I'm in the process of adjusting the preload on the hydraulic compensators on my 1977 450sl (a real treat to drive). What and absolute PITA. I'm sure it is solid once done, but getting there is a real journey. Any one devise a method of pressurizing the oil system to avoid having to keep cranking it before taking a measurement? I bought a tester that looks correct for this engine, but it does not match any numbers I've seen on the Forum. I have a stamped 9175890623 tool. Ring a bell of anyone? Perhaps a later tool code change? If not for the 450sl, what engine is it used for? Perhaps someone would have a better use for it. This car is teaching me a LOT of things I obviously missed growing up...and that's been awhile. Wife says I never have grown up. Thanks for your input.