617 vibration dampeners: Is the difference US vs. Euro spec or Turbo vs. NA?
 

I am talking about my Euro spec 1984 300D with a normally aspirated (non-turbo) 617 motor. A few months ago the front pulleys and vibration dampener fell off when I was driving about 70mph. I shut the car down real quick and pulled to the side of the road. Broke my fan, and the flying broken fan blades shredded the radiator. The car didn't overheat, unless you count the retained heat after losing most of the coolant.

To be clear, I am trying to stick to Mercedes terminology: the vibration damper is the piece that looks kind of like a brake rotor, it is sandwiched between the lower pulleys and what Mercedes calls the balance plate. The balance plate is held on to the crank with a big center bolt and two dowel pins.

No problems with the balance plate attached directly to the crank, it stayed solidly in place. The six bolts which go through the lower pulleys and the vibration damper sheared off.

The vibration damper and pulleys stayed together (rust) and remained in the engine compartment, the belts kind of held them up. I had the car towed home, and when I took the vibration dampener/pulleys loose from the belts and out of the car, a few of the bolts fell out of the middle of the pulley. some of the bolts were sheared, one was full length but mangled.
The vibration damper itself looked pretty bad to me, all 6 bolt holes were ovaled, some more than others, the bolt holes also showed thread marks, like the disk was wobbling loose for a little while before it came off.

My running 240D was out of order with a busted axle, and I had a another 300D parts car sitting, so I figured I could swap the vibration damper from one 617 motor to another 617. Not necessarily so! The vibration damper disk that fell off of my 1984 Euro spec, non-turbo 617 turned out to be thicker and more deeply “dished” compared to the damper that I took off my 1982 US spec, turbo 617.

The crucial difference between the two is the depth: the bolts that held on the US turbo version were M8x_ , the bolts that held on the Euro non-turbo version were longer: M8x45. As well it’s more than a matter of just using longer bolts. The balancers are different, the US turbo vibration damper is not deep enough to seat down flush to the bottom of the recess in the center of the Euro balancer. If I were to cobble together a bolt length that “worked”, I’m sure that I would shear those bolts off very quickly.


More bad news, when researching the FSM and online I saw that The blts were supposed to be allen head cap screws. The remaining bolts that I found after losing the vibration damper/pulley from the motor were 8mm allen head but they weren’t cap screws, more of a round head.



I decided to get the old sheared off portions of the bolts out of the balancer plate, there were three stuck in there. I was able to just spin two out by catching the broken edge with a screwdriver. The third was stuck in there real good, I center punched it and tried to drill it with some pretty decent drill bits, really didn’t make a mark, just made it shinier.
I examined the old bolts and thought they looked a lot like stainless steel. I looked at the vibration dampener again and noticed what looked like some orange junkyard type markings. So I guess this isn”t the first time the vibration damper fell off the front of this motor.


I put the “original” vibration damper back on the motor, even though I had my doubts about it, and drove very carefully for the next three days until my new axle came for my 240D. The day after I parked The 300D I found half of one the bolts in the parking lot at my job. I thought that I might have over torqued one bolt when I was getting it together, I used a torque wrench and paid attention to the specs (35Nm) but I thought I felt one twist and give, the spot I was working had a lot of traffic noise making it hard to hear a click and the position I was in made it hard to feel the click.


I feel very fortunate to have made it through those three days without doing any further damage.


The question: is the difference in the vibration dampeners a Euro vs. US difference or a turbo vs. non turbo difference? Anybody ever take apart the front of a US non-turbo motor? Does the vibration dampener on the right look like the vibration dampener on a US non-turbo motor? If so I should be able to find a part fairly easily that will fit.


Anyone ever take apart a Euro spec non-turbo? Does the vibration dampener on the right look correct? Because with the stainless steel non standard screws being used, I do have to wonder if this is the correct part for the motor or if it’s just something the previous owner thought would work.


I am optimistic that a US non-turbo 617 may have the same vibration damper as my Euro 1984 non turbo 617. The one shown in this Ebay listing looks similar.



