engine and drivetrain This Cant Be Good... (Mystery Clips - From Timing Chain Master Link!)

[tim385]

Well Ill be ...holy crap Batman...what will they come up with next.KAPOW!!BAM!!....thats the noise the engine makes when the timing chain comes off..

[KFunk]

Well, since I'm kinda in the same boat relying on the same style chain, and I'll be driving my 02 to Wisconsin this weekend, as well as Maine next summer, I'm a bit concerned.

 

I decided to do some googling, since surely we're not alone (Iwis is the brand of chain by the way).  It appears that Mercedes Benz recently switched from using the single oval clip to the 2 little e-clips as well, and a similar distrust was there amongst car guys, followed by reassurances that the e-clips are fine.  Here are a few discussions:

http://forum.w116.org/mechanicals/timing-chain-master-links/

http://www.peachparts.com/shopforum/tech-help/142186-timing-chain-master-link-e-clips.html

 

MB seems to trust them fairly well, even on newer V8s.  The e-clips aren't really holding the chain tension at all, just the pins in place laterally.

 

But of course, what went wrong on gliding_serpent's?  Could it just be the case of someone thinking that the circlips were in the groove, but they were not?  It seemed like an easy mistake that could happen when I was putting mine in place.  If there were that much lateral force going on in the timing chain, I would think that the side of the link itself would've wiggled off by now on his car, but it didn't.

My master link on my car has survived high rpms in around 13 autocross runs so far, and maybe 5K miles, unsure since my odometer recently stopped for a while. 

Edited September 30, 2013 by KFunk

[KFunk]

OK, here's an explanation on the e-clips, for BMW motorcycles:

http://www.bmw2valve.com/motorcycle/1131258.html

 

The original timing chains are endless (no master link) which seems like the safest and best way to make a chain but impossible to install without major disassembly. The job is much easier if the replacement chain has a master link and they are very reliable when installed properly. An alternative to the more common U-Clip type master link however is the double e-clip solution! This uses a hardened e-clip on each link, so in theory, if one clip should somehow fail, the other one will likely remain. In actuality though, it’s nearly impossible for either to fail.

These master links were standard fare on Mercedes Benz V-8s like the 450 and 500 motors for example. On those motors, the duplex chain had 198 links, drove both camshafts up top and wrapped around an idler sprocket below so it was subjected to much more vigorous use. Proven technology!

This is a chain of the highest quality with the best master link available for an easy installation with reliable performance so that you can sleep at night.

 

If you were that concerned, then I believe Pelican Parts has continuous chains.  I really don't want to take my car back apart anytime soon, though. 

[KFunk]

Also, notice that there are 2 different colored master chain links in the motorcycle chain picture.  Presumably, the proper one needs to go in the middle of the chain, and the other one needs to go on the outside.  I don't know why this may matter exactly, but I remember thinking about this a lot when I assembled mine, reasoning through it, and possibly googling it.  I can't recall the conclusion that I reached.

 

I'm not sure how exactly, but perhaps if yours was improperly arranged, it might leave too much gap between the circlip and the link?  It's hard to tell, but I know I played with the possible arrangements of mine and made sure that it was right, when assembling.   

[lilmo]

Chain press works as well, with an experienced hand.

[FB73tii]

Holy Cr*p! I am glad you figured it out. I sure wouldn't trust my engine those tiny e-clips, no matter what Mercedes says. Some bean counter probably found a "savings" of 1 cent per 1000 clips. I'll have to go back through my old timing chains and save those oval clips.

 

--Fred

[gliding_serpent2]

I ordered a continuous chain from blunt. Rad out and chain in is far cheaper than a new engine. Bargain really. I did not install the chain, so who knows if the clips were done correctly... But this is not a risk i have any interest in entertaining.

My current dilemma is how to get the car to the shop (40 min drive)

I wonder if an oval clip would hold?

Edited September 30, 2013 by gliding_serpent

[gliding_serpent2]

As far as why the failure, i wondered if the chain tensioner was the issue. That being said, toby b once said they will not work once you shave .5mm or more off your head. I had only 0.2mm off so likely not an issue.

Would popping the clutch from a bad 3rd to second do it? I had one bad one that resulted in slight locking at the track...

[Preyupy]

Put the clips back in (if they are not a tight fit either find some that are or tighten these up by squeezing them a little bit) an drive it to the shop, keep the revs below 4k and you will be fine. I am sure a new set of clips, properly installed would keep things running fine for thousands of miles but you have had a problem and you will worry about it every time you drive the car. For your own peace of mind put in a non master link chain and have fun with your car.

[lilmo]

I ordered a continuous chain from blunt. Rad out and chain in is far cheaper than a new engine. Bargain really. I did not install the chain, so who knows if the clips were done correctly... But this is not a risk i have any interest in entertaining.

My current dilemma is how to get the car to the shop (40 min drive)

I wonder if an oval clip would hold?

Have the shop pony up for a trailer, unless you provided the chain.  

[KFunk]

I was searching other forums on master link failures, and I can't easily find any other instances of these master links breaking, besides yours. 

 

In the motorcycle drive chain world, there are lots of people that have had the single elongated c-clip pop off.  The small e-clips are actually seen as preferable to them, and more reliable.  While a bike drive chain doesn't see the same RPMs as a timing chain, they are subjected to way more dirt, debris, and stress in all different angles.  Lots more slack, exposed to air/dust, bouncing up and down with the swing-arm, gravity going all different directions as you lean side to side, etc.  

If you think about trying to pop a master link apart with your fingernail, it seems like it would be much easier to pop off the big c-clip.  Those little e-clips are hard to get ahold of and to try and wedge off without getting a tiny screwdriver in there.

On my master link, I didn't see any gap between the circlips and the master link.  It was pretty snug in there.  I suspect something was a bit goofy with yours for some reason.  With as many different engines these are installed in for a lot more miles (MBs, motorcycles, etc.), you'd think someone else would've had a spectacular failure and posted about it (or I'm not googling right). 

Edited September 30, 2013 by KFunk

[lilmo]

tii is closer to current diesel plants than bikes.  Yell at the assembler at the shop, pay them to fix it, and don't go back.

[gliding_serpent2]

tii is closer to current diesel plants than bikes. Yell at the assembler at the shop, pay them to fix it, and don't go back.

The shop sold and closed. That being said... As time passes the more i learn, the more i realize they did a shit job (dont get me into it...)

They also did the oil pump and adjusting that chain. I gave them the info to do it right... But who wants to bet it was done properly?

Lets just say that the front and bottom of this engine are coming off...

Edited October 1, 2013 by gliding_serpent

[Cru Jones]

On most modern bikes the master link is "riveted." What I mean by that is we have special master links that require special chain tool that essentially holds the one side of the link while mushrooming out the pivots. I would think that car timing chains would be put on with the same sort of tool. They make one of those tools for motorcycle cam chains.

 

This is the cam chain rivet tool for motos.

 

[TobyB]

 

impossible to install without major disassembly

Much less so on the 2002...

 

The M10 does things with vibration that I previously thought took an impact driver.

The conditions in that timing case are very different than on a swing arm on the back

of a motorcycle.  And possibly very different than inside a Mercedes chain case.

Might have been bad luck.

Might have been something that the M10 will do regularly.

 

The original master clip seems to stay on, didn't for GS,  I wouldn't use them.

If the cheek plate pops off, then it's going to get ugly....

 

t