*** For those interested in doing this, just watch the updated long version in post #14 - very thorough ***

Numb from research, I'm almost confident enough to DIY the headbolts on my '10 c63 w/96K. Putting together a list of everything I should address while I'm at it and came across the following video that talks about flipping a pin in the camshaft adjusters primarily to address a tapping noise at start-up(which I don't have) but a given(for this mechanic) at 150km - ff to 3:00...

You Tube

Seems pretty straight forward and 'appears' separate from locking the backlash (opposite side) but unsure? Searched, but can only find it mentioned in this guys video (has several on the m156). Anyone here do this and can comment?

 

I'm also interested in any feedback for this trick...

 

well it Tasos say it then it may as well be gospel truth as far as im concerned....i WISH i had known about that pin before I did my headbolts a year ago. When i saw this vid a while back i did the whole face-palm and have been contemplating opening mine back up JUST to flip or replace that pin.

 

Yeah - he's videos have given me enough confidence to try and best I can tell, the backlash is only secured to the gear(s) and not the internals that are removed? I hope to pull the valve covers end this week (both leaking), and am 99% certain will have to replace HBs - if so, will order parts accordingly(still unsure about lifters until I inspect), and will attempt this 'flip'. If by some wild chance, someone before me has already replaced the HBs(one can dream ), I may chicken out of 'flipping' - will know when I get there and report what I find/do.

 

gmore, have you gotten around to trying this yet?

 

No not yet. Been nursing a re-occurring neck injury but soon I hope.
I had never noticed the cold start-up chatter from the driver seat but my brother pointed out to me so I'll have a point reference when I do (video below) with hopefully a successful b4/after. Will post when I do.

 

 

spring guide stuck to plate


remove with magnetic tool
Finally able to get to HBs and flip the pins(DS only thus far). I expected to move at a snails pace but a 'comedic' series of events has had me moving even slower(eg: elusive 40TDC at crank w and w/o plugs with a later discovered warped rear cam straight edge/lock tool adding insult to injury). Anywho, other than the 5 T30 adjuster plate bolts(which have been by far the tightest ones to remove up until this point), flipping the pin(at least the method I chose) is arguably the easiest thing I've done thus far.
The most prudent thing to do is to probably dissasemble everything, clean, lube, flip pin and reassemble (as shown partially in the video and 'probably' not all that difficult). Given my luck(aka, lack of skills) I chose to...

1: Remove 5-bolts and top plate (note: spring guide was stuck to plate on both I&G - see pic)
2: Remove spring
3: Remove pin with a flat tip screwdriver with magnet attached (see pic)
4: Flip pin and reinstall
5: Re-assemble in reverse order

Tips...
* Given that WIS, Tasos, and all DIYs recommend inserting a bolt(or timing tool gear lock) on the adjuster prior to removal it's obviously an important step, but the bolt is more of a plug(not threaded at least not on mine) and an M5-8 is pretty loose(can easily use a M5-10 and maybe longer again... on mine) and my timing tool at a tad over 5mm thick wouldn't completely fit thru to the 2nd gear - be very careful with this step (could easily drop into 'chain cavity') - in addition to blocking off that cavilty with lint-free towels(as best I can) cleaned that area and taped the screw in place. Once the adjusters are off, wasn't difficult to replace with a longer screw in place(no gear tension) and assume is very important on the re-install.
* the 5 plate bolts are pretty difficult to remove (at least holding the adjuster by hand) - I sprayed a cloth with brake cleaner and cleaned/dryed bolt heads with a torx bit to get a better grip. I haven't checked WIS yet but doubt there's a torque spec for re-install but will post if I find
* If by some chance you get the pin sides confused, the 'new' side(one that gos face down) has a tiny circle in the center - I assume worn by the spring.

Will be a while before I can do an 'after' (still need to order HB parts and again, moving slow) but am considering replacing lifters as well (may post another link for advice on this) which would somewhat negate any b4/after. With that said, Tasos states 99% chance the start up chatter is this issue and if you're skilled enough to remove the adjuster, this pin flip is a no-brainer.

If I get thru this HB replacement (and the car starts) may post a 'noob tip addendum' for the less experienced/mechanically-challenged - again, it may be a while

 

spring guide stuck to plate
Sorry - pic of spring guide on plate...

 

Thanks for posting your updates. I just watched your video. Wow, that sounds like a pretty strong rattle. Mine doesn't sound as loud but maybe it's also the angle from where it was recorded.


Which lock tool did you use that was warped? I'm trying to figure out if I should go with OEM timing tools or aftermarket. Thanks!

 

Bought mine used from a reputable ebay dealer a while back (black case Chinese one you can find on Amazon) - I'm guessing it was fine new but maybe bent when the previous owner torqued the cam bolts? I pressed it out and can probably get by with it but am ordering a new 'red case' one on ebay just to be safe - I think quite a few people have had good luck with them but imagine questionable after a few uses? Needless to say, I wouldn't order another used one unless it was an oem-grade model and would probably recommend that if it's going to get multiple uses.

 

I attempted to tackle this today but ran into a problem. The pin looked good, I flipped it anyway, but the adjuster side is worn and I'm not sure its supposed to look like that.

gmore did you happen to get any pics of the plate side?