Mercedes W123 OM617 Non Turbo Harmonic Balancer | eBayAttachment 113587

Attachment 113588

NEITHER of those pulleys are from a turbo motor... all the turbo engines had the dual pulley alternator drive...

I have both NA 617, and a turbo 617 from and 85 car long blocks sitting on the floor of my shop... I'll see if I can pull them and compare for you.

I know there are crank differences between the NA and the A 617, the oil pump is chain driven on the turbo... it would make sense that the balancer would be different as well, since the block is nearly the same, they had to make up the change somewhere... also, the turbo would need the mass to decrease turbo lag, but I thought they would do that on the flywheel...

Thanks vstech, this is the first time I put pictures up on PP, so it it's worth ezplaining that the two pics at the end of the post are views of the two styles of vibration damper I have on hand. In both pics the one on the left came off my !982 US turbo 300D, on the right is the one from my 1984 Euro spec non-turbo 300D.

The ebay link is to a vibration damper (harmomic balancer in ebay listing) from a 1981 or earlier non turbo 617 motor.

um, I was upside down when I looked at the pulleys... but now I understand better...

however, looking at your pictures, it appears you have the turbo pulley on the right balancer, and the NA pulley on the left balancer.
simply from the standpoint of dual groove alternator drive...

the pulley onthe righr in the pictures came out of my 1984 Euro spec non turbo 300D. It's a non AC car as well as a non turbo. this would explain the number of pulley grooves, two close to the vibration damper for the alternator, one on the outside for power steering. BTW my 1984 Euro spec non turbo 300D is also a manual trans. One reason I bought the car was to get the more massive flywheel that goes with the manual trans.

The 616s really don't have much of a vibration damper, so maybe the addition of a vibration damper on the 617s was so they could continue to use the older design flywheels.

But my question really is: Is the vibration dampener on the right in the pictures the same as a US Non Turbo 617 motor?

I need Stretch to weigh in on this, He's taken these motors to bits

Here's another clue. The bolts that sandwich the vibration damper/pulleys to the balancing disc are longer on my Euro spec non turbo 300d: they are M8x45.

The bolts that held on the vibration damper/pulleys to the balancing disc on my 1982 300D are shorter (M8x30?)

Anyone ever remove the vibration damper/pulleys from a US non turbo 617? Do you remember what size bolts?

If you look at the diagrams in the FSM for the 300D N/A and the 300D Turbo you can see the difference in vibration dampers. The turbo damper is flat, the N/A is deeper.

The balancing disc is also different.

N/A indeed uses M8 x 45
Turbo uses M8 x 30

There should be no difference between US or Euro engine, there is a difference between turbo and N/A.

The damper on the right does indeed look like a N/A.

Thanks Grovert. My FSM is a North American edition dated 1991. I wasn"t able to find a comparison in mine.

Do you want part numbers?

I can dig some stuff out of the garage tomorrow if need be (that's in about 8 hours from the time of this post where I am)

You can also try getting in touch with 1960mog he's done loads of stuff on these engines (more than me).

X2




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Whilst finding these parts is part of the problem, the biggest trouble you are likely to have is to find a way of locking the flywheel so you can apply that monster torque to the 27mm across the flats headed bolt. This is a crucial part of the job to stop things from falling off

Hang about that's not the bit that's falling off is it.

I think you need to check to make sure that that is good though.

Have you looked at the pulley with the engine running? How straight is it?

sorry, Stretch, just got in from work.

You have a good point about the big main bolt holding the balancing disk onto the crank. After I replaced the old (same that fell off) vibration damper I did notice a wobble in the pulley attached to it. not as bad a wobble as I expected considering that all 6 mounting holes were ovalled and I thought I might have sheared one bolt (later confirmed when I found half of that bolt in the parking lot at my job.

Now, with the damper and pulleys removed again, would be a good time to run the motor for a few brief moments and check visually for any wobble in the balancing disk itself, although being irregularly shaped it might be harder to detect, I'll pick a good high or low spot and hit it with a little dab of paint, I might be able to follow that spot.

