Zel's Motoring Adventures...Volvo, Renault, Rover, Trabant, Invacar & A Sinclair C5 - Updated 13/11.

[Zelandeth]

The deposits look silvery in person, it's a bit hard to tell in the photo.  I had to futz about with lighting quite a bit to get them to show up on camera.

Currently raining so out of curiosity I decided to take a look at the camshaft setup on the spare head.  This was as much for my education as anything.

As I expected there is a pressurised oil feed to the bearings the camshaft sits on.  Sadly also as I expected it doesn't sit on removable bearing shells, but they are part of the head itself - so they're likely machined as a pair.  So I probably couldn't take this camshaft and put it on my existing engine, unless anyone knows different.

I'd otherwise have been curious to see if this made any difference...as swapping it *looks* like a pretty simple process, assuming I can just capture and lock the timing chain sprocket - the camshaft is keyed so it can only go on in one spot, so provided I don't let it move that shouldn't be a problem.  In theory.  I confess to having very little experience really working on OHC engines.

Here's what I found.

Cylinders are numbered from 1 at the crank pulley end to 4 at the flywheel end.

Corresponding rocker/cam carrier assemblies in the same order.

Then the camshaft itself.

My summary: It's not from a new engine but would be absolutely fine for years yet.  The actual lobes and followers all look absolutely fine.  A little dirty from sitting around for goodness only knows how long, but a world away from the one in the car.

Two main next steps I will be taking - once the incoming weather system has moved on anyway.

[] Pull the rocker cover again and inspect anything.  If the cam follower on the bad cylinders are being eaten away it should be pretty apparent I'd think as the clearances will have opened up.

I do wonder if it's me having set those which has tipped the scales, as a couple were well wide.

[] Drop the sump and pull a few caps off to inspect them and the crankshaft.

That should give us a picture of where we stand with regards to the condition of the engine as a whole.

Then we can see whether we're looking at wholesale replacement or potentially a head swap.

 

[Zelandeth]

In sharp contrast to the Mercedes I'm glad to report that the oil drained from TPA was completely devoid of sparkly particulates.

The particles there are just general road detritus knocked off the fins on the sump and underneath of the silencer when removing the sump plug.  No visible fuzz on the magnetic pickup either which is always reassuring to see between services given this engine does get worked quite hard.

Still definitely weeping a bit from somewhere in the vicinity of the crank seal or distributor but as it doesn't seem to be getting worse I'm leaving it be for now.

[colino]

The cam wear looks like it has been unused for years and then recommissioned.  I think the regular oil and filter changes are the only sane way ahead as you already know the engine is worn and anything going in new to pair with worn surfaces will mirror that wear pdq.  Don't recall oil pressure at 1 bar being exceptional for these engines when older and hot.

I'd enjoy it as is and save up for a rebuild/replacement.  (And hope it soldiers on!)

Edited September 10, 2021 by colino
fat fingers typing

[Zelandeth]

2 hours ago, colino said:

The cam wear looks like it has been unused for years and then recommissioned.  I think the regular oil and filter changes are the only sane way ahead as you already know the engine is worn and anything going in new to pair with worn surfaces will mirror that wear pdq.  Don't recall oil pressure at 1 bar being exceptional for these engines when older and hot.

I'd enjoy it as is and save up for a rebuild/replacement.  (And hope it soldiers on!)

If it were just a bit low on the idle pressure I'd be content to leave it be and just treat it gently, but it's the fact that the pressure has decayed over a relatively short period of time that is worrying, though it still pings straight up off the top of the gauge above about 1700rpm.

Milton Keynes is a downright aggressively unfriendly place to have a breakdown, so sorting it before rather than after something goes bang is definitely the plan.

 

Just realised I made mention of the magnetic oil particle trap on the Invacar but have never shown it.  It's the little black cylinder just below centre frame in the oil filter housing.

You can see the head immediately below where it unscrews.  Smart bit of design.

New filter now in place...had to hold off that last step yesterday as I'd misplaced the new filter I bought a while back.

For those who it's useful for, the Bosch filter equivalent to the usually quoted Mann W712  is a P2056.

