Adam's 450 SE Project

[thysonsacclaim]

I've been browsing around the Forum for insight, but I have some questions I couldn't find answers to.


Today we finally pulled off the right cylinder head (LHD passenger side). The head will need to be milled, but it is not very bad. However, we did notice that a number of the water jackets were clogged up. We manually cleaned these and will finish the job chemically to get areas we cannot reach.

However, because of the shape of those jackets, we decided it would be a good idea to remove the driver's side cylinder head as well, clean it and put on a new gasket. Because of this, we decided it will probably be easier to just hoist the whole engine out and put it on a stand for disassembly. This will also make putting it back together much easier as I believe the majority of the work could be done in situ on the engine stand. We will most likely not be doing any bottom end work as it doesn't seem necessary.
The car did run OK before we discovered the leaks. Probably lower on power, but it was mostly fine.
None of the bolts were torqued correctly on the head (all very loose), which is likely what caused the leak, along with the bolt with the broken off head. I did not find any valleys between the cylinders and jackets, which I am so pleased about.

The cam lobes are a little worn, but the valve guides seem to be OK. The valves are only slightly pitted, with one being worse than the others due to water contact. We are going to check the stems and seats tomorrow most likely.

The list of items to buy, which will have to be bought over time due to my student finances is as follows:

2 x Camshaft Sprocket/Gear; Double Row
1 x Cylinder Head Gasket Set; Left
1 x Cylinder Head Gasket Set; Right
1 x Timing Chain Guide/Rail; Clamping Rail/Lever at Tensioner
2 x Timing Chain Guide/Rail; Cylinder Head Inner, Left/Right; 172mm
1 x Timing Chain Guide/Rail; Left Cylinder Head; 143mm
1 x Timing Chain Guide/Rail; Left Lower; 113mm
1 x Timing Chain Guide/Rail; Right Lower Curved Above Crank Gear; 135mm
1 x Timing Chain Tensioner
1 x Timing Chain; Double Row 198 Link with Master Link
1 x Water Pump Gasket; Water Pump to Engine Block
1 x Cylinder Head Bolt; 10x155mm; Allen Head
2 x Woodruff Keys (unknown sizes at this point, may need more than 2??)

I am replacing all guides because I found broken plastic of the type used for the guides. I have no idea which guide, as the top look intact.

Questions are:

1: I don't have any reason to believe the bottom needs work... but how would I know?
2: What caveats should I know about before we begin unbolting the engine mounts & bell housing?
3: Can the engine mount bolts be used for holding the engine on the stand?
4: What else should I look at, that would be necessary (keeping in mind I am a poor student)?
5: Since the camshafts, heads, chain and everything will be removed, how do I ensure the engine is back at TDC for re-assembly? (we made marks on the chain and camshaft, but is there anything else I should know/do?)
6: If the engine is (by chance) slightly off TDC, will this cause serious harm and how would I correct it? Would disassembly be necessary?
7: What do you guys recommend soaking the heads in to clean them up?
8: Am I insane to be doing this, or do you think it is worth the effort?


Thanks. I will be posting pics, but because of DST it is nearly dark now at 5:00PM.



Adam

[WGB]

Good on you for having a go.

1) If the engine made good oil pressure, no knocking noises or oil leaks and no obvious ring blow-by I would leave well alone.
2) Replace the valve guide seals as a matter of course as this is where most oil can get by.
3) The plastic in the engine may be from a  previous guide  breakup - does it match the colour of the present guides. New chain guides are milky white and slowly turn to a dark brown with age.
5) It may be worthwhile removing and cleaning out the sump in case more bits of plastic are blocking teh pump imntake.
6) Time the engine without the cam followers in position and then there is no risk of valve fouling piston.

Keep going and send us some pictures please.

Bill

[thysonsacclaim]

Thanks for the suggestions Bill. Yes, the engine produced no smoke at all (even though there was indeed a head gasket leak), not even on FT. No knocks, only tappet noises because it needed adjustment. The pressure was also always good.

Okay, so that little bit of plastic I found was bothering so I decided to have a closer look at it. It was a small piece, about 6.35cm x 6.35cm x 1.5875mm. A very small bit.

The thought of plastic being in the bottom somewhere was bothering, so I did some rudimentary tests on the plastic shard. I placed it under a scope I have to look at the surface of the plastic. I then cut it in half and submitted it to a test with various solvents I have to see how it reacted. After that, I took the other piece, ground it up, powderized it and did a melting point test on it.

