I just removed intake/exhaust manifolds.. there is a lot of oil in the IM.. how normal is oil in the IM?? taking a break at the moment, need to charge up my impact wrench. but i'm gonna hit the belts/alternator/IP etc... hope to have the engine at least 80% bare by tonight. :)
 

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...there is a lot of oil in the IM.. how normal is oil in the IM??
I wouldn't say it's unheard of on an older PCV engine of any type. Lots of things can contribute; increased blowby forcing more oil-laden gasses past the oil separator and into the manifold, the oil separator becoming fouled over time and unable to collect oil mist from the expelled gasses, etc.

It is a concern if the buildup is particularly heavy and sludgy. Not only can this lead to bad times if some of the sludge breaks free and is ingested by the engine, but sufficiently heavy buildup can foul the manifold, starving one or more cylinders for air.

If you find a local machine shop, you can have them hot-tank the manifold and get all that goo out of there. The freeze plugs on either end are standard 41mm (if I recall correctly); the shop should be able to fit new ones for you after the cleaning.
 

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1983 240D
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Discussion Starter #15
the oil buildup in the IM is not what I would call sludgy. but it is quite wet, almost un-naturally so.. i looked into the intake ports on the side of the engine and the ports and valves are extremely wet with oil. The exhaust ports are dry and look normal. Just the usual dry soot although a bit heavy as well.
 

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1983 240D
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Discussion Starter #16
Update: Ok I know the engine had a lot of blow-by when it did run. (Oil Cap would fly off). So it "seems" somehow most of my oil made its way into my intake manifold, ingested through the engine and out the tail-pipe in the form of tons of smoke.. Then the car simply shut off.. How does this happen?? I just checked the Oil Seperator and its respective hoses, its clear, air flows through it fine. The metal pipe that goes down to the upper oil pan?? i blew air through it as well. Air flows through it, you can hear the air in the block, kind of sounds like you're blowing up an air matress.. I'm confused. :-/
 

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Discussion Starter #17
Ok i think i figured it out.. the so called mechanic probably had the cylinders rebored but was not paying close attention to his piston ring size and thus a shit-ton of blow-by resulted eventually breaking me down. if the cylinder wall was not somehow damaged would it be possible to re-ring the cylinders? after honing them of course. :) i sure hope this is the issue. reboring doesnt sound cheap
 

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'82 240D 4-spd
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Ok i think i figured it out.. the so called mechanic probably had the cylinders rebored but was not paying close attention to his piston ring size and thus a shit-ton of blow-by resulted eventually breaking me down. if the cylinder wall was not somehow damaged would it be possible to re-ring the cylinders? after honing them of course. :) i sure hope this is the issue. reboring doesnt sound cheap
Hang on just a bit; rings aren't sized to the cylinders, they're sized to the pistons, and the cylinders are bored & honed to fit the pistons (with the rings on them). You can't "re-ring a cylinder;" you can replace the rings on a piston, but that's usually not a useful operation on its own.

These engines have sleeved cylinders, meaning that there's a steel sleeve pressed into the block, and the piston fits inside that sleeve. The idea is that you have a replaceable wear surface should something go wrong and you need to replace the piston(s). So even if everything has gone completely haywire the block is usually salvageable.

All that being said, I think it may be a worthwhile effort to hang back for a moment and try and figure out just what was done to this engine. You can, of course, just tear it all the way down and shoot for a complete rebuild, but you are looking at some serious money for that.

Did "the mechanic" provide an invoice that showed what he did, or at least the parts he bought/used? It would be useful to know if he did in fact replace the sleeves, pistons, any valves, any bearings, etc. and any machine work he listed. Knowing what was touched (or at least what he claims to have touched) might provide some insight into what's gone wrong and where to really start looking.
 

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1983 240D
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Discussion Starter #19
ok. no not alot of details on what was replaced. he got me good. he didnt document it. he did say it was resleeved with new pistons/rings/ etc.. yes and new valves. but not documented.. embarrassing i know. he really took full advantage of the situation. i've learned alot though. anyhow really hate talking about the mechanic so back to the issue at hand.

tonight i'm working on cleaning more parts and gonna remove what appears to be some type of brake pump?? at the front end of the engine. and the cruise control motor. then the block will at this point be a completely bare long block. i'm very glad to be removing everything since it has 30 years worth of grime on it, ive been able to individual degrease and clean every single piece. its going very well all the parts i've cleaned so far are very nice and clean. wet/dry compression test will be next but i'll have to re-install the starter for that. then a leak down test.. but i have to find an air compressor to borrow.
 

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...he did say it was resleeved with new pistons/rings/ etc.. yes and new valves.
I'm getting a bad feeling when you follow the above statement with this one:

...i'm very glad to be removing everything since it has 30 years worth of grime on it,...
Pressing out the cylinder sleeves and getting new ones in place is going to require the engine out of the car, with the head off, and the crank removed. Just about everything has to come off to get this accomplished (the right way). If you're running into "30 years of grime," then I really have to wonder what happened in that shop.

I would skip the compression test and go right to the leakdown test; this is going to give you a good immediate indicator of what's going on in there. A healthy engine will have around 5% leakage, with no more than 5% variance between cylinders. Worn out can approach 10%. If you hit 20%, there's a serious problem.
 
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