common oil leaks ?

my 124 would leak oil from the timing chain cover - would have cost to much to get it fixed tho.

has been known to be from a badly fitted rocker cover gasket....use a bathroom tile cleaner pump spray bottle with some petrol or heating oil in it and wash the back of the engine area clean and wipe dry.. then lay a white material underneath the area and observe the drip pattern.G should be on level ground with engine at running temperature. the bad news would be if it is the gasket between the crankshaft and the crankcase ..behind the flywheel....hows the oil consumption? and gearbox oil level ...if it is gear oil it will smell like cat urine....

the bell housing interface would tend to hold the oil in..we had heard sloshing sounds on idle and high revs with my son's 460 300gd 617 engine and found the bellhousing full of oil up to the bottom bolt holding the starter..... and there was no clutch slip either. cured it with a new crankcase seal and clutch kit but had to take the engine out to do it....

no ..there is no drain plug in the bell housing on the manual gearbox...if you take the starter off you can see if the pinion or the flywheel is wet with oil ...a good indication since that area should be dry....still look for oil coming from the rocker cover gasket and running back and down the side of the engine

this is a more common fault with the 280, with auto, oil drips into the start soleniod and buggers that up, i used to leave out the plastic bung of the bell housing to let it drain, then I never filled the engine oil more than 3/4 full. this helped but the 280 has a weak crank seal, as for the 300 I never had a problem other than the rocker cover weeping at the back.

From memory: the oil filter on a 103 engine is to the rear on the right side - the inlet side - cant remember anything on the exhaust side. The round thing at the front of the right side (from the front) is the power steering reservoir.

If your cam cover gasket is leaking be very careful tightening it up as its a aluminum head and will strip threads real easy requiring helicoil inserts to fix it. Like others have said the head gasket at the rear is a known problem. The rear crankshaft seal is a pain - need the transmission to come out to fix. A grove is often worn in the end of the crank and there is a bigger seal available to stop it leaking.

If you have got oil under the starter motor make sure its not running down from the head or cam cover and just dripping from the bottom.

How much oil are you loosing? if its not too bad you might be better to leave till you can get a head rebuild (if you want to invest a lot) my 103 engine only went to 89k before needing surgery on the head - ran beautifully afterwards and no oil leaks - well apart from drips from the crank seal which was fixed when the transmission was rebuilt.

If the oil is dripping from the oil filter housing it may not have been tightened up enough, my 300 engine has a paint mark applied in the body colour across the join, so I always tighten to this point and has never leaked (I presume this was put on by a Mercedes mechanic or from the factory) Same with my SLK there are marks on all the intake clips for the supercharger. When you change the oil and filter should be easy to fix.