 

[LightBulbFun]

1 hour ago, Zelandeth said:

For those who it's useful for, the Bosch filter equivalent to the usually quoted Mann W713  is a P2056.

 

forgive me as I know this is a little pedantic but given that fitting the wrong oil filter could ruin someones engine I figured id best mention

but the part number Mann oil filter for the later Model 70's who's engines have a spin on filter is W712  

(and if you have an earlier Model 70's who's engine has a cartridge style oil filter then its Mann H601)

 

[Zelandeth]

I officially have no idea why my phone is determined to autocorrect W712 to 713...but after retyping it three times I've now corrected that.

[Zelandeth]

Car shuffling has been undertaken to get the Merc into the most sensible location for open heart surgery. 

Aka: The spot that's both near to the garage and doesn't block anything in when I immobilise it by removing major parts of the engine.

The BX much to my shame hasn't been touched in months.  Though I did poke around at the carb today a bit to get it to idle properly.  Needed the choke on slightly before.  Think the plugs are a bit fouled up too as she idled a lot better after I have her a couple of good revs which blew a huge amount of sooty crap out the exhaust.  Think a good run will make the world of difference.

Think picking up the brake pipes for that really ought to be a job for this week too as it's far too long since I did anything with that car and she deserves better.

I keep forgetting between the times I get into that car, despite how shabby it currently looks inside just how incredibly comfortable it is.  I really do want to get a chance to properly drive it!

Depending on what I find when I start pulling bearing caps off the Merc it may well be done before that gets sorted unless I find a cheaper source of replacement bits than I've managed so far.

Nothing more in depth happening today though (may drain the oil from the Merc, but that's about it) as I'm still awaiting the return of several tools lent to a friend last week...which I was promised would be back this morning.  Yeah... apparently not.

[Zelandeth]

Had a bit of a bumble around this afternoon... lacking half my usual tools so not much useful I can do.

Made a point of checking that with both the air lines hooked together that I can reach everything, and yes I can.

Useful to know.

I checked over TPA to make sure there were no oil leaks following the filter change yesterday...there weren't.  However I spotted something that I had completely forgotten about.

This is what the inside of the rear of the rear wheel tubs should look like.

However this is what the nearside one looks like.

The rear foot or so is missing from when the car obviously took a knock on this corner somewhere in the past.

Not ideal.  This is also why the body in that area wobbles.  More importantly though it means that the ignition coil will be getting absolutely soaked any time I drive on an even vaguely damp road.

My solution comes in the form of a random bit of aluminium I've had floating around in the "this might be useful one day" pile for ages.

This will go roughly here.

Looking from underneath...

It will be both bolted to the chassis, riveted to the body and glassed in place and I'll cap off the remaining hole from above too.

This will tie the wheel tub, side body moulding, rear body moulding and the chassis leg together.  Hopefully get rid of a bit of the rattling from that area.

Last job for the day was dealing with this mess...

This absolutely had nothing to do with some idiot reversing 2.8 tonnes of camper van over it a few months ago.   Nope... definitely not.

Ten minutes later, nobody would ever know anything had happened.

Well...except for me just having admitted my idiocy.

I gave the BX a good hour or so of running - during which quite an amount of rusty gunk was blown out the exhaust.

I'd cranked the idle speed right up to 1700rpm or so to help get some heat into everything and some charge back into the battery, did several rounds of exercise of the suspension too.  Cooling fan cycles in and out perfectly as it should and doesn't seem to have any issues even with a massively over fast idle.  Yes I did back it off again so I didn't confuse the heck out of myself next time I start it!

If my tools resurface tomorrow we'll see about starting to get dug into the Merc.  If not... I'll find something to do.  Have decided that I'm definitely getting the brake lines ordered/bought for the BX this week.  It's sat waiting it's turn for far too long.

[Zelandeth]

Zip to report today as my tools still haven't reappeared.  If we get to lunch time tomorrow I'm going to be knocking on the door of our friend who's got them.  I was promised they'd be back at the start of last week, then Saturday and Sunday morning.

When I do have my kit back on hand I'm going to make a start on investigative surgery on the Merc.

My *intention* is to video most of this process as I figure it's actually pretty good real world mechanical investigation that might be interesting.  About time I did a fleet update video anyway... though that will be separate as I suspect it'll wind up being quite a long one anyway.  Long enough I'll need to actually do some editing...

