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Today's the day I'm finally removing the heads to track down my tick that sounds just like a lifter (but isn't) and the reason for low compression on #6 (probably connected with the tick).
I figured I'd better check with you guys first. I got to the stage where I need to remove the air intake assembly (where the FD sits) and any other stuff that needs to come off before I can get to the intake manifold but then I stopped myself because I wasn't sure what to take off first. I searched for a "how to" on removing the intake manifold and heads from a 380 but I can't find one.

Do I need to remove the air intake assembly before removing the intake manifold or can they both come off a the same time. I know that sounds a little basic to anyone who has already done it but to me it looks pretty much like "you can't get there from here". I don't want to remove things if they don't need to be removed.

I don't need a step by step instruction, just verification that the assembly that holds the FD needs to come off before you can take the intake manifold off? Of course, if you know of an illustrated step by step on the topic that would be even better.

Thanks
 

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According to thsi the whole assembly can be removed together...http://www.oncebitter.com/r107/r107CD1/Program/Engine/107/M116_38/14-450.pdf
 

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Discussion Starter #5
Section 415 of the engine manual has good info.
Yeah... I saw that, but it uses some terminology that I'm unfamiliar with. Like... "Unscrew bearing bracket for guide block control". What the hell is that?
And "Unscrew bearing bracket for longitudinal regulating shaft" Huh?.
And here's one I love..."Unscrew all fastening screws and remove intake manifold toward rear". Could they have provided a more useless set of instruction than that? How about telling me where the bolts are and while your at it... how many bolts get removed?

I spent the afternoon taking stuff off some of which I don't know needed to be taken off.
Plug wires... no brainer.
Rocker covers... no brainer.
Remove distributor. ???
Removed the air tubes.
Removed all the injectors. Did I have too? I dunno.
Removed the cold start injector. ???
Cruise control. ???
WUR. ???
That's as far as I got today. Spent more time thinking than wrenching. Took many pictures.
Tomorrow I'll start removing all those 5mm (maybe 6mm?) Allen bolts that I'm assuming hold down the intake manifold. Maybe 9 on a side?
 

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Discussion Starter #7
End of morning 2 and I'm making progress but it's slow going. There is just too much to try to remember so I'm marking everything with my Label maker.
I think I identified all the 6mm Allen head bolts that need to be removed but I just don't know for sure.
In the photo below the red arrows point to all the 6mm Allen bolts I removed on the right side...there are 8 of them. The left side looks pretty much the same relative to bolt pattern.
Is that all of them or are there more?
2605528
 

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Here are some PDF's that I created a few years ago from various web sites that have now disappeared.

You will be interested to read in the first paragraph of the first pdf, "About 1,000 miles ago, I also started getting a pretty bad ticking from the passenger-side
valve-train ... indicative of probably a bad hydraulic compensating element ("lifter") or less likely, a bad rocker arm
".
 

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You will be interested to read in the first paragraph of the first pdf, "About 1,000 miles ago, I also started getting a pretty bad ticking from the passenger-side
valve-train ... indicative of probably a bad hydraulic compensating element ("lifter") or less likely, a bad rocker arm
".
[/QUOTE]

Interestingly, later on he finds a bad exhaust manifold gasket that attributed to the ticking.....
 

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Discussion Starter #12
Finally got the intake manifold off. What a PITA!
They have more crap connected to that intake manifold than Carter has Little Liver Pills (talk about an old expression :)).
Here's the intake manifold sitting on my garage floor.
2605828


And here's a photo of the very dirty valley.
2605829
 

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Finally got the intake manifold off. What a PITA!
They have more crap connected to that intake manifold than Carter has Little Liver Pills (talk about an old expression :)).
Here's the intake manifold sitting on my garage floor.
View attachment 2605828

And here's a photo of the very dirty valley.
View attachment 2605829
Jyuma, I admire your courage in doing this job. Your engine, garage-floor are so clean! Nice! As I am not much on engines, I was wondering what you are fixing by removing the heads. Also, will you be using helicoils or timeserts or nothing when you reinstall?
Good luck with the project,
 

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Discussion Starter #14
Jyuma, I admire your courage in doing this job. Your engine, garage-floor are so clean! Nice! As I am not much on engines, I was wondering what you are fixing by removing the heads. Also, will you be using helicoils or timeserts or nothing when you reinstall?
Good luck with the project,
#6 Cylinder has low compression... not terrible compression, but a good 30 psi lower than the other 7. Also, there is a loud valve or rocker tick that I have never been able to silence.
And of course there's the fact that all the rubber and plastic parts that you can't get to, especially the ones that appear to have grown like moss on a vinyl fence between the intake manifold and the air metering assembly, are 36 years old.

I gotta say... the hodgepodge of parts, tubes, hoses and brackets that Mercedes has hanging on and around the intake manifold and air metering unit, gives one the distinct impression of an afterthought... an engineering Mulligan.

I don't plan on using Helicoils or Timeserts but I'll cross that bridge when I get to it. So far I've been mildly impressed with how easy all the nuts and bolts were to remove. Mercedes must have used high quality hardware or surprisingly effective anti seize compound because even the dreaded Allen head bolts broke loose with little effort.

I've taken dozens of pictures and even marked where things go with labels from my label making machine. There's little doubt that I'll be able to get everything back together, but whether or not it makes any difference in performance rather than mere appearance remains to be seen.

The dark and sinister looking area between the air metering assembly and the intake manifold has always been a bit of a mystery to me... but not anymore. The only remaining mystery is "how crazy am I going to get with cleaning and re-plating before I put this mess back together"? :)
 

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Working on the top of the 116/117 engine is a whole different level of work as compared to an older Chevrolet or Ford V8. Change all the rubber parts while it is apart, including the large boot under the fuel metering unit as well as all the donut / 0-rings between the halves of the intake manifold and any other rubber you find. I also suggest that changing the electric switch at the throttle plate is a good idea. It does requires a carefull adjustment to get it to operate properly. Do not adjust the idle stop iteself. It is important that the intake manifold halves seat together properly and this can be examined carefully before installing the manifold. Many have not gotten the large rubber donuts between the intake manifold halves properly seated and this causes a whole lot of extra work. Get it right the first time. I have used a very light wiping of silicone grease on those donuts which seems to help them slide into place where they belong rather than getting pinched.

Any bolt, especially the allen head ones, which show any deformation, replace them!

Often, you can be successful in not doing thread inserts into the block. Yes, thread inserts are a pain and take several hours. ONLY use engine oil to lubricate threads and check to be sure the threads are clean and clear. You might want to run a thread chaser into them as needed.

When you torque the head nuts, if they go up to proper torque evenly, you will "probably" be ok. The moment you get that sinking feeling where the further you tighten a bolt, the looser the bolt feels, then you must take it all apart and do the inserts. I hope not.
 

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Discussion Starter #16
All the parts... nuts, bolts, washers, tubes, hoses, sensors, switches, housings and brackets have been cataloged, marked and stored on shelves awaiting cleaning. It appears that I cannot escape the excessive cleaning gene I was not born with but rather developed with the onslaught of advanced age.

Intake and air flow metering stuff.
MercIntakeReadyForCleaning1.jpg

Components, brackets and air tubes.
MercIntakeReadyForCleaning2.jpg

Fuel lines and cables.
MercIntakeReadyForCleaning3.jpg


And the fact that I creating an entire plating area in my shop isn't helping me back away from my obsession.
MercPlatingStation.jpg
 

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Been there done that. Make sure you also get the updated metal flange. It is a required part now.

I got away without updating the TPS sensor. It was replaced not that many miles ago. Motovof my generation YOLO :p
 
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