Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision Both sides next revision
techtalk:ref:engmech02 [2019/04/12 02:14]
hippysmack [Hammer Performance Billet Base Kit]
techtalk:ref:engmech02 [2019/12/09 16:59]
hippysmack [Alternative to Stock Heads 1992 - 2006 Models]
Line 9: Line 9:
   * [[techtalk:​ref:​engmech02a|Screaming Eagle Pro CNC Ported Heads]]   * [[techtalk:​ref:​engmech02a|Screaming Eagle Pro CNC Ported Heads]]
  
 +===== Aftermarket Head Gaskets =====
 +Cometic MLS head gasket torque:
 +There are six torque values in sequence: 9-14-22-35-42-42 (all in ft/lb) \\
 +When using aftermarket gaskets, it's important to note that the torque values in the FSM are for OEM gaskets. ((Hippysmack of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​p=5793537#​post5793537)) \\
 +The OEM gaskets offer a squeeze factor unavailable with steel gaskets. \\
 +When using the MLS torque specs, you'll find they are not that different from the FSM. \\
 +For instance, after you get to 9 ft/bs, it's about a quarter turn to 14, then about a quarter turn to 22 and so forth. \\
 +But using the actual values instead of counting turns gets a more even pull on all sides and allows you to feel when something isn't right. \\
 +
 +To torque the heads, start with all four bolts loose and then snug them all by hand. Do one head at a time. \\
 +Tighten in sequence 1-2-3-4 to 9 ft/lbs. Then do the entire sequence again to 14 ft/lbs and so on until you reach full torque.
 +Pay attention to how the bolts pull. They should not spring back when you let go after turning them. \\
 +That would mean your bolts are stretching and would need to be replaced. \\
 +That would also mean they loosened after you thought you had them to the right torque value. \\
 +Do not use oil in the cap nuts (only a very light '​touch'​ on the bolt threads for smooth mesh of the mating threads. \\
 +Using too much oil on the studs or cap nuts can hydrolock the nuts and you'll never get the proper torque. \\
 +Hydrolock of the nuts stops the nut from turning on the stud threads and the only thing the stud can do when torqued from there is stretch (twist). \\
  
 ====== Valves ====== ====== Valves ======