Don't expect anything fancy.  Will be video and audio just from my phone so we'll not be going for any production quality awards.  Depending how it comes out might never see the light of day.

 

[Zelandeth]

Progress of a beige sort.

Made a run over to Chevronics today and they had everything I was looking for on the shelf.

That's both rear axle brake lines and a steering rack gaiter set.

Only one gaiter is actually split and likewise only one of the brake lines has burst...but my thinking is that most likely the two "good" ones are likely to be in a similar condition to the failed ones so just made sense to grab the lot.

No excuse now really for not getting on with getting it sorted out.

Well, getting it to a state where I can take it for an MOT anyway.  Sure I'll come away from that with a laundry list of things needing sorting but given the car has been off the road for so long it's a step in the right direction.

Wouldn't surprise me if a lot of the hydraulic lines at the rear need changing, but I'd rather have had a proper look at it on the ramp in the garage before writing a shopping list for that.  If a lot need changing it will probably be time to drop the whole rear subframe in the interests of access.

Let's see what happens once I've had a chance to get these fitted though.

[Zelandeth]

Figured I'd keep up the momentum on the BX progress.  Didn't have much time today so decided to concentrate on a bit more diagnosis on a minor but important item that's currently non functional - and judging from the MOT history has been that way for a while: The speedometer.

Of course being the exceptionally cool rotating drum affair this is doubly important as there's no point in having something that interesting that doesn't work!

Pulling the instrument panel out is a fairly painless task and only takes about five minutes once you've learned where the fasteners are and that 3 out of the 5 steps in the Haynes manual are totally unnecessary.

Spinning the input to the speedometer with an external source (Allen key) revealed the speedometer responded, if a little sluggish to return to zero.  After twiddling the thing for a couple of minutes I'd got the trip meter to move visibly as well.  This is good as I'm sure I've read that the drive to that can fail.

This meant I needed to delve deeper.  I had hoped that maybe I just hadn't seated the cable right (it's a right pig to get on as there's next to no slack in the cable).  Unfortunately driving the car back and forth without the instrument panel in place showed no movement from the cable.  Not what I'd hoped for...that means either the cable is broken, detached at the gearbox end or the drive in the gearbox is stuffed.

Of course being a suitcase engine the gearbox is in the sump...and mostly totally invisible from above.  This is the grand total of how much of the cable I can see.

I note it does appear to be a two part cable...I kinda wish I'd known that before the swearing involved in getting the instrument panel out the first time.  Next job will be finding out if the break is in the upper or lower portion.of the cable...if the upper that should be a pretty easy fix.

If it's the lower section that's going on the "sort once it's a working car again" list.  At least it's no huge hardship these days with a plethora of smartphone apps available to provide a GPS based speedometer.  That'll do just fine to/from the MOT station.

 

EDIT:

The instrument cluster is coming out again tomorrow.  The light behind the speedometer has gone out again. 

The panel needs a good clean anyway as there's a lot of gunk on the inside of the plastic lenses and I'd like to make sure that the worm drive for the odometer/trip meter is properly greased up.  This will give me an opportunity to try to repair the damage to the flex PCB and see if I can track down where the permanent 12V feed to the clock is disappearing (it currently resets to 0:00 every time you turn the ignition off).

I have a good quantity of warm white wide angle LEDs on hand so will do a bit of experimentation with those for the illumination.  I'm not messing about with the warning lights, but given the dash illumination is on whenever the ignition is on the BX *and* I know this dash has a plethora of scratchy connection issues, if I can eliminate the heat, power consumption and maintenance aspect there it would be a bonus.  Don't worry, if it looks crap I won't do it and will just try to get the normal lamps to behave reliably.  Just one of those things which while I've got it in bits anyway seems worth investigating.

[Zelandeth]

This evening's entertainment. 

I had hoped this would be a pretty quick strip down, clean and reassemble.

Strip down is pretty easy.

Definitely needed a clean!

Sadly my hopes this would be a really quick job didn't last long.  Apparently at some point in the district past someone has tried to fix the dead speedometer...by unloading about half a can of WD40 into the instrument panel.

