W126 Benz Oil Spec and Other Questions

[smoo]

I think MB system is a more simplified version of Citroens?
The only way I’ve found after research on diagnosing spheres or accumulators on MB SLS is measure how far the diaphragm is from the thread with a vernier or something that fits in there for reference, like a screw driver. Greater distance means they’ve lost pressure (apparently). I think I have a couple of good spheres somewhere I can check.
Bad spheres will have a bouncy ride, or if no pressure in them at all the ride will be rock hard.
Struts can also go bad an leak internally which can make them sit low in the rear end when parked.

Front bearings are tapered with adjustable pre load. Rear bearings not too sure.
Those engine mounts look buggered, looks like there is a visible split in one?

Failed odometer is common with age. Check out this site. I did my W140 odo gears and cost about $120 inc postage.

https://www.odometergears.com/produc...peedometer/117

Cluster removal tool #140589023300 or use a couple of 90 degree picks but make sure you pull from the correct spot otherwise the pick can grab the cluster screen and crack it.

[GasoLane]

Originally Posted by Citroënbender

It’s also definitely leaning out, hot idle with AC on is over 1200RPM and the economy gauge is pegged to the right side (red). That’s a vacuum leak for sure.

Does that model have an idle control valve?

[Citroënbender]

I believe it’s got an auxiliary air valve, if that’s what you’re referring to.

[GasoLane]

Originally Posted by Citroënbender

I believe it’s got an auxiliary air valve, if that’s what you’re referring to.

Yeah same thing I think. One of the lads in the OzBenz group was having trouble with his W116 4.5L v8 idling fast, tested the valve in a saucepan of hot water and it was seized.

[Citroënbender]

I’ve got them on two Pugs, the rotating cylindrical aperture type, one has stuck twice in 15 years.

Car starts quite readily, cranks healthily, that’s not to say a supplementary air supply isn’t at fault.

The chassis issues have thrown me, I’ll admit. I drove 16km to the workshop to check the driveline out and it handled so awfully my “job focus” is shot.

Waiting on someone at the refurbished Lindfield Village Green right now. It has a surreal, Truman Show feel to the place.

[eb2fairmont]

The tanks on k-jet cars are total seal - no breather. Replace the hose they generally don’t corrode internally as long as the cap is on.

If it’s been sitting check bushes and ball joints they will most likely need replacement. The main thing for good steering is steering box adjustment, and a good steering damper. This is like a mini shock absorber mounted to the main arm and body and filters out most vibration.

Benz recirculating ball isn’t the last thing in road feel either.

[Citroënbender]

Starting to wind down a little, thanks for all the experience shared. Phoned a friend to wiggle the steering wheel while I observed the Pitman arm. Mega slop in the steering box. Compared the rear bounce to an hydraulic Citroën. It rebounded about triple the number of times. This would absolutely be contributing to the vague sense of steering.

The “testing spheres via plunge measurement” is sadly a furphy. Benz only have 23 Bar in theirs, along way down from some Citroën spheres. Pumping hydraulic pressure against their gas reserve while watching a test gauge is the only reliable metric; when the gauge plateaus, it’s service pressure of the remaining nitrogen.

Put a fuse into the central locking circuit after discovering this was blown (no hazards was my clue). Locks cycled endlessly, took it out again! At least I now know the doors lock in this way - saves taking them apart to test each component.

Can’t establish what is missing from the grommet here. I stuffed a bolt in to seal it.

There’s what looks like an old AIR type system on the exhaust manifodl. I’m surmising the missing linkage was a WOT buffering system to avoid over-rich fuel post-combusting. Does this sound about right?

Ye olde splitte hose, as found on many cars. I haven’t yet followed the other end through. A good discovery was the air filter element being near new. I’m assuming these cars came with rubber bungs in the spring turret top holes.



The mighty K-Jet (my phone auto-corrected this to K-Нет!) in all its glorious simplicity.