I'll look more closely at the installation of the balancing disk and 27 mm bolt for signs of replacement/butchery. I am optimistic that my problem is with the vibration damper not the balancing disk.

I remember you had a poll about harmonic balancer failure. For my failure, which is only partial I would nominate overtensioning of the belts as a possible cause. In the US most of the belts sold aftermarket are slightly too narrow, I guess because the manufacturers want to sell what they are already making giving a nominal metric size to a belt designed to inch standards. The belts continually get looser, and the tendency (I have) is to keep cranking them tighter. after getting in there and seeing how everything goes together I have a lot more respect for the lateral force an overtensioned belt would put on the pulleys and thus on the bolts attaching the pulley/vibration dampener.

From the evidence: 1. non standard stainless steel (dumb) bolts 2. junkyard paint marks on the vibration balancer, this will be at least the second time the damper was replaced.

When I found that I didn't have the part on hand, I really kind of backed off of the job. I was afraid that I would be searching for this part in Europe. I've never worked on a 123 manufactured before 1982 and that was part of my hangup. It took me about 6 weeks of turning this over in my mind to get to thinking that this was a turbo/non-turbo issue rather than a European market/US market issue.

Based on appearance and the feedback from you, vstech and grovert, I'm fairly confident that an earlier US market vibration damper will fit.

If you have easy access to part numbers it could be helpful, I have looked and not found any numbers on the part I have, cleaning it up might help.
The Mercedes people here are reluctant to do anything with a car imported outside their system, but I do have one friendly parts man who might look up the number and tell me what US market cars used it.

To help me evaluate the condition of a used vibration damper, how snug do the 6 8mmx45 bolts fit in the holes through the vibration damper? I only have experience with the two I've removed; the ruined ovalled one is extremely loose fit through the 6 holes, but the presumably good one from my 1982 turbo parts car calls for the same diameter bolts and the fit through those bolt holes is also far from tight.

Thanks for your help man, not just today, you've been a terrific source of information over the last 5 years.

I think that the damper on my 84 euro 300d n/a looks different than the damper on my 79 300d n/a U.S version. It is too dark to check right now, but I remember noticing differences... I vote for seized or dragging bearings on accesory belt driven components for example a/c compressor and alternator bearings as a possible cause for balancer problems. In my case a/c compressor was tested by hotwiring the clutch to come on with engine running....it was seized and stalled the motor when we touch the wires to power. The next day on the way to work the damper failed.

Thanks. appreciate it if you could check it out when you have a chance. Looks like a part number would be useful before I start buying used parts online.

Number from Russian EPC
 

Here are some numbers form the Russian EPC (found via EverythingBenz - Mercedes-Benz Forum and Web Search Using Google)

http://www.peachparts.com/shopforum/...1&d=1374730578
http://www.peachparts.com/shopforum/...1&d=1374730585

Is it possible that those parts in your picture are both from North American models 617turbo and 617 n/a and the euro 617 is different than both of those in your picture? The one on this 617 euro motor looks smaller than the ones in your picture I just looked at the euro and it seems to me that this euro one has a thicker crank balancer and a smaller diameter balancing disc. I wonder if someone tried to use a north American model 617 balancer assembly to fix your Euro 617. I can confirm the North American model 617 N/A in the A.M.... but I am pretty sure that the balancer on that one is different than this euro part. Are you sure that you have a Euro motor?

According to the German FSM the 300D N/A got a different (smaller) vibration damper in 1982 (from VIN 123130..298284)

That vibration damper includes a pulley.

According to the FSM the new vibration damper can be installed on old engines, but no mention if the old damper can be installed on new engines.

Parts numbers are A6170300103 for the old damper, A6170300803 for the new one.

There might also be a A6170300403 for very old vibration dampers (pre 1979) but that part number isn't listed for US models.

The thing I don't understand about Mercedes bureaucracy is that they specify an engine specific part at VIN level rather than the more precise engine number level...

(Oh and well done for looking up the part numbers Govert!)

They do both, depending where you look. VIN and engine number are linked together.