Everything is slimy and sticky.  While unpleasant this isn't generally a huge issue as I just need to clean it.  Here's the issue though...The oil has got in between the plastic window in front of the banks of warning lights and the plastic window in front of them.

In itself this is unpleasant to clean up...but the big issue is that it has eaten away the printing on the filter gels.  This is what I found when I peeled them apart.

 

Quite how badly this has eaten away at things is clear when you hold them up to the light.

 

Realistically I'll need to either remake these or find replacements.  I'll make sure to get a high resolution scan to allow me to make a replacement digitally and print out on transparency film.  I don't have time for that right now, so this will be a project for somewhere down the road.

For now I've done a bit of patching with a marker.

Not great but better...at least the dash illumination won't shine through the left hand one like it used to.

The single biggest cleaning task I was worried about though was the bit of plastic which has that diagram of the car printed on it.  The plastic is edge lit and provides a light pipe effect to make the diagram glow.  If that came off I'd be stuffed really, I don't have the resources to remake that.

Thankfully this was the result of ten minutes of VERY careful cleaning with a microfibre cloth.

Jumping ahead a bit, here's how this area now looks when lit up.

Far less blotchy light coming through from behind and it's way brighter now as the plastic is clean.  The bezel isn't fitted there so there's a lot of spill from the sides.

The warning panel on the right always looked blotchy before because the filter gel was actually stuck to the plastic lens.

Now...

Quite a lot of warning lights that just aren't used on this car being the base model. 

[] Brake pad wear indicator (no bulb fitted or evidence of it having ever had one).

[] Glow plugs... obviously, it's a petrol engine.

[] Clutch temperature warning for the semi-auto gearbox - it's a manual.

[] Exhaust temp - only applies to cat equipped cars.

[] Oil level warning - very sadly not fitted.  That may get upgraded as it's a feature I think is really sensible to have.

In addition to these though, this one isn't even in the handbook.

So I assume was there intended to show when the engine was cold (note that the BX never had a temperature gauge fitted), but never actually got used.  Would be quite a nice thing to reinstate.

Equally there two red lights alongside the "Econoscope" (a two-light based vacuum meter basically) in the middle of the dash.

These aren't mentioned in the handbook either.

Over on the other side we're also missing the indicators for the doors being open...these would be LEDs in these four locations.

I'm quite surprised that they actually went to the extent of omitting the LEDs... I'm kinda curious to know if they were fitted if the indicators would work.  Only in the front obviously...there aren't door switches on the rear doors...or bonnet, or boot...so those lights *definitely* won't work.

The pointer for the speedometer needs a good scrub up and coat of paint...it should be white, not lumpy and rust coloured.

I'm still having big issues with scratchy contacts basically everywhere on this panel, so we may end up going with a more wholesale LED retrofit as I can just solder them in.

The panel has obviously issues...there are a bunch of broken clips, the above moth eaten light gels, and several "interesting" prior repairs to the flex PCB.  Oh, yeah and I need to fix this.

Which I'll need to find a pin out for so I can figure out what's meant to have voltage or ground on it.  The clock does work...insofar as it turns on with the ignition and then keeps time.  However it resets to 0:00 as soon as the ignition is turned off.  It also doesn't dim when the headlights are turned on as I think it should.

The flex PCB on this is one of the most difficult to follow I've ever worked on, so really hoping I can find a proper schematic which shows the pin connections so I can just buzz them out with the meter rather than having to trace every one out... That's for tomorrow though.  Oh, and trying to remember where the bottle of sewing machine oil is so I can put a tiny dab on the speedometer bearing to hopefully thin out the WD40 goop currently in there.  Little smear of grease will go on the work drive for the trip/odometer too...which was one of the main reasons for pulling it to bits.

This has turned into a bit of a ramble, sorry!

[PhilA]

Good luck with the dash- I remember the similar fun I had with the Renault.

Re: Invacar belt noise- with ribbed/bladed belts if they sit at a slight angle like that they'll whine- is that due to the clutch action loading the position of the engine, or is the dynastart is fixed in relation to the engine? 

Also, if they sit too deep in the pulley they howl very badly- that's what I had with the fan belt on the Pontiac.

