1963 Mercedes Benz 190DC Fintail. Big oil leaks.

[Talbot]

That axle leak is quite bad actually, and will likely have soaked the brakes.  You've a few options:

Fit replacement rope seals, which will then last for a good few years again before needing another overhaul.  But they will always weep a bit and be vulnerable to drying out.

Re-engineer the rear axle to accept rubber lip seals, which will take longer but then likely last the next 20+ years of service (or more) and won't dry out over the winter.

First thing to do is strip the axle end down and investigate.

[Dyslexic Viking]

6 minutes ago, Talbot said:

That axle leak is quite bad actually, and will likely have soaked the brakes.  You've a few options:

Fit replacement rope seals, which will then last for a good few years again before needing another overhaul.  But they will always weep a bit and be vulnerable to drying out.

Re-engineer the rear axle to accept rubber lip seals, which will take longer but then likely last the next 20+ years of service (or more) and won't dry out over the winter.

First thing to do is strip the axle end down and investigate.

This is a seal kit on the axle against the brakes. No rope seal.

 

I have those gaskets and wheel bearings for both sides. And the brakes have been fine and without oil contamination last time I checked as the oil just drips out and runs down the back plate and out a drain hole and then onto the rim. But I need to do something about this and would prefer to try to get help as I hate drum brakes so much and don't have a press.

[Talbot]

Oooo!  If they are a lip seal from new, then you can just pry the old one out and shove a new one in.  there's a good chance that the one in there is the original from new, so a new one now should last until 2089.  (63 year lifespan, clearly!)

[Mr Pastry]

The first thing to do is to check that the axle breather isn't blocked. It might just be pressurising.

[Dyslexic Viking]

2 minutes ago, Mr Pastry said:

The first thing to do is to check that the axle breather isn't blocked. It might just be pressurising.

Yes, I disassembled and cleaned it a year or two ago.

[Dyslexic Viking]

I have decided to give the axle shaft seal on the right side a try, something I will probably regret in the future but I will try to be positive for now.

So I've been out moving the car and getting everything ready so I can just start when I can. I have no idea how long the axle will be but I've measured that it's a little over half the width of the car on the right side which hopefully is enough if not I'll have to saw a hole in the wall.

[rusty_vw_man]

Just catching up on this - I’d monitor the engine leaks, if they get so bad you have to top the oil up mid trip it might be worth looking at! I agree though that the axle seals need a look at.

My experience of axle seals is that it’s getting all the bolts undone that’s the tricky bit, but it’s all quite simple. Photos of everything is the way forward so you can check the order and way round of the parts as you reassemble. 

You can post the pics here so we can follow along! 

[Dyslexic Viking]

I had time today to start on and trying replacing the leaking axle seal.

It didn't go so well so after talking to the local garage, it's scheduled for May 13th and someone more competent will work on it then.

And for some inexplicable reason, the brake is now hanging a bit (there is no adjustment) so because of this the car will not be driven until it goes to the garage.

[Dyslexic Viking]

One question, has anyone here ever messed with the timing chain tensioner on an old Mercedes engine? Like W123 and older.

I let the engine idle for a bit today and noticed that the oil leak from the timing chain tensioner is bad now. And struggling to find any info on how difficult it is to take it off and put on a new gasket or o-ring. I assume the chain must be held tight while removing it but no idea how.

[Dyslexic Viking]

I should give a little update here. This was delivered to the local garage on Wednesday to fix the oil leaks on the rear axle. It turned out to be a struggle and they couldn't get it done and it was a long weekend so I got it back yesterday. Now the axle seals and wheel bearings on both sides at the rear should be replaced and the seal against prop shaft should be replaced. It also turned out that the propshaft had some loose bolts that were almost worn off that got replaced so good they discovered that. Haven't gotten the invoice yet but when I do and when I can look over the car I'll know a little more. Need to take a quiet day after having two big teeth pulled yesterday.