I did the same thing with 2 pieces of the plastic on one of the top guides (I'm replacing them, so it doesn't matter if they're destroyed).

Based on what I found, I do not believe they are the same type of plastic. The surface was different and, more importantly, they melted at different temperatures which indicates they have a different composition. The chain guide melts at a much higher temperature (about 11 C higher, which is a lot) .

I believe that the plastic, while similar in color, is actually from one of the Fuel Injector terminals. On closer inspection, they match the color better (also dark brown from age).

I will still clean out the sump. When I changed the oil, I cleaned out the oil filter canister as it was quite sludgey inside. I assume the sump would be in a similar state.


Questions:

1: What are the cam followers? Are they the rounded metal bits that sit 2 to a cylinder, which are depressed by the cam lobes? Sorry, I am still getting the lingo down  

2: Do you know what the valve guide seals are made of? I haven't taken it apart yet. I am planning a solvent bath for the head, but before I decided which chemical, I need to know if there are any other plastic/rubber bits in there that could be eaten away.

[WGB]

By the cam followers I mean the fingers that the contact the camshaft, pivot at one end on the adjustors/hydraulic lifters (depending on model) and depress the valves.

You will need some sort of compressor to compress the valve spring and remove/replace these arms.

This is my copy of the M117 one that I made.



Once the cam followers are removed it is very easy to rotate any part of the engine - cams or crank without any fouling of parts.

Valve seals seem to be made of different materials depending on original or otherwise. You will however need the little plastic applicator that is provided with the inlet seals as they are slimmer than the exhausts and can be damaged in fitting when passing over the grooves in the valve stem.

Bill

[flutes]

Adam - as someone who lacks the technical skill and knowledge (not to mention equipment) to undertake a project like this I think it's fantastic you're doing this.  The satisfaction of turning the engine over again for the first time will be worth the effort I'm sure.

[thysonsacclaim]

Adam - as someone who lacks the technical skill and knowledge (not to mention equipment) to undertake a project like this I think it's fantastic you're doing this.  The satisfaction of turning the engine over again for the first time will be worth the effort I'm sure.

Funnily enough flutes, I can manage to test the composition of the plastic or clean parts via electrolysis but when it comes to the major mechanical things (how the transmission works, what the kick down does, etc etc) I only have a very infantile understanding.  

The important thing, I guess, is that I can undo bolts and turn a spanner  

I'm not afraid to dive into it, nor am I afraid of mistakes (as long as they don't cost exorbitant amounts of money).

I will most certainly buy a manual before I put everything together, just in case. I do have parts cataloged, if you will. Bolts from the same assembly are in the same mason jars, and the parts are assorted by their relationships to one another.

I see the disassembly as a learning process, which has taken much much MUCH longer than it would take others because I'm doing it for the first time, don't have a manual and don't know the best orders in which to remove things.

When it comes to the reassembly, which will be followed by MS & EDIS conversion, I think I can handle that well. I'm pretty good with electronics.

After that, I will do the long-awaited AC repairs and conversion to propane refrigerant. As it has been 45 F the past few nights here, AC isn't that high on the list anyway.

All in all, it is frustrating, at times literally quite back breaking, but I believe it will be worth it.

The engine will be much more powerful than before (it was a little weak, which is why I investigated), run as if it had 15-20 years of age taken off it and I'll have the satisfaction of knowing I've completed a task that would have cost me thousands of dollars had I paid for it.



I may be lacking in the automotive knowledge, but I like to think most people can do most anything they want to if they put down a good effort, shed some blood and tears and lose a finger or two (haha, okay maybe avoiding accidental phalangeal amputation would be good!).  


I will be posting pictures, most likely tomorrow.



Cheers




By the way Bill, that's some impressive adaptive engineering. Painted and everything. It quite looks like something one could purchase from the store. You care to start your own tool company and stamp copies of that  ? Dr Bill's Specialty Tools? 


Oh yeah, one more thing. I am going to have the injectors cleaned and tested as well. No sense redoing the FI without having them in tiptop shape.

[WGB]

By the way Bill, that's some impressive adaptive engineering. Painted and everything. It quite looks like something one could purchase from the store.

Here's the template to make your own.



All the technical knowledge is in the workshop manual at this site or you can purchase a CD with it all on easily off e-bay.

The Haynes Manual w116 350/450 is very good as is any of the US manual that cover M-B's of this vintage.

The original M117 workshop manual turns up quite regularly on US e-bay as well for about $75+.