A wider belt helped me but the pulley faces being a little worn with age are no longer straight, but form a shallow arc which doesn't match the profile of a new belt. The result is the belt doesn't drive on the flat upper section, instead using the ribbed inner part to translate the load.

Gentle but judicious use of a file with the engine running to slightly reduce the width of the bottom inner edge of the belt resulted in no reduction in grip but blessed silence.

[Zelandeth]

7 hours ago, PhilA said:

Good luck with the dash- I remember the similar fun I had with the Renault.

Re: Invacar belt noise- with ribbed/bladed belts if they sit at a slight angle like that they'll whine- is that due to the clutch action loading the position of the engine, or is the dynastart is fixed in relation to the engine? 

Also, if they sit too deep in the pulley they howl very badly- that's what I had with the fan belt on the Pontiac.

A wider belt helped me but the pulley faces being a little worn with age are no longer straight, but form a shallow arc which doesn't match the profile of a new belt. The result is the belt doesn't drive on the flat upper section, instead using the ribbed inner part to translate the load.

Gentle but judicious use of a file with the engine running to slightly reduce the width of the bottom inner edge of the belt resulted in no reduction in grip but blessed silence.

There's no fore/aft adjustment for the dynastart as such, but there is potential for a bit of movement depending where you have pressure on it when tightening bolts up - it does seem to be a lot quieter now so we'll see how it goes.

 

You know I said I was going to be leaving the graphics work for a while?  Yeeeah...

The result:

Everything is on separate layers, so I can have a play around with different options regarding getting a clean print, good colour purity etc.  Just need to wait for the transparency sheets to arrive.  Fun fact: Laser printer transparency sheets are expensive suckers! 

There are quite a few imperfections, I'll need to tidy up a couple of the legends (sidelights and glow plugs being the two which stick out at me the most).  A lot tidier than what's in there at the moment though.

[PhilA]

Why does it have capacitor warning?

[LightBulbFun]

17 minutes ago, PhilA said:

Why does it have capacitor warning?

[Zelandeth]

32 minutes ago, PhilA said:

Why does it have capacitor warning?

Because Citroen couldn't resist using their own symbology for at least something...

That's the warning light to tell you if there was something amiss with the semi auto gearbox - or possibly was just an overheat warning for the clutch on it... can't remember the precise wording, but it was something to do with that!

[PhilA]

2 hours ago, Zelandeth said:

Because Citroen couldn't resist using their own symbology for at least something...

That's the warning light to tell you if there was something amiss with the semi auto gearbox - or possibly was just an overheat warning for the clutch on it... can't remember the precise wording, but it was something to do with that!

I believe the ISO would be a cogwheel with a thermometer in the middle.

[Zelandeth]

14 hours ago, PhilA said:

I believe the ISO would be a cogwheel with a thermometer in the middle.

That's certainly the one I remember seeing on the dash of Leyland Olympians.

The alternative answer for the BX one of course is that it's a warning to tell you that the plutonium chamber is empty.

-- -- --

Well today has been spent generating this mess.

Last couple of trees that need to come down are going to require access from the other side of the fence to remove the bulk of the weight before we can bring them down.

Have got a mechanical job out of it though, the exhaust decided to fall off the chain saw.  Gaskets have had it, so possible it's been leaking for quite a while.

The marks on the back of the silencer and heat shield certainly suggest that theory.

New gaskets and some locknuts on the studs this time so it can't unbolt itself again and we should be good to go.

Now however I am utterly broken, and will probably be feeling that way for most of the next week!

 

 

[Tadhg Tiogar]

On 9/17/2021 at 2:24 AM, Zelandeth said:

....The single biggest cleaning task I was worried about though was the bit of plastic which has that diagram of the car printed on it.  The plastic is edge lit and provides a light pipe effect to make the diagram glow.  If that came off I'd be stuffed really, I don't have the resources to remake that.

Thankfully this was the result of ten minutes of VERY careful cleaning with a microfibre cloth.

Jumping ahead a bit, here's how this area now looks when lit up.

Far less blotchy light coming through from behind and it's way brighter now as the plastic is clean.  The bezel isn't fitted there so there's a lot of spill from the sides......

Did I post this specialist plastics supplier link earlier? Couldn't remember if I had.