[TrabbieRonnie]

1 hour ago, Dyslexic Viking said:

I should give a little update here. This was delivered to the local garage on Wednesday to fix the oil leaks on the rear axle. It turned out to be a struggle and they couldn't get it done and it was a long weekend so I got it back yesterday. Now the axle seals and wheel bearings on both sides at the rear should be replaced and the seal against prop shaft should be replaced. It also turned out that the propshaft had some loose bolts that were almost worn off that got replaced so good they discovered that. Haven't gotten the invoice yet but when I do and when I can look over the car I'll know a little more. Need to take a quiet day after having two big teeth pulled yesterday.

Brilliant news DV, you'll be able to relax and enjoy the car even more (it's only money! 😅).

 

[Zelandeth]

No idea if the diesels are different, but the chain tensioner on my S123 leaked like a sieve after I'd had it apart during a head change.  Originally they had a soft metal (aluminium?) washer behind it, which I nicked when reassembling it.

Couldn't find the part at the time anywhere - so went to my local hydraulics place and grabbed a copper washer with near as dammit the same internal diameter and thickness - worked perfectly.

If it's the same design removing the outer cap isn't a problem as the internals have a ratcheting mechanism so the tensioner itself can't move backwards even when the spring (which bears on that cap) is removed.  Backing the tension off requires the whole thing to be unthreaded from the block with a giant Allen key and dismantled.

The plunger is removed from the engine side and reinserted from the other end.  The mech only allows it to travel in one direction.

Caveat is I'm working on memories from 2022 here!  Also I've no idea if the same tensioner setup was used across petrol and diesel engines - and there's a 20+ year age gap.  Though Merc did seem to be fans of the "if it ain't broke, don't fix it" approach back then.

[Dyslexic Viking]

Thanks @Zelandeth that's good info, but unfortunately the timing chain tensioner on these is different.

Early version.

 

Later version.

 

And I have no idea what it has but I think the engine is newer than the car but I could be wrong. And I'm struggling to find any information on these on this. So I'm struggling a bit with what to do and I don't dare to disassemble anything here without knowing what I'm doing. But I'm going to study the timing chain tensioner on the car and see if I can see where it's leaking from.

[Stinkwheel]

Looks like both the older and nerwer version you have shown have an O-ring to seal them. Might be as simple as pulling it off and putting a new o-ring on. (fingers crossed anyway)

[Dyslexic Viking]

2 minutes ago, Stinkwheel said:

Looks like both the older and nerwer version you have shown have an O-ring to seal them. Might be as simple as pulling it off and putting a new o-ring on. (fingers crossed anyway)

Yes they have but I'm so unsure about removing this as I would assume removing tension on the timing chain will lead to bad things happening. 

Maybe there is a way to keep the timing chain tight while removing the tensioner, but I haven't found it yet.

[Zelandeth]

Oh well, was worth checking anyway!

Might seem a silly question - but have you tried contacting a dealership for info?  

Over here my experience is that Mercedes have almost uniquely been very good about trying to provide support for their legacy models.  Even when the parts in question were long since NLA, they were more than happy to track down the part numbers and give me printouts of the diagrams etc.

How far back that support actually goes, and if it's the same over there I've no idea.  It was something which came as quite a surprise to me though - and the parts supplied were really not at all unreasonably priced either.

It's something I honestly wouldn't have thought to check myself unless I'd been prompted to by another owner, so figured I'd pass that along too.

[Dyslexic Viking]

I called the local Mercedes dealer after I bought this and they just forwarded me to https://www.niemoeller.de/en and that place is terrible to navigate and find things. They probably have a timing chain tensioner for this one but good luck finding it.

[Zelandeth]

11 minutes ago, Dyslexic Viking said:

I called the local Mercedes dealer after I bought this and they just forwarded me to https://www.niemoeller.de/en and that place is terrible to navigate and find things. They probably have a timing chain tensioner for this one but good luck finding it.

That's a real shame.  I was really surprised by how helpful ours generally were.  

Looks like this might be your part.

https://www.niemoeller.de/en/ponton/w121-mercedes-190D-ponton/B110/050401/c05187-chain-adjusters

Or at least very similar.

Diagram gives a bit of a better view of how things fit together than just a photo in isolation.

https://www.niemoeller.de/en/ponton/w121-mercedes-190D-ponton/B110/050401#map-list