Could my noise be possibly caused by a blown head gasket? I ask because when I did pull the injectors there were at least 2 that were pretty wet down at the base. Should I do a leak down test on the motor? Like I stated previously the compression check showed 2 cyl. at 360psi. and they were side by side could that indicate a blown gasket inbtween them? Yesterday I ran motor which starts pretty fast and shot 1st marvel in the intake had no change of tap then I shot water in hoping if there was carbon buildup on piston head it would break it up no change in tap slowed engine rpm down to barely running no change in sound when I rev motor up pretty sure sound is still there but not as noticable. I have a feeling that if I go to pull prechambers out I will have a bear of a time as I still have an engine sitting on my garage floor that I never was able to pull the chamber out and think only way to get it out would be pull head from inside out. Would the Harbor Freight leak down tester be good enough to do this test?