I have a compression tester with adaptors for most engines. This tool is basic, and only needs to check pressure. As for the listen-as-I-crank method--- On any given engine, I do whatever it takes to not have the engine start while I crank it. On a gaser I unhook the power to the ingition. On a diesel I stop the fuel, even if it means loosening the lines to all the injectors so they can't get fuel. Then, crank the engine and listen. As each piston comes up on compression in succession you will hear it as the compression slows the crank speed a little. If this sound is the same throughout perhaps 4 or 6 turns of the engine (2 or 3 complete cycles) than the compressioin is uniformand and all cyls. are the same. This doesn't mean they are good enough. In most cases if the engine starts ok, than the compression is at least ok for moderate driving needs. If however while cranking you hear a periodic change in sound (if the starter seems to speed up perhaps every 5th compression stroke) this indicates extremely low compression on one cylinder. Sometimes a valve adjustment will restore compression. Sometimes they need a valve job. Other times If you see large puffs of smoke at the oil filler cap (cap removed) all of that compression could be passing by a piston. If this helps a little, but...... get back to me at gbkramer2000@yahoo.com