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techtalk:ih:engmech03 [2019/06/12 03:10]
hippysmack [76 and earlier models]
techtalk:ih:engmech03 [2019/12/09 16:30]
hippysmack [Aftermarket Head Gaskets]
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 |{{:​techtalk:​ih:​engmech:​1969_heads_by_monte03.jpg?​direct&​400|}}| |{{:​techtalk:​ih:​engmech:​1969_heads_by_monte03.jpg?​direct&​400|}}|
 |  1969 Iron Heads ((photo by Monte03 of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=166440&​page=6)) ​ | |  1969 Iron Heads ((photo by Monte03 of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=166440&​page=6)) ​ |
 +
 +===== 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 ======
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 ==== 79-85 models ==== ==== 79-85 models ====
 Check rods for up and down play in lower bearings. ((1979-1985 HD FSM (99484-85) pg 3-25)) \\ Check rods for up and down play in lower bearings. ((1979-1985 HD FSM (99484-85) pg 3-25)) \\
 +Measuring side shake is no longer recommended in the FSM as in above. \\
 When up and down play is detected, the lower bearing should be refitted. \\ When up and down play is detected, the lower bearing should be refitted. \\
  
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