Picture of Rotor Arm position at TDC

[Classic_Cars_Dubai]

Hey Guys
  Looking for a bit of advice on a where the Rotor Arm should be pointing where the engine is TDC. The MB is a correct 280SL with an 051 Distributor with Vacuum retard and currently pointing nearer to the 4 o'clock position when i get it to TDC and I have read it should be 2 o'clock.(When i reference the clock # position, I would be standing in front of the car and 12 is obviously facing the windshield). The car is running and will start up, but seems to have a small piston misfire after it warms up.

 I cannot find a picture to reference, so would anyone have one? 

Thanks,

[Benz Dr.]

Do you have a timing light? You should set your timing to around 8 degrees BTDC at idle and should have around 38 degrees BTDC at full advance with vacuum connected.

[Pawel66]

When you remove the distributor cap and look at the edge of the aluminum housing, you will see a mark on this edge, a small cut. That is where the rotor should be pointing (more or less). When you set it there, check if you are on TDC cylinder 1 (just in case) - try to look through oil filler opening in valve cover to see if both cams on cylinder 1 are up, meaning both valves are closed. Then also the mark on the pulley that you use for setting the ignition timing should be somewhere around 0 (give or take 10 degrees).

You see the mark on the picture next to condenser (it may not always be next to condenser!). It may be bigger cut or smaller - depending on the distributor.

What you can also do is to follow the ignition lead from spark plug in cylinder 1 to the distributor cap - it will go to one of the connectors in the cap. The rotor in TDC for cylinder 1 should point to that connector for lead from spark plug in cylinder 1 (when the cap sits on the housing with its lip in the slot for it in the housing).

[PeterPortugal]

I had to re-orientate my distributor as you suggest.

I moved the distributor so that the rotor arm pointed to the mark when No1 is at TDC as shown by Pawel. Then I had to move my plug leads around to make sure No1 lead was also synchronised with this position.

Then I set the timing up as Joe described. Just a slight tweak was required.

i am not saying whether 2 o'clock or 4 o'clock is right for you as my car is a 220se.