Torque question

Discussion in 'Dyna Models' started by R_W_B, Oct 24, 2010.

  1. R_W_B

    R_W_B Senior Member

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    I have a question about torque. I recently put the oil pressure switch back in and the manual said to tighten it 96 to 144 inch pounds. (8 to 12 ft lbs) But for leak areas I always use teflon pipe wrap (staying away from the first couple of threads in, leaving them bare). I stopped pulling at about 4 ft lbs because it just felt right to me. My question is:
    When using pipe wrap it cuts down considerably on the thread friction and allows you to more easily tighten the part. So I'm thinking don't pay much attention to torque values when using pipe wrap or you might strip something ?
    Appreciate any info.
     
  2. Jack Klarich

    Jack Klarich Expert Member

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    I would add sending switches are tapered pipe thread and with proper sealant do not have to be overly tight, I bet you could remove the original one with ease, been doing it this way for a long time with no leaks, Good Luck and happy riding Capital Jack:s
     
  3. bobwire

    bobwire Active Member

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    there shouldn't be torque values on tapered thds..................bw
     
  4. Elmosac

    Elmosac Active Member

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    I'm glad there are so many responses with engineering support for their oppinions.

    First, why would you not follow the torque specs in the manual? Are you smarter and more experianced than the engineers who specified the torque value?

    I have seen thread tape cause more problems than it has ever prevented. Pipe dope is a much better product, it not only helps to seal the threads it lubes them and helps prevent stripping the threads, something your thread tape can cause.

    US plumbing code does not allow you to use thread tape on gas lines, you are required to use pipe dope. If it is good enough for natural/propane gas lines it is good enough for me. Using pipe dope does not change the torque requirement.

    I am a jet engine mechanic and believe you me, safety is a big deal. Not following the torque specs in the manual is a life safety issue in my world.

    Why would you spend $50 for a manual that your not going to follow? If "just winging it" is good enough, I recommend you through away the manual and just go with "what feels good."

    I'd also be very leary of any suggestions that advise you to do something differant than what the manual calls for. Some time saving suggestions are O.K. but when someone tells you it is OK not to follow torque specs or that it is OK to reuse gaskets, it is your call. Just remember when your bike starts falling apart it isn't HD's fault as you chose not to follow the manual.

    I know guys who still kick the tires to check tire pressure before a ride. Personally I likel to actually use a pressure guage to see what the tire pressure in fact is.
     
  5. Hoople

    Hoople Account Removed

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    In some cases Yes!. Do you actually believe because the "factory" said so, it is 100% absolutely correct.? I can not tell you the number of times I have found the manufacture to be INcorrect. Even though they developed the product, it does Not mean an improvement or a mistake can not be found.
     
  6. whacko

    whacko Junior Member

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    Wow…..your reply is quite a bit condescending to me. If you think someone should stick to the manual you should probably just say “hey my friend I’ve been a professional mechanic for years and would recommend you stick with the manual.”

    See how much nicer that sound!!!!
     
    1 person likes this.
  7. Iceman24

    Iceman24 Well-Known Member

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    And...bikes don't fly 500+ mph @ 30,000 feet. I think the correct/better reply would be to promote pipe dope over teflon tape. I believe that was the point...
     
  8. HarryB737

    HarryB737 Junior Member

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    I too followed recommended torque settings on the muffler clamp when I upgraded to SE mufflers on the Sportster.... After the bolt broke and I had to go back the the dealer for another clamp I used what I felt like a proper tightness, and never had a problem. In your case, if the brake light pressure switch is not leaking at the threads, I would keep an eye on it for awhile and then not worry about it.
     
  9. R_W_B

    R_W_B Senior Member

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    [ Elmosac wrote : First, why would you not follow the torque specs in the manual? ]

    Well that was the question, my thoughts were since the teflon tape (or any pipe dope) lubricates the threads so as to allow easily tightening to a leak proof state, the "torque" or twisting resistance you feel would not be the same as raw metal. Which I would have to assume the torque values are based on raw metal. So you could actually tighten it past the recommended point if you kept going to the documented resistance on the wrench.
    It is not leaking and it's tight enough that I don't think it's going to vibrate loose so I figure I'm in much better shape than a stripped thread on my crankcase. I don't have them accessible right now but some Harley manuals (and printed sheets that come with parts) have different torque values for the same parts, it's rare but I have seen it. But of course that last statement is deviating a bit from the point of my question. I have done a bit of house plumbing and the whole reason for pipe dope is to make the tightening of pipe thread easier since in some tight places it can be pretty darn hard to get copper, brass or galvanized to tighten enough not to leak, it tends to bind without pipe wrap or dope and you will keep getting those slow drips without it.

    ---------------------------------------------------------------------------------------

    Oh and by the way the reason natural gas codes don't allow teflon tape is because pieces of it can clog the gas fiittings if they get loose in the pipe. I think that is to protect against sloppy work since if you leave it away from the first threads in that won't happen. But most plumbers in my area use teflon on everything but gas since it stops leaks better. I'm not a plumber, (I did work in construction most of my life) but the side plumbing I have done, I have had pipe dope keep having a slow drip leak. I would pull the joint apart clean it up and wrap it with teflon and it would not leak. But again the point is, it changes the torque resistance on the wrench.
     
    Last edited by a moderator: Oct 25, 2010
  10. Jack Klarich

    Jack Klarich Expert Member

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    The biggest problem with tapered pipe thread is it will leak without some dope on the threads, I have always used brush on teflon and never had a leak in all my years of wrenching, JMO:s