Note If you are atisipating undertaking jobs where the power train has to be removed from the vehicle then Lofty's DVD has files that will detail the procedures to be followed. as well a large number of other workshop files.
I was driving out from my work one afternoon and as I was accelerating out of the driveway the engine revved significantly and the car appeared to loose forward traction. Over the period of getting home with a number of stop starts the shuddering on start-off progressively worsened to the point that it felt unsafe to drive.
Having just had my son's Mitsubishi Lancer Cedia transmission fail with a similar set of symptoms, I figured out fairly quickly that the K1 clutch in the transmission had probably failed (i.e. cracked housing preventing enough hydraulic pressure being applied to the friction disks for the clutch pack to work properly).
I rang a transmission repairer the next day and was quoted $5000 NZ to repair i.e. the value of the car. Given that the car was now effectively worth scrap value, I decided to give replacing the K1 clutch a go as driving it would be too dangerous i.e. effectively the car had next to no first gear.
Having decided to have a go I thought that I would document the steps (as best as I can remember) to show that a reasonably major job such as this is possible for the DIY mechanic. The only device that I had borrow was an engine lifting frame.
All the other tools used were hand tools that a typical DIY mechanic would probably already have or were inexpensive to purchase.
Parts, Cost and Time
I purchased a complete K1 clutch pack from the UK for around $500 NZ (£229.99)from Chris @ Autolink Automatics Ltd via uk.ebid.net (Note: This clutch pack is the newer design and looks significantly more sturdy than the original removed from the car).
The dealer pricing was $1500 for the same part. While the car was disassembled, I decided to also replace the V-Belt and idler pulleys and I brought these direct from the dealer. Post assembling the car and after driving it for 100km with the original transmission fluid, I also changed the transmission filter and fluid.
All up the repair cost around $1200 NZ and took me around 50hrs of effort spread out over a period of around 1 month.
The shaft containing the K1 Clutch Pack is called the "ounter Shaft" I used a gear puller to remove the K1 clutch pack intact (after using circlip pliers to first remove the circlip retaining the clutch pack on the counter shaft). It was not pressed on to the counter shaft all that tightly so came off easily.
This photo shows the damage to the clutch pack, the crack extends nearly half way around the circumference of the clutch pack shell.
Be sure to note where everything in the transmission should return as you pull it out. Taking photographs with a digital camera at each stage will greatly assist you if you are in doubt. There a number of spacers, roller bearings, pins and other bits that are pretty easy to lose track of where they belong when you come to re-assemble. Once the transmission is open it is VERY important to keep dirt out of it. I cleaned around the two halves of the housing to make sure that dirt did not ingress when the housing was separated. I also made sure that my work area was very clean and inspected the transmission thoroughly for dirt before restoring the torque converter housing. I did not open the valve block cover during the repair process (there should be no need to do this).
Work to be undertaken prior to being able to undertake this transmission repair
It should be noted that before this repair can be undertaken the complete power train (Engine complete with gearbox ) has to removed from the vehicle.
This can one be done by lowering the complete engine and gearbox from below the car's bodywork, engine bay
The complete unit can be lowered on the front subframe but ideally needs to be supported on a frame secured to the lowering devise.
For full details of the procedure consult a Mercedes Benz workshop information system, or purchase Lofty's DVD on which the information is available. for purchase details of DVD.
or see more details below:-
Mercedes A160 Cassic K1 Clutch replacement.
Thank you Robin for providing this information.