Dear Joey no the pressure from booster pp was never checked,because we were told by mech. at several mack dealers that booster pp do not cause problem and they dont leak from the seals, so when we found out that was not true,just went and replaced it. But that wasnt the problem.YOU talk about a pressure regulator, where is that located?. yes the eups where all removed and the oring replaced twice but didnt pull the roller tapits. bad mistake.. allso missed oil sample being taken for several months. no broken bolts found, all bolts were torqued to lates spec. we still dont no where the fuel was coming from ? WHAT should the pressure be?.. Oh another problem, how the heck do you get the viberation damper and pulley off crank? done every thing book said ,dosent buge, cant find any way to put a puller on it,, tried putting a couple of falling wedges behind it and use a Big Fing hammer to no avail ..