Hi all! I own a 1970 Mercedes 250c. I have searched this forum as well as the rest of the net for info on my particular problem but have not had any luck.
I have just had my rear main seal and crankshaft/flywheel replaced by a local mechanic. I also purchased the Redline Weber 38/38 DGES carb kit and he installed those as well.
It feels as if there is something preventing the throttle plates from opening slowly and easily. I'm guessing vacuum pressure (?). I have to use much force on the gas pedal to break through this resistance, causing the engine to rev. It's either off or on, making driving very uncomfortable.
I have gone through all the linkages and they do not bind. The accelerator return spring at the firewall has been removed. In fact, this only happens when the engine is running! Pressing the pedal is nice and easy when the engine is off.
The mechanic did not utilize the heat shields, so I am left with an extra spacer for each carb. Will that extra 1/4" of space between the throttle plates and the manifold make any difference?
What I can say is that opening the throttle plates by the turning the idle speed screw in makes a difference (decreases the resistance), but at this point the idle RPMs is too high.
Any ideas? Thanks much in advance.