Constant Speed (Lifting) Solenoid

[Richard Madison]

I think the CS solenoid in manual cars is to maintain idle speed when the AC kicks in. The wire from my '71 280 solenoid has never been connected. I'm about to revive the AC (I hope) and wonder if it is important to have this solenoid working.

I read that in manual AC cars, the solenoid wire goes to an AC box. I found a fuse box for the AC (I think) on the passenger fender wall. It has one fuse and four screw connectors. A red/green wire goes to the wire loom and the other wire from this small bakelite fuse box goes through the fire wall (to the AC switch?)

Anyone know how to wire the solenoid in a manual AC car? Is is important? Photo of the tin can solenoid is attached.
Thanks
Richard M

Download Attachment: mb_CSsolenoid.jpg
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'71 280 SL, Tobacco Brown, Cognac interior, Tan top, Jump Seat, 80K orig miles, NYC.

[Cees Klumper]

Hello Richard - it is in fact important for the solenoid to work, since it is necessary to keep the idle speed constant when the AC is turned on. Without it, the idle speed will drop too low (couple hundred RPM difference). Same reason the automatics have this solenoid. I am sorry but I don't know how it should be wired. I hope yours works properly, since they do wear out, are almost impossible to repair for us shade-tree mechanics, and new ones will cost around $300 (at least here in the Netherlands). I read somewhere many Pagoda owners have converted their AC compressor to a more modern (York?) type that is apparently more efficient.