[Zelandeth]

1 minute ago, Tadhg Tiogar said:

Did I post this specialist plastics supplier link earlier? Couldn't remember if I had.

Quite possibly, I definitely remember seeing a link to one somewhere!

Thankfully I don't need it as the plastics themselves are all okay, just covered in an oily film which I have now successfully removed.

Did another recording of the fleet update video today...and it's utter crap.  Fifteen minutes of me going "Uuuuhhh..." And repeating myself.  Blarg.  Guess that's what I get for trying to adlib while tired.  Think I need to try to back up a bit and do a shorter segment for each car...and give myself a brief set of bullet points beforehand. 

[dollywobbler]

Good work. Pretty sure there was never a BX semi-auto though, just manual or auto? So that lamp is a bit baffling. 

[Zelandeth]

2 hours ago, dollywobbler said:

Good work. Pretty sure there was never a BX semi-auto though, just manual or auto? So that lamp is a bit baffling. 

Hmm...just looked at the handbook I printed off for it and there's no mention of it in there at all!  Wonder if like the blue temperature light if it's something that was designed in then never used then.

[Zelandeth]

Quick job to tidy up the BX dash completed, sanding back and repainting the speedometer pointer white.

Which looks a good deal brighter back in the panel.

Another bit of BX was obtained and fitted today too.

That's right, she has a parcel shelf now.  Yes it's black rather than beige, but it's less jarring than if it were blue or something like that.  I'll take the wrong colour over "missing."

Means the junk in the boot is less obvious!

Small details yes.  Though I still see it as important as the less things which are missing, the more likely my enthusiasm to keep pushing forward on getting the car sorted is to continue.

Has it helped take the rate the thing hurls itself open at?  Nope...it still wants to smash my teeth out!

The Jag's alternator lately has been behaving itself - right up till this afternoon.

I'll need to see if I can get the brush pack out with the alternator in situ (as I *really* don't want to have to mess about with the belt tensioners again).  It doesn't actually look too hard to get at by the standards I'm used to on this car.

I'm sure I'll end up swearing a lot at that power steering lines a lot though...

From the symptoms I'm hoping it just needs a brush pack as I really could do without spending on a new alternator on this right now...

[Zelandeth]

Actually had a few consecutive hours available today so flipped a coin between pulling the alternator on the Jag (which has of course started working again) and delving into the diagnosis of what's going on with the Merc.

Merc won.

Step 1 I decided was to have a proper look at the camshaft.  I knew a couple of lobes were badly scored but wanted to see what state the bearings were in - I had a feeling they were likely to be shot and haemorrhaging oil, hence the less than stellar pressure at a hot idle. 

Off we go again.  Getting used to doing this now!

Number 1 cam rocker assembly off revealed...

An impressively scored up bearing with a lot of slack, which you can actually see looking closer.

Don't think I need to get a Plastigauge out to confirm there's too much free play there.  You can easily get a fingernail into the gap.

The cam followers feature some epic scoring too.

 

Number 2 was pretty similar, though with slightly more severe bearing scoring, cam followers were *slightly* less mangled.

This was the first one where I couldn't remove all of the bolts from the rocker frame itself because of how much carbon buildup there is in the bolt holes!

Number 3 however was where things got real exciting...

The cam followers are utterly wrecked, both inlet and exhaust.

That however pales into total insignificance compared to the state of the camshaft...

Wait...that doesn't look right, let me move a bit to get a better look...wait...what the?  Oh fluffing hell...

Yep... pretty much the entire cam lobe of the number 3 inlet valve has been totally *obliterated.*

I'm pretty certain this is the most mangled non-broken camshaft I have ever seen... it's *definitely* the worst I've ever seen on a running engine.  Never mind one that seemed to be running quite happily aside from being a bit rattly.  That's easily 5mm plus change of material that has been worn away.

Number 4 also has quite a lip on the exhaust valve...which would have been impressive wear if we hadn't just seen the above photos.

The followers on this one were probably the least badly deformed of the lot, though that's not saying much.

Goes without saying that the whole camshaft assembly inboard of the timing sprocket is scrap metal.  Well I don't think it is actually...this is more the sort of artefact that should be hung on the garage wall as a warning to future generations!

