Enrichment screw on rear of IP

[paults1]

Does the enrichment screw have a final stop when turning it ccw or cw? Or does just keep going around and around, going from lean to rich or rich to lean?  How many clicks are in the range?

Paul, early '63 230SL

[Cees Klumper]

I have read that turning the screw clockwise too far will result in it being engaged constantly, spinning along with the IP pump's RPMs - not a good thing. So a limit to enriching the mixture. I would imagine that there is also a limit to leaning it out, although I don't recall that having come up here before.

[paults1]

Thanks Cees for the info.  I still need to know the number of clicks or range.  I think it is not stuck on the full cw turns because I can feel the weights move in either direction.   Can anyone else help?

Regards, Paul

[al_lieffring]

There are 36 about clicks from full lean to full rich, In a prefect world the the pump was designed to run at the center position, 18 clicks from the full rich position, That is where I start when when making pump idle adjustments.

[paults1]

Thanks Al, this is the info. I needed!!

Regards, Paul

[ja17]

Hello,

Actually turning the screw (lean) counteclockwise (sitting in driver's seat looking forward) will cause the scew to wind out and start spinning. As the screw gets further and further out the clicks begin to disappear. Stop before this happens.

[paults1]

I hope I got it dead center, 18 clicks from the CW max rich setting.  Runs much better now. I still might have an issue with the  retarded retard 051 distributor.  Difficult to get the RPMS to stabilize when timing.  Might have to go with a 123 distributor & send the 051 to Dr. Benz.  Will know tommorw or Friday when CO test is done. Thanks to all of you for the help!!

Regards, Paul, '63 230SL

[stickandrudderman]

The clicking felt on the screw is a result of the screw being gripped by a spring. If you wind the adjuster too far the screw head pops out from behind the spring and you then have to dismantle the back of the pump to re-set it.