And my “soft pedal”. This plastic coupling is 2/3 broken away, causing the bulk of throttle freeplay.

And finally, credit to RockAuto. Ordered 10:30PM Thursday, delivered 10AM today. That’s with FedEx “economy” freight, too. Glad I was reminded about them!

[smoo]

That grommet in the air filter housing is where you can adjust the fuel mixture.
You can see it in your second to last pic in front of the fuel distributor.
If you push down on the AFM with the key on you’ll hear the fuel pump run and the injectors working.
The adjustment is suppose to be half a turn out from when it starts to inject, from memory.

MB spheres - I probably read the back yard ‘diagnosis’. Theory is, if there’s no gas left in the sphere, the hydro pressure from the pump or the weight of the car will bottom the diaphragm out in the housing. Makes sense I suppose.

That split hose may off the top of my head run to the idle air control valve which sits behind the dizy, p/s reservoir and under the intake manifold, a real bitch to get at with multiple hoses connecting to it.

What Citroen are you comparing to, out of interest?

[Citroënbender]

A C5, there was one 3m away at the time - not a regular.

I hadn’t thought about the adjustment access - thanks, was looking everywhere for a broken hose or blocked spigot.

Do the sixes and eights share the same motor mounts? I looked at the mounts offered for the W126 380SEL and they seem similar / same.

[eb2fairmont]

Yeah smoo has it there its the mixture adjustment. Dont touch it, its supersensitive.

[Citroënbender]

The aftermarket grille is far better than expected, MB have long discontinued their own item so it was either chase used parts or go new reproduction. Chrome finish is remarkable, it has a decent “heft” to the whole unit.

Was tricked by the horn only working with ignition on! For a while the faults list was getting even longer…

Lower ball joints and those “guide rod” couplings: Are they genuinely more difficult to replace than on other cars, or is it just the amateur owners talking up the effort for lack of comparison?

I think my question on the motor mounts is resolved, W123 and W126 both apparently use the same principal mounts irrespective of engine.

[Citroënbender]

Problem: Vacuum gauge on dash not working.

Solution: Pull dash forwards. Locate un-connected vacuum line and re-connect.

I was hoping this to be the only source of my high (1400RPM) idle but it wasn’t. Will read up on setting lash, as I doubt it’s been done for years.

Sunday I plan to flush oil and coolant.

[smoo]

Before doing valve lash. Ensure there’s no engine leaks from the top end or front of the engine so you don’t have to go in there twice.
M110 common to leak between the head and the cam shaft housing/box.
I did mine with a new gasket. Couldn’t see why it was leaking with straight edge etc. Reassembled and test drive, still leaking.
Had to do it again and this time used 3 bond on the gasket which did the trick.
After pulling it apart the second time one of the timing chain guide pins started weeping oil. Pulled it out and sealed it with loctite thread locker, pity the poor bastard who has to go in there next.

[Citroënbender]

After seeing prices on a stout adjusting tool ($100-up), noting the gasket costs and reading of others having the same leak experiences you describe - I think the job can be re-prioritised. Vacuum leaks, rear suspension and steering slop first. There’s USD$600 with freight sitting in my Pelican cart right now, including a nearside front blinker housing and a bonnet ornament. Everything else is “boring” mechanical catch-up stuff.

This chap has a good walk-through of setting up a steering box, he doesn’t seem full of regurgitated nonsense: http://www.davidpetryk.net/Mercedes/Steering.htm

I think Gumtree and CarSales are telling the tale of where values are pointed for the neglected cars - down to scrap weight only. Similar condition to this seem to be asking $2K unregistered; the question is whether anyone would buy them with rego for $3500. It’s backpacker cash, except for the fuel consumption.

[smoo]

Stout adjusting tool, is that for the valves?
You can get away with the open end on a normal 17mm spanner.

[Citroënbender]

Really? I read stories of them being so tight people bent (spread) their open-enders. These are what I’d seen proposed for the job.

My open-enders are Teng, not Stahlwille, but they seem fairly durable considering what I’ve put them through.