Bill

[s class]

I made myself one of those compressors about 2 weeks ago.  Took hours!

You are aware that generally the engine and transmission are removed together as a unit?  Removing the engine only will make it difficult to reinstall without damaging the torque converter neck.

If you must remove the engine only, you must unbolt the torque converter off the engine flywheel, and ensure that it stays behind in the transmission bellhousing, and doesnt try to come out with the engine. 

When reinstalling, place the torque converter correctly in the bellhousing, then offer up the engine to it, ensuring that the torque converter and engine flywheel are in the correct relative rotation before bolting up the bellhousing bolts. 

Oh, and while this is all apart, you MUST replace the radial seal in the front of the gearbox where the torque converter goes in, and the o-ring around the front pump of the transmission.  These are the most common leak areas on these transmissions, and attending to them requires separating the transmission from the engine.   NOt something you want to do again in a hurry. 

[WGB]

I made myself one of those compressors about 2 weeks ago.  Took hours!

But think of all the time and worry you will save yourself by having one - and it works on all of the motors of this vintage.

Bill

[s class]

Yeah, I don't regret having spent half a day on it - I really needed it as I got talked into doing a valve stem seal job on a 500SE W126. 

[thysonsacclaim]

You are aware that generally the engine and transmission are removed together as a unit?  Removing the engine only will make it difficult to reinstall without damaging the torque converter neck.

Nope, didn't know that. I was at the Dr today so I wasn't able to get around to it today. I work the rest of the week, so Sunday / Monday will be the next days I will be back at it.

I will hash the pros / cons of removing the whole thing, just the engine or leaving it in place. Pulling it out will definitely make it easier to work on, though, and that's what I'd like to do.

The whole process is going to take weeks / months, so I'm not really in a hurry.


I've resigned myself to not being able to drive the car until January.


The plus side is with the cooler weather, one can actually breathe outside as opposed to feeling like you're drowning in the humidity. Can get much MUCH more done in this nice weather.   

[jpstuckey]

Adam-

I would inspect the cam followers for any signs of spalling or cracking of the hard chrome plating.  I two 4.5 motors which I have owned that has been the reason for cam lobe wear.  They are fairly inexpensive, especially in comparison to new cams!  I second the recommendation to pull trans with engine and replace front seal and o-ring (you will need a bellhousing gasket, as well).  Motor mounts will probably come apart when weight is taken off of them, too, but they are fairly cheap.

Bill-

Beautifully made tool you have there!  It looks just like the factory tool that I am fortunate to be able to borrow.


John

[TJ 450]

Wow, I can't believe I missed this progress.

Nice work with the head removal.

With the heads removed, how much of a lip is there at the tops of the cylinder bores? Even if there is a slight lip, I wouldn't worry about it. What Bill said earlier is on the money. These engines have a remarkably strong bottom end.

I would remove the engine/trans... It makes the work so much easier and you'll be able to clean out the water jackets properly on a stand.

Tim

[thysonsacclaim]

TJ,

I'm of course out of my league when it comes to automotives but I'll take a gander and assume you're referring to the top surface directly surrounding the cylinder chambers?

If so, the only lip present was carbonization and it was very minimal. One was slightly more than the others and this was the cylinder that was known to have the leak. The surface of the chambers was smooth and shiny. I have coated them in petrolatum to prevent surface rust formation and to keep any water from settling somewhere I wouldn't want it.

I do want to remove the engine, but for some reason the transmission seems out of my comfort zone. I really don't have a clue how they work besides that they spin and engage   

It also seems like a lot more extra work (but will make re-assembly of top components easier and work easier).


jpstuckey,

Thanks for the tip. I will be giving everything a look over. My brother is much better mechanically than I, so he will be assisting in areas I do not know about. I will look at the followers more closely and see what shape they are in.



I really miss driving the car and everyone keeps asking me where it is at work. Despite my err.. lust to drive it, I intend on doing as much work as reasonably possible while it is apart.

I have always wanted an older Mercedes (and some BMWs as well), but have never been able to get a hold of one. Since I have this, as long as I can do things little by little and get the engine more straight, I intend to hold on to it.

[TJ 450]

TJ,

I'm of course out of my league when it comes to automotives but I'll take a gander and assume you're referring to the top surface directly surrounding the cylinder chambers?

That's correct. It sounds like you're all good.

With the trans, just treat it as a "unit" and you'll be right. It is a thousand times easier to simply remove it with the engine in one go. Separating it from the engine in-situ is a bit of a nightmare.

Tim