W123 280E oil leak

[Duke_Thrust]

Hello all,

I’m very new to Mercedes so please forgive me if this has been covered before.

I’ve just bought a 1980 W123 280E and am really taken by it – lovely car with bags of character.

It has a slight oil problem though insofar as it seems to leak quite badly. From what I can see it seems to be coming from the back of the block, possibly from the rear crank oil seal.

Is this a big job to change? Box out I assume?

Are there other possible causes/common faults for oil leaks?

Thanks for your help! :O)

 

[stever]

Check the rocker cover rubber seal for weeping first - easy & cheap to change.

 

[redmansioner]

Heave you checked first the Mercedes oil filler cap and rocker cover rubber seal?make sure it is sealed.It wont hurt you much if you take that change.

 

[television]

Is the leak from the top or bottom of the engine

 

[Duke_Thrust]

Seems to be a bit of both.

It looks like the bottom at the back, but last night I was topping the oil up and I noticed it was coming out of a small hole behind the exhaust manifolds in the head at the front.

There doesn't seem to be a thread in this hole and it was angled downwards - any ideas what this is for?

 

[Pontoneer]

It is very common on the M110 to have a leak between the bottom of the cam box and the cylinder head , usually at the front RHS above the alternator . These leaks can run along the engine and appear to come from somewhere else . If not too serious , many people just live with them and keep an eye on oil level .

The other common problem with the M110 is misfiring and crossfiring due to burning and incorrect routing of the ignition leads . As you will be aware , there is very little clearance where they run from the disributor cap , up and over the inlet cam side . Often the plastic clips which hold them in place go brittle with age and eventually break , leaving the leads flopping loose and often in contact with hot metal parts or with adjacent leads . This really makes a huge difference to the way these engines run and it is well worth replacing these items if broken - the clips only cost pennies anyway but they are often neglected . Be aware that ignition leads are VERY expensive to buy from Mercedes , but if you strike up a good relationship with the partsperson , you can obtain the ends and crimp them on to your own cable . The plug caps also tend to be expensive but can usually be salvaged .