Removal of the follower (also incorrectly reffered to as a rocker arm) on Mercedes-Benz 5.6 and 4.2 liter M117 / M116 V8 engines is actually quite easy once you purchase the tool.
Shown in the photo above in gold is a brand new valve spring compressor (Not properly adjusted in photos, and this is how they send them). This is a relatively inexpensive too @ about $100. There are less expensive versions of this tool, and also more expensive nicer ones. Depending on how deep you plan on getting into the M116 and M117 engine will dictate weather or not you spend the money for this tool, as there are other ways to compress the springs, along with other ways to remove the followers (removing the cams). I don't want to discourage any DIY'ers from using home brew tools, but I will be honest in saying this tool will allow easy removal of the followers.
Now... To understand this tool better we need to take a close look at the MB M117 and M116 valve train.
In the photo above you can see the valve train assembled outside of the head (complements of me). The tool is designed to depress the coil spring using leverage from the hook, which attaches to the camshaft. When pressing down it allows removal of the follower.
In this exploded view of the valve train (complements of me) you can identify the parts.
Now that you have an understanding of the valve train and it's components, as it pertains to this job; let's have a look at this tool in action and be sure to keep reading for important steps to prevent errors. This job picks up after the removal of the valve covers and spark plugs (not shown).
In this photo you see the proper orientation of the tool. Depending on the model you buy it will be necessary to adjust the tool. It will come to you adjusted in a way that it saves space for shipping and you will have to adjust it to fit as shown above.
Here is a look from another angle. Notice how the hooks wrap around the camshaft, but be sure the hooks do not make contact with the lobes (shiny part).
Here you can see how the tool makes contact with the valve spring retainer.
BEFORE YOU PUSH DOWN!
You must ensure that the piston is at LEAST half way down in it's bore! Do this by sticking a small screwdriver into the spark plug hole. Do not rotate the engine with this tool in the spark plug hole! You can gauge the depth and ensure the valve will not strike the piston when you press down to remove the follower. You must check this on EVERY cylinder! If you do not ensure the piston is down it will result in the locks releasing, allowing the valve to fall into the cylinder! BE SURE THE PISTON IS AT LEAST HALF WAY DOWN. You also have to ensure the cam lobe is not in the "opening" position, otherwise you will have a hard time pulling out the follower.
Check the first cylinder you will work with and every other one by turning the crankshaft clockwise. Put a socket on the big center bolt and an extension to turn the engine by hand. You will be turning the engine each time you check and position the camshaft for follower removal.
Here I am keeping track of the position of each of the followers and their corresponding shim; or button as I like to improperly call them. FOM stand for "Front of motor". These buttons are offered in several different thicknesses and it's best to re-install them in the exact same position and spot as they are removed.
After removing the follower use a high powered magnet to remove the shim. Do not let them fall in the engine during removal or installation. Best to keep a magnet close by. Be sure to keep them in order! Inspect them for wear.
This is what a set of "good" followers should look like. Very little wear, pitting or scratches.
Installation is the opposite of removal.
This concludes my write up for "Removing Followers" on the Mercedes-Benz M117 and M116 engines. Use of this information is at your own risk.
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What is to give light must endure burning -- Viktor Frankl
Another good thread that you've created here with nice pics also ! I can't wait for part-2 with maybe the vave-stem seal replacement. The tool is a great asset and really should be used by anyone attempting this work, as it will more than pay for itself after replacing even one cylinder-banks worth of valve stem seals ! Alternatively, a deticated professional will be more than happy to do the task at reasonable rates and a guarantee to go with it. Those damned magnets have got to be amongst the best tools ever created for a mechanic !!!
Cheers,
Rastus
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"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together". Dwight D.Eisenhower.
Rastus, I'm getting ready to make a new thread that includes valve seal replacement instructions.
I'm also thinking of making a "sticky" index for easy access to specific information. I already have an index on my website http://www.126world.com, but since my website is so dated it don't show up well on anything but internet explorer. That being the case, I'm thinking of making a "sticky" thread index.
What do you think?
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What is to give light must endure burning -- Viktor Frankl
I say go-for-it !!! Everyone wins if you did something like that.
The people at home get to see what they're potentially in-for before they try doing things themselves...And then bringing their mess & problems to you...
You'd also be helping out fellow mechanics who may have jobs in-the-pipe-line but have never seen the insides of these cars before.
It's also good that you expose folks to the necessity of having to use proper M.B. special tools for some, if not most engine-work. So another reason becomes apparent to take the job to people who not only know how to fix these cars, but have these special-tools.
And you yourself may-well grab some business out-of-it-all I'm sure ! The number of visits here has increased dramatically recently, so it seems you're filling a "niche" with good photo's, facts, & information. That's something that BW.org lacks...You only have the blind-leading-the-blind over there...Though it is funny at times, & at least they sometimes try to do the right thing, usually when they take their problems for some-one else to fix when they get themselves in-too-deep LOL...I don't visit them at all BTW, I've only ever followed the links from here. And that's usually been more than enough for me...
Gerry's forum seems ........... Well, I don't visit there either anymore, not since he was banned from here. And even then, it was only to find-out about how his 6-month M104 head-gasket job was going / went...I actually like(d) Gerry, but it seems he'd rather leave you behind than stick-up for you when the going gets tough, & then he'd come over here & drop a tonne of "issues" on this forum. But it was entertaining non-the less. He has a lot of people kissing-his-ass over there...And that's fine, but I think he likes it....
It's a shame RSJ's manners never improved either, but that's the price for learning something LOL ! It is quieter around here without them, but there's also a lot more traffic reading things !!! This is good also, as it means we don't need to type as much LOL !
Cheers,
Rastus
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"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together". Dwight D.Eisenhower.