The bleeder bolt mounted on top of the M103 head is made of very soft metal.

Can you say strips-real-easy.

Forget that and simply refill thru the coolant overflow tank with t-stat out. Once you have fluid at the top of the t-stat housing - most of the air is out of the system - not all - but most.

Put the t-stat back in and fasten t-stat cover.

Leave cap off overflow tank - start car - allow to reach normal operating temp - heater on. Attach a sock to the part of the overflow tank where the radiator cap is fastened.

Blip the throttle several times with a short rest between blips. This allows the water pump to push coolant thru the system and residual air exits out the coolant over flow tank opening. The sock keeps the coolant being pushed out from getting all over everything.

Top off coolant if necessary and refit coolant overflow tank cap - otherwise known as radiator cap.

You may need to top up some more a day or two later after things settle down.

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"