1800 rpm idle

[glennard]

Problem: 230SL idles at 1800 rpm after backing out idle screw and making sure CSV does not leak. Anybody ever changed stop bracket on throttle shaft on the FI pump or altered the clamp to the throttle rod on the shaft to slow 'er down?

[Ben]

Why did you back out the idle screw ?

I'd first suggest, as usual, that you ensure your timing and dwell are spot on as any adjustemnts are futile without this being correct first. Then ensure the venturi plate is fully closed, take the air filter rubber hose off and peer in. After this ensure the linkages are set correctly as per the details in the "How to" section !

If you've done the above and still have a high idle then try turning the air screw on the inlet manifold all the way in. This should stall the engine and if it doesn't then you have a vacuum leak, air is being drawn in somewhere, either at one of the fittings or gaskets.



Regards,
Ben in Ireland.
'64 230SL 4sp.
'03 CLK Kompressor

[ja17]

Hello Glennard,
The injection pump arm should not be tampered with. It has a sinch bolt arrangement and if you loosen it things will shift inside the injection pump and you will need to remove the FI pump and have it re-calibrated. One lister has already made this mistake a few months ago. The later W113 cars had this linkage arm fused from the factory so it could not be altered.
 My frist thought on the mater is that your intake  venturi valve is not closing all the way. Make sure the 10mm linkage nut and slotted screw are backed out enough for the flap to close all the way . Do a search on this there is a lot of information on the subject. If this is not set correctly your engine will be allowing too much air into the intake and the idle will be way to high.
Let us know if you do not understand any of these terms or concepts and we will help you through with pictures, diagrams and whatever! Good luck.


Joe Alexander
Blacklick, Ohio