I'm glad you're not dead sure. I was beginning to get bummed thinking that was it, for sure.

Have you ever used the Harbor Freight leak-down tester? Any other equipment provider you'd recommend? (Since I don't foresee my using such a tool frequently, cheapest is probably best.)

Will do, again. I checked chain stretch last time I adjusted the valves (November '08--the much-despised harmonic balancer method), and it appeared to be 5*. I've not done anything to change it, although I know I should. Only so much money I can put into the car at once.

I hear that. I made the mistake of trying to turn the engine over for a few seconds after I rotated the engine CCW. It didn't fire. Hopefully I haven't busted a valve, as you suggest.

Thanks for all the help!

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'Betsy the Getaway Car' : 1978 MB 240D, 582k
'The Mistress of the Sea' : 2001 Giant Boulder, 10.30k

If you adhere to a "convention," there is no need to qualify the answer. The convention will specify which end is referenced. I believe that SAE J824 is the currently accepted convention. It references the top of the flywheel, as viewed from the rear.

Therefore, the subject engine is a left hand (CCW) rotating engine.

It may be a convention..........and it's certainly "currently accepted"..........but, I'd have to say that it is not in common usage.

Per that convention, your statement is correct. However, I note that it differs markedly from your previous comments.

always.. the motion of the crankshaft pulley.

what do they say about transverse engines?... do you sit on the fender?... which one?

try focusing instead fulfilling your own personal agenda.

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a compression test may also tell you. I, personally, wouldn't buy a new tool just for that either.

You must check again since the incident. If you come up with some absurd number (20*-29* or more) than you have skipped a tooth and the chances are it happened at the crank.

did it stumble and nail? or was there mechanical noises (clanging, banging)?


it will be difficult to rearrange the chain on the crank alone. I have not done this myself.

You have two choices if that is the case; here is a rough approximation of what has to happen each way:


[Time consuming factory approved method] (kinda):

-remove IP (can you get this out on the 616 w/o removing the oil filter housing?)
-set crank to TDC (along with the closest setting of TDC on the cam)
-remove tensioner
-reset camshaft to match crank (requires removal of sprocket and rockers)
-reinstall IP at proper timing.


[Other]:

-set camshaft markings to match the cam tower (approx TDC)
-remove vacuum pump (most likely)
-remove tensioner
-attempt with all your heart to slacken the chain enough to gain that link at the crank and set it to approx TDC. This has to be achieved with absolutely no slack on the IP side of the engine. The chain must be tight on that side.

*There is certainly more human error involved in this procedure and should not be considered if you havent spent much time on these engines or feel at all intimidated by it.*

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In simple terms, if the rear of the flywheel doesn't rotate in the same direction as the clock on the instrument panel, the engine rotates CCW. Are any of my comments in conflict with that concept?

With the engine in the engine compartment I find it much easier to stand in front of the car, looking aft when viewing the visible end of the crankshaft turning than behind the engine to get a view of the flywheel turning. So, when someone describes turning the crankshaft in either direction manually it is less confusing to use the terminology Brian has defined, especially when they note they were using the power steering pump pulley, which is not present at the flywheel end of the engine. To avoid confusion about which clock you are referencing, use the watch on your wrist, or pretend there was a watch on your wrist. That way you can ignore the clock in the car, which on a W123 by now is probably dead still.

Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

I skipped over a lot of the nonsense in this thread so forgive me if it has already been answered, but what you should do is try to rotate the engine by hand in the correct direction a few revolutions. If nothing binds then you should be fine, just start it up.

__________________
1979 240D- 316K miles - VGT Turbo, Intercooler, Stick Shift, Many Other Mods - Daily Driver

1982 300SD - 232K miles - Wife's Daily Driver

1986 560SL - Wife's red speed machine

It didn't light at all, but at the time I still had all of the fuel hard lines disconnected at the injectors. No fuel, no wonder. There was a clicking that seemed to occur with every revolution. There's a chance the sound may have been there before and I have noticed it now that I'm hyper-aware of every sound coming out of the engine. I'll see what happens when I turn it by hand this afternoon.

I think the IP on my engine can come out without removing the oil filter housing. Seems like there's some space. Removing sprocket sounds on target; why also remove the rockers?

Sounds like a feasible method, but I am a little more hesitant on this method than on the one above. Probably has something to do with the advisement to "attempt with all my heart."

All of this is a great starting point. Thanks for your help. I'll have the new chain stretch this afternoon.