I did start the engine up with the rocker cover off briefly simply because I wanted to confirm we did have good oil flow up there, as there's obviously a load of damage been caused by oil starvation or *severe* contamination.  We do - in fact so much oil is gushing out from around the rear two and front bearing that it totally overwhems the drains in the respective areas of the head and starts flooding over the top of the head after the engine has been running for about five seconds.

Probably why everything under the car looks like this.

Definitely plenty of oil getting to the camshaft now...

Though sadly too late, this hardware was mortally wounded years if not decades ago.

There's like 1/8" of this gritty sludge just caked over everything.

If you remember back to when I first set the valve clearances I checked and found that the spray bar which runs above the camshaft was about 70% clogged, with the front most jet being the only one that was working properly.  This ties in with where the most damage seems to be...so I'm calling on oil starvation as the main cause.  The lack of zinc additives in modern oils probably hasn't helped given the cam follower design.  A separate additive will definitely be going in with the oil once this mess is sorted out.

It's a bit hard to see, but in person you can make out glittery residue in the head valley around number 3 far more than anywhere else, which supports the thought that the mangled camshaft may be where a lot of the glitter I found in the oil had come from.

So if the bottom end has survived, we might just get away with a head swap.

Before going all the way down that lengthy road (being used to OHV engines a head swap on an OHC engine feels daunting!) I'd really like to take a look at the condition of the engine bottom end.  Simple enough to get a quick health assessment done, drop sump, pop a couple of bearing caps off and see if we can see copper and if the crankshaft looks smoother than the surface of the moon.  Simple enough.

Oh.

How the bleep do you get the sump off this thing?  There's a stinking great cross member in the way.  Sump appears to go back to about the red marker in this photo, a good foot or so behind the front of the aforementioned metalwork.

Even if I could figure out how to get to the half dozen or so bolts buried above it and removed the engine mount attached to it... I'm not convinced I'd have enough clearance to pull it out.

Think I need to go do some reading to figure out what really simple trick it is that I've missed...or getting the sump out will wind up with me 3/4 of the way down the road to removing the engine...by which point I may as well just take it out anyway!  Feels like I must be missing something though given how serviceable most things on this car seem to be.  I did wonder if the sump was split into a front and rear half, but if so I can't see the join.

Definitely an instructive day...and kinds good news in a way.  The camshaft being so chewed up to this extent definitely would have an impact on oil pressure I'd think and we've definitely found a likely cause for the glitter.  It's just possible the bottom end might have survived...

Either way I want to check the condition of it before going to the trouble and expense of a head swap.  Plus given the amount of grime in and around the top end I fully expect the sump to be as bad or worse...and worry about the oil pickup strainer.

Now I just need to figure out how the fluff to get the sump off!  Simple right?

[Six-cylinder]

That camshaft looks hideous!

[J-T]

Jesus, that cam!!

As I recall it didn’t sound particularly bad either - slightly tappy. It still seemed to drive well too! It must have gone tens of thousands without servicing.

[GrumpiusMaximus]

What the?  Wow.  I think that camshaft out to be framed or used as some kind of furniture piece.  That's seriously impressive.  And even more impressive that the car is still running.

You can see why they're used as taxis all over Africa, thirty years and change after production!

[Zelandeth]

Is there an easy way to get the sump off?  Looks like no.

Mercedes simply didn't see any reason it would need to come off during routine maintenance.  Not unreasonable to be honest...especially being an aluminium sump so it's not going to rust through.  The expectation simply is that it doesn't need to come off unless you're doing a rebuild, and if so the engine would be out of the car.

It seems like it is possible if you have it on an engine crane, undo all the engine mounts and lift it about as far as you can before the gearbox fouls on the bulkhead...but even then it's a fiddly swear fest of a job...and getting it back in is an order of magnitude worse.  Plus by that point you're the best part of 3/4 of the way to having the engine out anyway...

 

Need to have a think.

[cort1977]

Depends on clearance obviously but in the past I have changed out the sump gasket by carefully jacking the engine and putting blocks between the mounts and crossmember to support it.  Clearance became very tight and you have to watch the fuel hose etc but I did get it done in the end.