The big ticket item though turned out to be the water pump. For a long time there has been an intermittent soft squeak noise in time with one of the cylinders firing only when the engine is hot. I had the hardest time tracking down what it was and was beginning to suspect I had a wrist pin squeaking or a camshaft bearing trying to seize.
Nope.
It was the water pump bearings. When I had the belt off to do the OAP, I spun the water pump and was rewarded with a horrible rumbling noise with a squeak as it came to a stop. Great......
Reading up in the FSM on how to do the job, it didn't seem like a big deal, just spin off the fan clutch, remove the pulley, and unbolt the pump. Easy right? Wrong. Apparently the fan clutch had been replaced at some point in the past and the monkey that installed the new one had Hercules tighten the bolt. There was no possible way it was ever coming out with mere mortal tools. Read about that clusterf**k here:
603 Fan Clutch Bolt Rounded Out - Now What...
Since I had to ruin the clutch to get it off, I decided it was prime time to upgrade to the OM606 11 blade fan and clutch from a '99 E300D. The 606 parts will bolt up to a 603 no problem and the later clutch cuts in at a lower temperature than the original 603 part did.
The interesting part is that the 606 fan FEELS heavier than the original 9 blade aluminum fan, but it's 1/3 of a pound lighter! I finally got the parts in today and got the car back together and back on the road. After driving the SL and the Honda for the last 2 weeks, it's remarkable how smooth and quiet the SDL is in comparison. The SL is a bit rough and ready, but the Honda is pretty smooth and refined. The SDL is in a whole different class...
The good news is that there's no leaks (yet) and the engine is SOOOOOO quiet when on the road. It's amazing how much noise that water pump was making! It just sounded like engine noise!
I also did an experiment with a P/S leak. The return lines were all leaking at the clamps. Having been through that mess in the SL, I didn't waste my time tightening them, I just replaced them all with worm clamps. That stopped that leak, but I had another unusual leak on the steering box itself. No leaks from any of the shaft seals, but it was leaking from the joint where the top plate bolts to the box itself. Weird... I drained the P/S fluid out and refilled with Valvoline Max-Life ATF and half a bottle of Lucas P/S stop-leak. Time will tell the tale, but for now it seems to have stemmed the tide.
And of course this evening, the brake lining light decides to come on as I come to a stop at a traffic light. Looks like front brake pads are next on the agenda. It's always something...