[smoo]

Can’t say I had any issue with tightness.
Depending on the position of the adjuster it can get tight between the cam housing and the body of the spanner but it didn’t prevent me from adjusting them. .
Just went out to the shed and check on the spare engine I have. The adjusters are firm, but definitely not enough to flare the end of the spanner or round the hex…. Maybe those guys get their tools off wish.

[Citroënbender]

That might persuade me…

First misstep. Prior to setting up for a coolant flush, giving the radiator hoses the squeeze test for softness. Top hose, normal. Bottom hose, I feel the unhappy crunch of a corroded anti-collapse spring. Guess the positive is, not finding this after a flush.

[jstanovic]

Smoo is on the money, new gaskets and a 17mm open spanner did the trick for me too.

[Citroënbender]

Thank you. Much more relaxed about having a go, now.

I’m finding no reference to support springs in the lower radiator hose, now wondering if it was just scaly deposits that I crumbled.

Boot locks, is it a design feature that you cannot remove the key with it unlocked? I can remove the key from the lock at vertical and horizontal positions but only when the key is twisted to full travel anti-clockwise can the button be pushed in.

[Citroënbender]

Having some to-and-fro episodes with US vendors.

Pelican: We can’t ship accumulators.
FCP Euro: If you can generate a shipping estimate, it means we can send it.

So I’ve schlepped a lot of my Pelican cart over to FCP Euro. Only the Estonians (Spareto) can supply guide rod ball ends at present, I might put these off for now. Going to be close on a thou; that will nearly wrap the catch-up maintenance for now.

Thinking the boot water is from badly cracking rear screen seal, but will check taillight sealing first.

[smoo]

You could give this site a go.

https://www.autohausaz.com/pn/1233200215

Checked my invoice. I ran the same accumulator in my Euro spec 560 (despite that site saying US models only) and FCP shipped with no issue in 2019.

Boot lock operation sounds normal.

[Citroënbender]

Some grime and neglect is found. I drained the “coolant”.

Then tried to remove the lower radiator hose. I think it was actually internally “glazed” with some variety of Stop Leak type product, and that’s why it felt crunchy when squeezed. This top end of the hose, it’s resisting and grip is negligible. Everything is in the way, and it’s filthy! Note also the cracked AIR supply hose.

To reach the hose, I need to set aside the AC compressor. It has some really impossible fasteners coated in more filth.

All this to properly flush the cooling system.

USD$386 went out on new spheres, front lower ball joints, a steering damper, motor mounts, throttle bushing, fuel filter and the o-ring for that in-tank strainer. FCP Euro were competitive on price for parts and way cheaper on freight than Autohaus.

[Citroënbender]

So I finally got the bottom hose off. Managed to leave the alternator on for now. Note the corrosion and oxidisation to metal fittings, more on that in a moment.

This below is a big deal. The former owner paid a LOT for solving coolant loss problems. You can see the hose was not clamped properly and is damaged. I suspect it was initially replaced due to age and oil softening, but mis-fitted, the car went back for a new short hose, water pump at some point soon after, then a new radiator. But there’s zero mention of a stop leak agent being added to the coolant; I reckon the workshop knew they’d stuffed up and banked on a “Grandpa driven” car never getting stressed enough to pop the hose.

For each hose replacement there was an evac/regas charge for AC service, if the system really was emptied - not just set aside - wouldn’t addressing the shaft seal leak be good practice?

The short hose between water pump plenum and thermostat housing seems OK enough. Relieved as I didn’t fancy the knock-on risks of taking more bits off to replace it.

A long term seal weep on the York compressor, either ignored per my theory above or was this in the “too hard basket” for the specialists because they were worried about warranty on another repair?

[Citroënbender]

I’m still yet to actually change the oil. :-/

Waiting on my replacement lower radiator hose, I discovered that Prestige Auto Parts effectively share an address with Silver Star Spares and Dapco Auto France. PAP have been a bit slow this time, for items apparently in stock my Monday morning order was posted out late Thursday. Still 69 days faster than Sparesbox.

