I'd like to do an engine compression test on a 123.190 (1985 300 TDT) this weekend. I've searched the forum for compression test methods, but my question is a little different. I bought a diesel engine compression tester made by Rimac. I also bought the Rimac glow plug adapter as well as the fuel injector adapter. Most people talk about removing the fuel injectors, the fuel lines etc. Since I have the glow plug adapter, I think it's easier to just remove those and test compression from there. It's less work than removing the fuel lines, injectors, heat shields etc. I'll be replacing the glow plugs on this car anyway.

My plan is to: make sure the engine is hot; remove fuse to fuel pump (if the fuse doesn't control the pump-I can't remember between Volvo diesels and MB-then kill the fuel supply to the pump); remove glow plugs; screw-in adapter; attach gauge; crank engine between six-to-ten different times and record the readings.

What should the range be on each piston? 315? 425? Does this method sound feasible? Help and thanks!