300SL misfire / hesitation

[LeighW]

Any ideas on cause of this please:

I took my girlfriend's late grandad's SL for a run today, it hadn't been started since late November (see this thread.) The battery was flat, despite being left garaged and on a trickle charger. One quick swap with the one from her grandma's C240, and after a few turns of the starter, it was running perfectly. I took it for a short run up to the local Halfrauds to price up a battery (£99.99!) and all was well for a couple of miles. However, when I restarted it, it started to hesitate and misfire at low revs. It's fine above 2.5k revs, but when you open the throttle to pull away from standstill, or blip the throttle sharply from tickover, it struggles. Once it's moving, and above 2.5k revs, it seems ok. Any ideas folks?

It's the M103 12v motor, if that helps.

 

[grober]

Condensation inside the distributor cap would be my guess. Heat soak from the newly warmed engine was enough vapourise some liquid inside the distributor which coated the innards with a thin film of water. Take it off and give the distributor body and cap a good blast with a hair drier. Other possibility is dodgy fuel have sat so long.

 

[Sp!ke]

Distributer cap or plug leads for me too.

 

[Druk]

Certainly the dizzy cap. Drying it doesn't work long term, get a new one and the O ring it sits on.