The aluminium spigot eventually cleaned up in situ, I was not keen on removing parts to do it on the bench.

I removed the coolant transfer pipe to remediate its ends - both heavily corroded. After breaking the black oxide crust I pickled the last 30mm of each end in acid solution, then a caustic dip, followed by hot rinse. Tried to flow silver solder into the worst pitting and pinholing, but only achieved a 70% result - out of practice. Another acid/caustic cleanup and then a lick of phosphoric acid followed. Next dry day I’ll be painting the last 50mm of each end with three coats Bill Hirsch Miracle Paint (AKA POR-15). I want the cooling system to be up to a cross-country trip with no special preparation or nursing required.

Once the cooling system flushes clear, I’ll do the oil. For now just amusing myself with degreasing the engine, and light cleaning to the engine bay. Battery tray has seen better days.

[Citroënbender]

Have been trawling Google for images to better understand this motor. Forums have been mixed reading, especially the KE-Jetronic information.

Starting to come to grips with it; the timing chain route is an interesting find, as also the lack of welsh plugs and discovering the bolt-on bellhousing flange. Not looking forward to engine mount replacement, but this is fast approaching as the “innermost” chore - access being best with all the bits so far removed, still off.

Just need to reduce the greasiness a bit more first. I’m slowly identifying the different oils - AC compressor weep, PAS hose failure spray, likely front main seal seepage, hydraulic oil return leaks… I’m yet to accept in my head that engines over 15 years old are likely to need a complete re-sealing and simply resign myself to always doing it as an early-on rejuvenation task.

Interesting also to note the accumulator spheres as received say they’re 155 Bar on the stamping, much more in line with what I’d have expected - some websites showed their pressure as 23 Bar, which sounded quite low. UPS had a red-hot go with my last parcel and the packet of copper sealing washers for the fuel filter has evidently fallen out along the way.

I’m puzzled by the paint deterioration. It’s heavily checked like a true nitrocellulose lacquer. Surely they had moved past these paints by 1982?

[smoo]

I can’t imagine the front seal is a pleasant job in place.
Vibration dampener is keyed to the crank with two dowels. The dowels will need to come out to r and r the seal. Then have to line the dampener up on install.



They have plates down the rhs water jackets of engine. A few of mine were corroded/pitted.
Had 6 or so bolts snap off. Had to drill and heli coil. Would hate to be doing that in place. Pull these at your own risk haha.



I have a pdf manual if you want.

[Citroënbender]

Good picture of the damper, thanks.

Apart from the engine mounts, once I saw the state of “coolant” I figured my first task was probably to inspect and then stress the cooling system. Don’t want to touch those side plates if avoidable. Top marks to the champ who managed to remove the complete injection system with manifold, in situ. Must have had extra long, triple-jointed arms.

Just fitted the replacement throttle linkage bushing and now zero slack in the system. I think nearly every other linkage point needs re-greasing, though.

This weekend laughing at neighbour who’s cooking his Cruze again. 500m trips 2-3 times a day, no EGR cleans and no DPF regens. Wonder why the cooling system keeps failing on him?

[Citroënbender]

Time to see what can be improved in the steering department. I made the M8x1,0 temporary stop pin off a photo from a W116 forum (apparently the item is the same):

Took a photo of the Pitman arm and nut to document alignment, zoomed in and saw the match marks made previously. Going to pull it and set aside in order to set the preload after centering is resolved. 36mm nut there, cracking that with my impact is a power trip. I’ll have the steering unlocked in this process and will counterhold the Pitman arm against the impact to minimise shock to the internals.

[Citroënbender]

Puller vs Pitman arm is currently a stalemate. I’m reluctant to use heat, but that’s probably just cowardice. Have got nearly so much torque on the puller centre bolt as I can apply with the 2’ breaker. Suggestions and mockery welcome.