Here are the engine numbers for 0103

http://i185.photobucket.com/albums/x...atiedemper.jpg

And here for the 0803

http://i185.photobucket.com/albums/x...tiedemper2.jpg

^^^great stuff now that is handy!

(I've been saying it for years but I think I am actually going to pay the European subscription for EPC and stop being cheap - Russian EPC is all well and good but it is pretty limited)

Membership of an "official" MB club (more info for clubs in Holland: http://automobiel.mercedes-benz-clubs.com/) comes with free subscription of the EPC, but that could be more expensive than the direct subscription fee for the EPC.

Thanks Stretch and Govert for the part number info. I actually paid Startekinfo for worldwide EPC info a few years back and had no luck at all accessing the website. Perhaps now that I have a more up to date computer, I'll try again.

Stretch, I appreciate your gentle humor in the link name:)! One of the things I've admired about you while reading your posts is that you combine knowledge with patience and good humor. Sometimes the information cost (time and confusion, what/who to trust) of internet searches just overwhelms me.

macdoe, the scenario you describe of an oddball part jerry rigged to make do is exactly what has my head spinning. Going to the link Stretch provided for EPC it does seem that the European and US part numbers for non-turbo motors match.

I have to go to work for one of my long shifts, so I just had about 10 minutes to scan all these replies. Tonight or tomorrow I'll really get into it and get started on my part search for purchase.

macdoe, Did you get a chance to compare your two cars? I'm interested but not in a big hurry. Your point about the 79 North American and the 84 euro being different seems to be confirmed by Govert in post 17 and 19 in this thread. I've got to do some more research in The EPC, and find out if the balancing disk that he vibration damper bolts into changed in 1982 also, before I spend my money. Thanks for pointing the difference out, I might have jumped a little early without your and Govert's help.

Yes, looked at the damper in the 79 and it is different than the 84 euro motor. Hope that helps you out. I am not really familiar with this euro car. It just got delivered on Tues.

Here you can see the different set-ups:

Before 1979

http://i185.photobucket.com/albums/x...979om617-1.png

Between 1979 and December 1982

http://i185.photobucket.com/albums/x...t1979om617.png

After December 1982

http://i185.photobucket.com/albums/x...t1982om617.png

The bolts for the Vibration damper remain the same.

As said, the post-1982 version is backward compatible.

Thank you macdoe and Govert. Based on your observation and information it does seem that my schwingunsdampfer on my 1984 Euro spec 300D was replaced with an earlier model North American market part, just like macdoe guessed (good call, macdoe.)

I am going to check with my friendly MB parts man just for kicks to see how much the correct one costs new. that's if MB's software will let him access and order the part from the US.

I suspect that I will probably end up using an earlier (79-82) North American version used part, just like the previous owner did. The original part supplied with the car obviously failed and was replaced. I have to think that perhaps a reason for the failure of the replacement was the use of non MB stainless steel bolts (brittle).

I have some time off Monday and Tuesday I'll get a battery in this car and spin the motor a few times to see how the bare balancer looks as far as looseness/wobble as Stretch was legitimately concerned about. I am hoping that I don't need to replace that part also.

As well I will have to figure out how to check the torque on the 27 mm bolt holding every thing on the crank. I don't have a torque wrench with that high a value but I know there is a formula to figure torque using a longer (cheater) fulcrum on a torque wrench, I'll have to dig that formula up.

Govert, thanks for posting the diagrams from the German manual. Nothing like it in the North American market FSM since non turbo 617 motors were not available here in 1982. Plus now I know that I am dealing with a schwingunsdampfer !

I think the root of the problem is the knucklehead who used stainless bolts, not you over tensioning the belts. Stainless bolts are only around grade 4 or 5. No wonder they sheared.

Hi. A few comments:
I had a euro spec 300 NA motor some years back which ran good but had a wobbly HB. When we took it apart the nose of the crank was buggered up. Putting on the HB on these engines is tricky business and often damages the front of the crank and the circular keyways. I would be very suspicious of your crank nose being damaged in this way too, so I recommend a very close examination of it by a machinist if possible.

