I just finished replacing a pump on a 280SL with a rebuild from Pelican Parts/C&M Hydraulics. I ran into some issues that may come up for others.
1. The pulley would absolutely not come off in the car. For an unknown reason, on this car, I could not get my long hex bit socket through the bracket and into the inside screw. In this case you need to remove the harmonic balancer and use an Allen wrench on the screw.
2. There are 9 mm four bolts that hold the halves of the pump together. One is longer and fits through a hole in the rear of the bracket and threads into a hole in the front of the pump. The rebuilt pump had the three shorter bolts, but one was occupying the hole used with the longer bolt. I had to relocate it. Best to do this before you put the pump in the bracket!
3. The above bolt that came out car was 10 mm x 65 mm with a 17 mm head. The rebuilt pump would would only accept a 9 mm bolt. The 10 mm bolt would go into the hole, but not thread. Fortunately, I had a 9 x 65 bolt on hand. Checking the EPC, the bolt is 10 x 65- N000931 010110. I looked at a third pump, and the 10 mm bolt would not even go into the hole.
Hmm. I can't explain this and only suggest that you be prepared when changing pumps.
4. Not only would the pulley not come off in the car, but I could not get it off with a fairly large puller on the bench. I took it to a machine shop and their puller broke trying to get it off. They ended up cutting it off with a carbide burr.
Never a dull moment,
CT