What do you all think?

 

 

I wonder if a stronger spring needs to be placed into the hole pushing the pin. Doesn't it seem as though the pin is somehow lifting up a bit and therefore wearing the top of the metal plate?

Edit: Tasos just posted another video

 

Thanks, just saw his video. He replied to mine as well. He's such a great resource. It looks like the plate wears over time along with the pin. The wear on mine just seemed strange, because it wasn't a smooth ramp, mine seemed notched so that it catches before it actually locks out at the bottom. I'll put it back together, check the other adjusters, then see how it goes.

 

I posted this video on youtube(as well as started another thread that I'll ask to remove) that was after I had flipped the pin...
https://www.youtube.com/watch?v=brMQ...ature=youtu.be

I now know it was pausing/clacking beforehand (from the sounds) I just never caught a visual to see what was happening. Tasos responded to the video that he felt it was the camshaft adjuster and to try flipping the pin, which I had already done but opened back up to be certain it was right...it was. To experiment(since I'm pretty certain it's toast) I went ahead and re-inpspected(will post some pics below) stretched the spring a bit and rotated the top 1/5th turn(flat plate where bolt heads contact) to avoid the wear the the spring guide created (visible and mildly felt but spaced taking a pic of that - will try to do when I remove/replace) to improve down-pressure on the pin, and re-installed the gear. The 1st couple of cranks resulted in fewer/milder 'clacks' but fully returned by the 3rd turn. Took a chance on ebay with an offer on a used one yesterday that was accepted late last night/paid-for and then was cancelled this morning due to OOS Oh well.

Your chatter doesn't seem near as bad as mine and if you don't recall any clacks getting to 40-degrees to remove - maybe the pin flip will fix? The issue seems(for me) to be mainly at start up (which I assume is the purpose of the pin/spring?) and at 95K my lifters looked pretty good with minimal noise but the worst ones were on this cam - have replaced all.
Haven't had a chance to watch Tasos new video in full (but obviously will) but in his engine rebuild #7 or 8 video, he lubes the gears internals and then cranks the 5 bolts as hard as he can(no torque specs here) - I did best I can w/o issue (hard to get much leverage) but may add a bit more with them mounted - my decision still out on that. Am rambling at this point - not sure how much they'll help but will post some pics below for comparison.

 

may be a while, but will post spring guide wear as well.

 

lifter wear

 

Finally had a chance to watch the whole thing...Great Video! Wish I had it a week ago
Will reference in the 1st post

 

Yeah it is, it was very helpful. I think he posted it in reply to my video since I was asking for clarification on how much plate wear is acceptable. Very cool of him to do so.

In regards to the free play I saw in my adjuster, I found this video linked in another thread on mbworld. Looks like the amount of play is within spec? I don't remember if all 4 of mine had this much play though. I've also never taken apart or played with a brand new adjuster.

At 6:39

 

Yeah - he replied to me with a link to 'play' in the adjuster while mounted but mine didn't have any. It's possible there is play in a different position (when mine was pausing) but figure is moot now. Given that mine was strictly at start-up (really no issues beyond) I'd a been tempted to leave alone but now that it's open and I've installed new lifters will address one way or another. Have been keeping this build VERY budget (still not certain if the cars a keeper...long story) but may have to finally bite the bullet on a new one. Fortunately not my daily driver so can take my time.
LMK how yours turns out.

 

With the current level of information on the pin and plate wear, what are the experts thinking is the weak link? Pin or plate? It looks from the images that the plate is softer and the hardened pins are causing the wear. BUT, iss this metallurgical or is this fatigue related?

Does anyone know the materials and finishes of either? I'm guessing WIS doesn't show this level of detail. Has anyone that has access (long shot) to an XRF scanner verified materials? The plate is relatively simple to manufacture pending material and finishing/plating. A stronger material could alleviate/eliminate rather than just replacement with OEM.

From the sound in the videos, plate rings like steel, and being in a sealed oiled bath would assume ferrous. Pins I assume are hardened alloy and not stainless (316/416). Wonder if something like electroless nickel plated steel would be strong enough to resist the levels of wear being seen, or going to something like a duplex or inconel would be necessary, or just overkill.

 

If you're thinking about tooling to make a plate(the one with the pin cavity), Tasos in the video references in the video someone that was planning on it but don't think that ever came to be(at least that I could find). Can't imagine it worth it - most with M156 will likely replace the entire adjuster. There is no WIS for the pin - strictly educated guesswork to postpone the expense of an adjuster.

 

wow...thanks for posting that video...it would seem that it inherently due to design will wear the edge as the video will show over time. great info. mileage for the video showing the wear, 2013 with ~41,000mi (66,000 km)

 

You're probably right, the market share is pretty small. Tooling certainly wouldn't be the issue as I type this from my machine shop, but the development cost for engineering, material selection, fatigue analysis, and the potential liability would likely never even break even from a cost perspective, they market just cant bear it. Seems like a relatively easy to machine part, but other factors keep this one on the "shelf."

If someone decides they want to have a go at it, let me know and Ill cut some samples and send them out for testing.