Mercedes 450SEL 6.9 engine ticking/noise

[daantjie]

I dug up some old pics I took when I was chasing my lifter tick.  These show the difference with a test value, and then also the difference measuring the preload in situ.  The difference is pretty obvious:

[Randys01]

So Daniel ....you have demonstrated the Sir Tools and the later MB variant. They sure give a different reading. This reinforces the likelihood that the Sir Tools version was scribed to the original spec... but whether they were upgraded in later production we will never know.

Your Sir Tools version reflects your lifters are set to orig spec.viz.   .7 to 1.9.  I would wager your shims are in the 4.4 to 5.1 range.
When you put the Series 2 MB ***2300 on the lifter, the read value is of course way out.

What is a fact tho is I have learnt that the 117 589 06 2300 is NLA from MB.

Thus, it seems if you want to buy a new one, you only have the Sir Tools variant and until proven otherwise, they were and are still machined to the old spec.

I have a Sir Tools version [ 5 years old ] and it is original spec .
I think we are coming very much to the end of the road on this topic.

[daantjie]

Randy yes I would tend to agree.
But...
I would still love to see/ have the 100 prefix tool to compare just for shits

[UTn_boy]

Randy, Daantje, what spring are you making mention of?  The hydraulic elements don't have springs in them, and the rocker arms don't have springs holding them on, so I'm rather confused as to what you fellas are referencing.

Aaron see in the schematic below, a bit small, but you can see the small spring inside the ball/check valve, and then the large spring at the bottom:

I'm still in disbelief.  I've taken these apart before to clean them, and none ever had springs in them.....both on the M-100 and M-116/M-117.  Were the spring loaded ones an early/late revision or something?  My M-100 repair book doesn't show these springs or make mention of them either, but they likely would not have since the hydraulic elements are not an item that can be serviced past replacing them. 

[Randys01]

Yes Daniel I agree: I'd luv to get my mawks on a real re M100 variant: but logic says it was scribed to the original spec..7 to 1.9.

The outlook is basically thus:
a sprinkling of orig M100 variants are collecting dust in some disused tool sheds/workshops maybe.
There  would be early M116/7 variants [p/no still to surface]  out there in reasonable nos. [I reckon this superseded the M100  p/no ]
The revised series 2 are probably common-ish.
The Sir Tools version is probably pretty common and largely in the hands of privateers like us.
So long as you know what you've got, set your clearances accordingly.

[rumb]

OK, got my M100 manual out. job 05-213

with newly installed compensating elements rotate engine with starter @30 seconds prior to checking
(pull fuel pump relay)

[Randys01]

Aaron: re valve lifters. Sorry to burst ya bubble mate but my lifters were 78 vintage and they have the springs as indeed do current versions. I have a schematic from the orig 1975 Tech bulletin and it shows...yep..you guessed it...the spring!
When you say you have pulled them apart to clean.........do you mean you removed the little tin cap that seals them...withdrew the working innards and put it all back together and resealed the little tin cap successfully?

[UTn_boy]

Aaron: re valve lifters. Sorry to burst ya bubble mate but my lifters were 78 vintage and they have the springs as indeed do current versions. I have a schematic from the orig 1975 Tech bulletin and it shows...yep..you guessed it...the spring!
When you say you have pulled them apart to clean.........do you mean you removed the little tin cap that seals them...withdrew the working innards and put it all back together and resealed the little tin cap successfully?

Oh, my bubble isn't burst. haha And yes, when I say I cleaned them I mean that I successfully removed the tin caps, pulled out all of the inside parts, cleaned them, (they were all filthy and caked up with sludge) and snapped the tin caps back on afterward.  Unfortunately, this didn't really help anything because the bores were worn to the point of allowing too much oil to escape when the engine was running.  In all cases, whether with a n M-117 or an M-100, there were no springs inside of any of them.  Just to be sure I was't dreaming, last night I went outside to a spare 6.9 engine i have to remove one of the hydraulic elements.  And sure enough, no spring.  At this point all I can do is assume that some were with, and some were without.  Why and when?  I have no earthly idea. 

[Randys01]

To spring or not to spring?........I can understand your disbelief.............now I'm as puzzled.

I am also intrigued as to your success in putting the lifter back together as I found the little tin cap to be a non cooperative  little nark" and felt it could not be trusted to be put back in service. I am further amazed that your lifters were so worn they would not hold hydraulic lock. I found the top of my motor to be about as neglected as could be but the lifters still held pressure. I swapped them out for new as a matter of course.
Love some one else to weigh in on the spring/no spring story. ?

[1960mog]

Hi

There is a other thing that may need to be taken into consideration here.
I have seen many lifters that were jammed due to tightening torque.
Specially used lifters that were removed for a rebuilt or valve job and then reinstalled.
Using the recommended 60 to 65 NM seems to distort the housing and jam the piston.
Often times the problem is solved by loosening the lifter and re tightening them to a lower torque.

[Randys01]

Re torque. I seem to recall this came up once before....there are 2 quoted values in the Tech blurbs over the years. When I replaced all mine, I averaged the 2 values lol!  There's only about 10Nm difference.

[UTn_boy]

To spring or not to spring?........I can understand your disbelief.............now I'm as puzzled.

I am also intrigued as to your success in putting the lifter back together as I found the little tin cap to be a non cooperative  little nark" and felt it could not be trusted to be put back in service. I am further amazed that your lifters were so worn they would not hold hydraulic lock. I found the top of my motor to be about as neglected as could be but the lifters still held pressure. I swapped them out for new as a matter of course.
Love some one else to weigh in on the spring/no spring story. ?

Regarding the tip cap, they'll "snap off and back on with careful determination.  That's not to say that all have come apart successfully, but the majority have.   I knew they were worn simply because I made measurement comparisons with a new one.  The bore was bigger than the new one, and the part that goes down into the bore had decreased in diameter compared to the new one.  At first I thought that maybe the new one was of different dimensions because of an upgrade or something, but the measurements were too close to one another for that to be the case. 

I'm now of the same mind as you are.....why did the ones I take apart not have springs in them, but the ones you tool apart have them?  I just don't know.  I'm as lost as you are.

[TJ 450]

Maybe someone had them apart previously and modified them. You can easily tell them if they have the spring or not by pressing them in (when oil is bled off), if they return to the fully extended position straight away. If there was no spring, they would just remain in the same position.

Tim

[Randys01]

correct Tim...so I cannot see how they can work properly without the spring?

[UTn_boy]

When the oil pressure comes up the hydraulic elements stiffen up and stay raised from engine oil pressure.  The spring wouldn't have anything to do with them falling down while the engine is running.  I imagine the spring was to keep the hydraulic elements up after the engine is turned off to avoid ticking upon start up.  Again, I've no idea why all of the 6.9 and 4.5 engines I have don't have springs in the hydraulic elements, and I have no doubts that what you fellas have seen/found is true.  I certainly get tired of the inconsistencies, though.