83 Flht knocking

Discussion in 'Transmission' started by gigantor985, Jan 19, 2010.

  1. gigantor985

    gigantor985 Member

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    I have an old shovelhead that has a persistant knock that never seems to change or go away at any engine speed whether it's moving or stitting. I am wondering if this could be a problem with the compensator or something else and are there any easy ways to check the compensator before I just throw parts at it? I have already replaced some collapsed lifters and had the top end apart and everything checks out there. Any advice would be appreciated. Thanks
     
  2. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    First, check the easy stuff. Make sure you don't have anything loose that is just knocking against something else. When the bike is cold, or just warm, grab hold of stuff and man-handle it to see if anything is loose and makes the noise you hear. Grab the front brake and try rocking the bike forward and backwards roughly to really compress and release the front forks. Anything? If not:

    Two thinks I would worry about. First and easiest (aside from the above) is to open up the primary cover and check the compensator. Make sure the compensator bolt is tight! Also make sure the chain is adjusted.

    If not all that, then I am worried about the connecting rods. Get a stethoscope or a long handled screwdriver and start trying to isolate where the sound comes from. If you hear it on both sides of the engine and from the front and bottom (although some will be fainter), that is what I would be worrying about. Find someone with a bunch of experience to help on this to verify the diagnosis before you start stripping off the top end.

    Good luck.

    TQ
     
  3. gigantor985

    gigantor985 Member

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    It's definately an engine noise I have listened to it a few times now and it's definately coming From the lower end somewhere. I was really just wondering if there's a way to check out the compensator (which I kinda suspect that it might be) since the bike has 63000 miles on it.
     
  4. Chopper

    Chopper Senior Member

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    If you pull the inspection cover off to check the primary chain, I would take the spark plugs out and have someone crank the engine over while you listen at the inspection hole (be carefull). If you pull the outter primary cover off to check the compensator nut torque, with the spark plugs out put a socket with 1/2 inch breaker bar or rachet on the compensator nut and move the drive back and fourth, you might be able to identify where the sound is coming from better? good luck.
     
  5. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

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    Not much to it. See here:

    CHAINS AND SPROCKETS - 1983 Harley Davidson FLT


    If the spring is broken, it might give you a knocking sound, but what I have seen is the compensator nut (Sprocket Nut, #135) get loose. This is bad. But it is easy to check. On my bikes, that is supposed to be torqued to 150 or 165 ft-lbs. or something like that (away from my manuals). But I think they (HD) now recommend a new tightening procedure, but I am not sure what years that covers (just checked, and it is: All 2003 through 2005 Touring, Softail, and Dyna model motorcycles including CVO models with Twin-Cam engines. Production vehicles began using this procedure May, 2005). Anyway, if your compensator nut is tight, and the sound does not isolate to right there at the front of the primary, I would be worried about what I wrote about above.

    TQ
     
  6. maine-e-axe

    maine-e-axe Junior Member

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    Another thing to chech is the header pipe hitting the floorboard mount, it's pretty loud:small3d023:
     
  7. gigantor985

    gigantor985 Member

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    Thanks for the advice Tq, Axe, and Chopper. I did some more poking around on the bike yesterday checked the primary chain and compensator and everything was good there. So I took my stethoscope and Listened to to the engine and tracked the noise down to the crankcase it seems to be the loudest right between the the cylinders so it looks like I'm going to have to get into the engine case and check the rod bearings.
     
  8. CalgaryBikeBum

    CalgaryBikeBum Active Member

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    Sorry. I know this was an old post but...did you find what the problem was? Thanks:D