__________________
'Betsy the Getaway Car' : 1978 MB 240D, 582k
'The Mistress of the Sea' : 2001 Giant Boulder, 10.30k

unless you are confident in your ability to rotate the camshaft controllably with the force from the valve springs present... you will need to remove the rockers.

It just simplifies the process by gaining you control over the situation.

I suppose you could set the cam to TDC and pull up the slack on the IP side by rotating the crank.

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Update:

Aligning the marks on the cam tower, the harmonic balancer reads about 7* ATDC. Before turning the engine CCW, the reading was 5* ATDC. This difference is not very great; is this good news, or might there still be a problem syncing the valves with the crank?

Also, after hand rotating the engine a number of times with the valve cover off, I still have not heard any unusual sounds. Periodically the engine builds up pressure and it gets hard to turn, much like the last couple of times I adjusted the valves.

__________________
'Betsy the Getaway Car' : 1978 MB 240D, 582k
'The Mistress of the Sea' : 2001 Giant Boulder, 10.30k

That sounds pretty good.

especially if you can rotate the engine as BGKast mentioned without binding.


the only thing that concerns me is the clicking. Thats up to your discretion whether its a valid fear.

If it is:

you could remove the manifolds, and use a light source to determine if there is a broken valve.

Or compressed air into the injector holes with a blowgun and rubber seal.

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You may have just heard the IP timing device clank...the springs in it made such a noise when I put the new chains on the 240D and my 300D....

( jt20 ) also reminded me the vac pump spring makes noise too if the rollers fall off into the track recess when this stuff is moved manually....that is probably what I was hearing when I was rolling on my chains.....

If the index mark on the cam is ok with the crank mark...that relationship is ok

You could also do a quick drip timing test to compare readings...If all of these are close to spec I would attempt cranking normally....

I did this also a couple times and nothing happened bad....but I did worry...

Of course all precautions to insure everthing is as right as possible is always good advice....

as for direction of rotation...
On my 240D...

If I stand in directly front of the 240D with the hood open looking at the engine...
The crankshaft,camshaft, IP and all belt driven accessories rotate the same direction a clocks rotation would be if the clock was velcroed to the front bumper facing me...

__________________
1978 Yellow 300D (The Mustard Toad)
1980 Blue 240D (The Iron Toad)
1989 Grey Mitsu.4WD Mighty Max Pickup (Needs a Diesel transplant bad)

(Open the pod bay doors HAL)

Short version:

Turning the engine by hand I see that twice per revolution the chain puts enough pressure on the rail to push it very quickly and significantly against the tensioner before allowing the rail to pivot back to its usual position. This pivoting motion is very quick (less than a second) and occurs near TDC and BDC for cylinder #1.

I don't recall seeing this before; is this normal operation for a 616? What might be going on here? Any perspective on this would be quite useful.


Long version:

After turning the crankshaft CCW a few weeks ago, I found that my timing went from being 5* off to 7* off, so I decided to decided to do something about it. Yesterday I put in a 5* woodruff key (I've read that there is a 6.5* key, but I couldn't find it anywhere online or with the local dealer).

Turning the engine by hand, I noticed that the timing is still off by about 5*. Just before TDC and BDC for cylinder #1, I've noticed the following behavior:

# The engine becomes difficult to turn, and the chain puts additional pressure on the rail, causing it to pivot against the tensioner a little.
# When the engine is most difficult to turn, rotating the engine a little causes the chain to put a lot of pressure on the rail, which pivots significantly, depressing the tensioner more than usual.
# The rail quickly pivots to its usual position and the engine is very easy to turn.

The pivoting action is very quick, like a hiccup. I don't recall seeing this before, and it seems like something that could be destructive in an engine running 4000 RPM.

Some additional details:

# Didn't remove the glow plugs or injectors. I know that compression is at its highest at TDC for cylinder #1 (not sure about when peak compression occurs in other cylinders), and that the engine should be difficult to turn then, but this engine has high mileage and lots of blowby--it's never oscillated so severely between being easy and hard to hand-rotate.
# Put the valve cover on and kicked the starter a couple of times. No calamities, although the car wouldn't start, and the chain behavior still seems unusual.

Any insight into this would be most appreciated.

__________________
'Betsy the Getaway Car' : 1978 MB 240D, 582k
'The Mistress of the Sea' : 2001 Giant Boulder, 10.30k

Will someone make a freakin' picture? Will it suffice to say he rotated the engine 'backwards'?