The SLS on my newly acquired 81 300TD wagon is inoperable. There is fluid in the front reservoir. I put the car and ramps and moved the control arm that connects to the rear sway bar to operate the SLS but nothing happened. I held the arm all the way up and down for about a minute in each position with the car idling. No noise, no movement.

My trusty Haynes manual says I should take it to the shop due to the need for specialty tools. That isn't going to happen. Does anyone have DIY diagnosis and repair advise?

Thanks,
Glenn

When your car is idling can you see hydraulic fluid being returned to the resevoir thru the dipstick hole? There is a filter in there that could be clogged. You might try changing out the fluid and fiilter then retesting. The accumulators are also known to go bad-not sure of the exact test. On mine I had to rebuild the valve-there is a thread on here somewhere that explains it & the dealer sells the parts for like $70. good luck!

I will have to check on the filter being plugged. Thanks. I found the thread about rebuilding the valve.

If I can see fluid being returned, then what? I just don't want to keep throwing $$ at parts until it is fixed. Any way to test the struts or accumulators individually to determine what exactly needs to be repaired? The only thing I could think of was being able to see leaks, but everything (struts, accumulators, pump, lines and valve box) all looked free of leaks.

Thanks,
Glenn

Check for the fluid return. And check the filter. I doubt that the filter is so clogged that it is stopping the fluid. It is a spring attached filter. If clogged the spring will give to allow it to flow.
So check to see if the filter is ok. See if the fluid it returning to the reservoir.
If not then we must check the pump. You can disconnect the lines and see what fluid movement is occurring. If non then it is the pump. If it is moving fluid then it is the control valve OR a blocked line. The accumulators will not interfere with the control valve and struts, only the ride quality.
Fluid is pressurized from the pump. routed to the control valve then the accumulators then the struts. The return goes from the struts and the control valve to the reservoir.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car

Finally looked at the SLS again last night. I have fluid flowing through the filter and back into the resovoir. So that leave a blocked line or a bad control valve. (This is assuming that since I don't have bad accumulators or struts just because they don't leak.) I am open to suggestions to check for a blocked line. Do I just loosen the return lines on the struts and see if fluid comes out?

Thanks,
Glenn