In my case we sourced a US spec crank and used that as a replacement.

In the search for the correct crank we had the chance to sit a na block and a turbo block side by side and found a great many differences. IE the nose of the crank on the turbo motor is longer (and perhaps larger diameter too but cannot remember for sure on the diameter).

The non turbo motor uses on belt and its wider than the two belts used on the turbo motor so it will always slip if you use the narrower belt.

Good luck!

Whilst I encourage you to investigate and check the run out of the bits on the end of the crank I'm not too keen on the idea of re-checking the torque of the 27mm bolt.

I think that so long as the parts on end of the crank are running true I wouldn't mess with that 27mm bolt. To do the job properly you need to have a flywheel clamp => I only managed to torque up my 27mm bolt because the engine just so happened to be out of the car with out the transmission fitted.

http://www.peachparts.com/shopforum/diesel-discussion/284511-has-anyone-ever-made-good-diy-tool-lock-om617-flywheel.html

In your situation it will be difficult to make sure that the flywheel doesn't spin if you are not using a gucci flywheel lock.

To check for the "running true" of the bits on the end of the crank you could do it this way

http://farm7.static.flickr.com/6223/...ce69e806de.jpg

or this

http://www.toolsdirect2you.com/media...0000ACTION.jpg

Obviously these are pictures showing measurements of parts not found on an OM617 but I hope you get the general idea

funola, t walgamuth, Stretch, thanks for the help.


Funola:



"I think the root of the problem is the knucklehead who used stainless bolts, not you over tensioning the belts. Stainless bolts are only around grade 4 or 5. No wonder they sheared."


I absolutely agree that those stainless bolts were a terrible idea. But based on 1. Non standard bolts 2. Junkyard marks on the schwingunsdampfer 3. Macdoe’s visual comparison of his cars 4. Govert’s images from the German FSM, this is the second failure (at least! It’s a 300,000 mile car.)


See t walgamuth:



" The non turbo motor uses on belt and its wider than the two belts used on the turbo motor so it will always slip if you use the narrower belt."


Yes t walgamuth, I was using the wider belt 13 x 1030mm. But I’ve been using cheap belts, O’Reilly’s, Autozone, Advance. I’ve ordered some Contitech belts and am hoping they are a better fit.



The one 123 I have owned that was dealer serviced with the receipts to back it up is my 1982 300D (Us spec, now a parts car) That car is a turbo and had the double alternator/water pump belts. I pulled the alternator out of that car and cut the belts when I did (they were at least 10 years old when I cut them) but I wish I kept them just for reference. The Mercedes star belts were not notched, and they seemed thicker in depth, fit very well in the pulley groove all the way to the bottom.



Do you have any experience with the Continental/Contitech belts? Or do you think I’d be better off ordering through a Mercedes dealer? My understanding is that Continental was the OEM supplier, but the way parts businesses have changed, that’s no guarantee that they still manufacture/sell the same design or quality part.



"Putting on the HB on these engines is tricky business and often damages the front of the crank and the circular keyways. I would be very suspicious of your crank nose being damaged in this way too, so I recommend a very close examination of it by a machinist if possible."


Yes, this is my fear. I think that Stretch’s method of checking for “running true” is something I could do myself. My funds are limited and I originally bought this car to eventually use the flywheel, driveshaft, and differential inorder to swap my 617 turbo motor into my 1982 blown motor 240D.

Driving the 1984 300D Euro spec around I was really impressed by how drivable and smooth the combination of the non turbo 617 motor and manual trans is. If this motor is still in good shape, I’m inclined to swap it instead. Less to go wrong, and plenty of power for me, both in passing/merging and top speed.

On the other hand, if the crank/balancing disk is fried, I guess it would be time to go ahead with the swap I originally had in mind: turbo 617 in front of a 4 speed manual trans.

