560SEL further evaluation

After owning the 560SEL for a couple of weeks I’ve had a chance to spent a bit more time looking over the car.   I’ve also had a few more opportunities to drive the car – covering about 150 km over the time.   This is a lot less than I would normally want to do, but with COVID19 lockdowns, I can only drive the car for specific purposes such as driving to the shops to buy food.

First thing to do was to put the car up on the hoist and have a look underneath.   The car was ordered with a sump guard (W126 Undershields) and it is still there.  On a car this old it is not unusual for a forgetful mechanic to forget to re-attach the W126 undershields after work is done.   This was the fate of the front undershields on my 250SE.

Looking at the photo above, it is clear that the W126 undershields have done a great job of protecting the sump over the years.  Additionally, the car looked great underneath – no trace of any rust.    The flex discs also looked in good condition.    The kidney mufflers also looked new.

While I was underneath, I noticed one of the shift bushings was missing.   I had one on hand and replaced it.   The car was also missing two exhaust hangers.    I had one on hand so replaced that too.    At some point the rear self leveling suspension had been disconnected.   I wanted to see how this job had been done, and it looked quite neatly.

When removing the SLS, it is also important to change the springs, as the SLS springs are much softer.    I am really torn about this system though.   The car rides more harshly in the rear than it should.   When the SLS is working properly, it gives a really nice ride.   I’ve checked the parts catalogue and the struts are the same as on other 2nd generation W126s.   Here in Australia, all W126’s were delivered with SLS so used parts should not be a problem.    What gives me pause is that the struts (A116 320 45 13) are now NLA from Mercedes and Sachs.     I’m not sure if these are being rebuilt in Australia and for what cost.   I’ve seen some rebuilt units in the USA for eye watering prices.   For now, I have other priorities on the car.

Next task was to look at why the reclining rear seat is not working.    It is a trivial task to remove the seat bottom (two 10mm bolts) to see what is going on.   I first wanted to look at if any debris had fallen jamming the system.    Everything looked clear under the seat.    There is a central motor with two cables that connect to the rails on each side.

When I press the buttons on either door I cannot hear the motor at all even with the seat back removed.    I’ve checked the fuse diagram and the seat shares a fuse with the power windows.   This fuse is fine.   I also checked the wiring diagram and there is no reliance on other control units.    Right now my supposition is either the rails are jammed and the motor cannot turn,  there is a problem with the motor, or there is an issue with either the switches or power to the motor or switches.

My next troubleshooting step is to disconnect the motor from the rails and see if it will run.     Overall I am really happy with this car, it has clearly been looked after and while there are some short term things that need doing, I have a great base to start from.