Transmission slips - wiring?

[Kopie]

I am trying to sort out a recently purchased '71 280sl.  After getting the engine running, I'm experiencing extreme transmission slip in all forward gears.  Reverse does not slip.  I thought I would start with the Mercedes rebuilders site and have found that there is a wire disconnected from a switch or solenoid on the rear of the FI pump.  Is this the throttle body switch.  Also, the Mercedes manual diagram seems to refer to two wires connected to this.  Is there only one?  Any help or advice would be greatly appreciated.

[bpossel]

Kopie,

There is only one connection (one wire) connected to the rear of the injection pump on the later W113's, like yours.  That wire connects to the injection pump fuel cut-off solenoid.
Having this wire disconnected would not cause your issue (note: mine is disconnected and I dont notice any difference). The throttle switch is a different part.  The throttle switch is connected to the throttle body, close to the air filter canister.  The throttle switch has 2 wires connected to it.  http://www.sl113.org/wiki/Fuel/Throttle#Body

There is a procedure to correctly adjust this switch.  Refer to the Haynes manual, the BBB, or our tech manual.

Other info on transmission:
http://www.sl113.org/wiki/Automatic/Start

bob

[ja17]

Hello,

Remove the access cover inside the car on the tunnel  and check the transmission solenoid and its modulator  linkage to make sure they are free. They can be  stuck from storage. alsi check its fuse  to make sure it is getting power.

[Kopie]

Thank you both for your help.  I really appreciate it.  Now that I know where the items are located, I'll start my testing.  Does it sound like this could be causing the transmission slip?

[Shvegel]

Basically the solenoid controls the control pressure of the transmission. It has three positions. Low pressure so the engine isn't bogged down too much at idle. Normal pressure and high pressure which raises the shift points when you are at full throttle. If the linkage gets stuck it the low or idle position it will cause exactly the symptoms you describe.   Under the carpet on the right side of the transmission tunnel you will find a oval cover that will allow you access to the linkage.

[Iconic]

At the risk of sounding ridiculous ..... have you checked the fluid level.
I too bought a car, got the engine running, took it out for it's first drive, it slipped a lot.
Checked the fluid, it was low. For the record, I tried to check the fluid before I drove it for the first time, but the car needs to be at operating temperature to get an accurate reading.
Filled it up with synthetic RedLine D4 ATF (it took a little over a quart), drove it a while, and now it shifts like the best auto I have ever driven.
Good luck, whatever it is, you'll love it once you sort it out.
I apologize for making such a silly suggestion, but there are two ideas here. One is just the low fluid. The other is the synthetic RedLine. It might have freed up some components once it circulated around in the trans. (I do not work for RedLine, or profit in any way from the sale of RedLine products.)
Mark

[Kopie]

Well, no luck so far.  I checked power to fuse #3 and had power.  Checked the throttle body switch which works, but only engages if I force the throttle fully closed.  Linkage seems to scrape against the manifold shield.  Since the solenoid seems to move from idle to mid throttle, I went for another test drive and no change.  It still slips.  The linkage to the solenoid movies about a half inch in either direction.  Spark plugs are getting fouled black as if it is running very rich, but I can't take it for a long enough drive to see if it clears up, but #6 plug doesn't really seem any more fouled than any others.  The kick down switch isn't working now, but then I haven't been comfortable enough with the tranny to give it full throttle anyway.  The fluid level is full and clean.  I'm thinking at this point that it may better to take it to a shop unless anyone has other ideas that may help?