Stretch:


"I wouldn't mess with that 27mm bolt. To do the job properly you need to have a flywheel clamp"



Yes you are right, I wasn’t thinking about locking the flywheel, even with the car in gear, I’d probably get the entire car rolling. Though I might try it in reverse and backed up against a wall or a curb :) then I might only spin the tires on the pavement:)


Just kidding, the dial indicator test seems like an adequate test. I need to see if I can borrow one and check to see if there is enough continuous flat surface on the balancing disk to contact. If not I could always mount the schwingundampfer and read off of that, right? I think that might be an easier setup.


Regarding your thread on the flywheel lock, did you ever check out this thread?


http://www.peachparts.com/shopforum/diesel-discussion/150588-weird-main-pulley-failure-help.html#post1142058


post 6
" The only trick to getting the balancer off is loosening the big bolt. The balancer should have a couple of cutouts. One option (per FSM) is to jam the balancer with a chisel or 1/2" extension bar through one of the cutouts. Use a wrench with a long handle, 24" at least. Once the bolt is out, just pull the balancer off with a generic balancer puller. Autozone will lend you one for free."""


Post 32
"I was able to draw the balancer all the way on without the crankshaft turning. When it was time to apply the final torque of 270-330 Nm, I jammed the balancer by placing a 1/2" extension bar through one of the balancer slots and underneath the upper oil pan lip. This is exactly what is illustrated in the engine service manual for my year model ('82.) (Yes, the manual actually shows a picture of a 1/2" extension bar through the balancer.)

For earlier models with the 722.120 transmission, the service manual calls for the use of a tool which appears to lock the flywheel. Maybe those vehicles have a different balancer without the cutouts. My balancer had a rounded notch into which the extension bar fit nicely."


I have been unable to find this method in my “Service Manual Engines 615, 616, 617.91” Mercedes-Benz of North America, Inc. 1991, book, that doesn’t mean it’s not in there. Also it may be in an earlier edition of the service manual and not in a later one.


And not everything in the FSM is accurate or complete. In the section 03-340 Removal and installation of pulley, vibration damper, and balance plate, right at the beginning of the section it specifies an M8 x65mm bolt(s) which best I can tell are NEVER used to mount pulleys on the 615/6/7 series motors.


Worse, I followed the torque values listed for that bolt which I later found was about 45% higher than Mercedes generally calls for for a bolt of the correct size (M8x45) on my car. I think I mentioned above that I’m pretty sure that when I reinstalled the beat up schwingunsdampfer for a few days, I snapped a bolt while torquing down.


The parts diagrams and lists do show the correct bolt for my car (M8x45) but none of them show the correct bolt for a turbo 617 (M8x30), nor is there a diagram for the pulley/damper/disc setup for a 617 turbo.


So I would not immediately assume that it is “no longer recommended” just because it no longer appears.

The OM617a Turbodiesel had a seperate FSM for the engine, so that the diagram isn't in your FSM for the OM615/616/617.

wow, I never realized that, I just switched from using the FSM on cd, to using a paper copy. I never really cared for the navigation on the cds, and the quality of the pictures on a screen always seemed murky, although on the plus side a screen view allowed me to zoom in for a closer view.

I thought I had all the books I needed, but looks like I need at least a couple more: a 617 turbo engine manual and a European market 617 engine manual:)

There is a better navigation for the FSM, which can be seen here:

Model 123 Maintenance Manual Index

yes, that is much better.

I did find the picture of the 1/2 inch extension used to jam the vibration damper to loosen the crankshaft bolt; I attached a copy here, not the greatest image. I wonder why this is recommended for some transmissions but not others?

I didn't even look at the car Monday or Tuesday. I am still optimistic that I won"t have to deal with removing the balancing disk from the crank. And still turning over in my head whether or not I should settle on using the 79 to 82 version of the schwingunsdampfer or hold out for the later post 82 part

In the German FSM there mentions that the later oil pans were reinforced, while the older ones weren't. The USA FSM says that the 722.1 transmission takes the lock, but the 722.3 does not. Perhaps there isn't enough space to fit the lock on the 722.3 transmission.

By the way, it is a Schwingungdämpfer, with a capital, an extra g and an umlaut. Without the umlaut it means a "vibrating steamer". The ä is pronounced as a short e, as in neck.