Are head and cylinder gaskets compression gaskets? |
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Are head and cylinder gaskets compression gaskets? |
stevegm |
Oct 22 2016, 01:04 PM
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#1
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Advanced Member Group: Members Posts: 2,111 Joined: 14-July 14 From: North Carolina Member No.: 17,633 Region Association: South East States |
I need to remove the heads off of a newly rebuilt engine (4-cylinder) I built (never run). They have already been torqued. Are the head gaskets and gasket between the cylinder and block, compression gaskets that should be thrown away (i.e., replaced with new one) after I untorque the heads?
The head gaskets will be easy to replace. But I'd have to pull the cylinders to replace the ones between them and the block. |
N_Jay |
Oct 28 2016, 01:10 PM
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#2
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Member Group: Members Posts: 283 Joined: 2-March 16 From: Chicago NW Burbs Member No.: 19,720 Region Association: None |
Hey! Hay!
I know all about the famous o-ring failure. (What type of seal would you have suggested? That aside, I was thinking more along the lines of a annealed aluminum or copper ring, not a silicon rubber one. All in all, just engineers daydreams. Still wonder, why the head bolt torque is not adjusted up or down based on the surface area of the cylinder to head seal? Hmmmm? Seems the clamping force in PSI is what you want to control? |
Jake Raby |
Nov 14 2016, 12:36 PM
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#3
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Hey! Hay! I know all about the famous o-ring failure. (What type of seal would you have suggested? That aside, I was thinking more along the lines of a annealed aluminum or copper ring, not a silicon rubber one. All in all, just engineers daydreams. Still wonder, why the head bolt torque is not adjusted up or down based on the surface area of the cylinder to head seal? Hmmmm? Seems the clamping force in PSI is what you want to control? Going up on head torque is the fastest way to create head leaks, with or without gaskets. Due to the non square stud pattern, and the two different lengths of head stud its pretty easy to tweak a head once its hot. |
stugray |
Nov 15 2016, 03:45 PM
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#4
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Advanced Member Group: Members Posts: 3,824 Joined: 17-September 09 From: Longmont, CO Member No.: 10,819 Region Association: None |
Hey! Hay! I know all about the famous o-ring failure. (What type of seal would you have suggested? That aside, I was thinking more along the lines of a annealed aluminum or copper ring, not a silicon rubber one. All in all, just engineers daydreams. Still wonder, why the head bolt torque is not adjusted up or down based on the surface area of the cylinder to head seal? Hmmmm? Seems the clamping force in PSI is what you want to control? Going up on head torque is the fastest way to create head leaks, with or without gaskets. Due to the non square stud pattern, and the two different lengths of head stud its pretty easy to tweak a head once its hot. So what is the consensus on retorquing the head nuts on the type-IV after X miles? IIRC for the type-I it was required. On these engines it is much more difficult with half the nuts behind the shrouds. Seems that at lest one of mine was below 18 ft-lbs when disassembling. I am fairly certain that I used exactly the specified torque of 23 ft-lbs using the proper pattern during assembly. Too bad there's no easy way to assemble the long block and put it in an oven overnight at ~280 deg F then retorque after cooling. |
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