Page 1 of 4 123 ... LastLast
Results 1 to 10 of 37

Thread: 46 Knuckle engine

  1. #1
    Join Date
    Apr 2008
    Location
    Upper Yarra Valley, Victoria. Australia
    Posts
    829

    Default 46 Knuckle engine

    Howdy.
    46 Knuckle engine build for your entertainment.

    P8070001.jpg


    Knock, knock, anyone home? Eviction notice is served.

    Ever notice the smell that comes out of these things when the mud seal is broken. Phew!!

    P8070004.jpg

    P8070005.jpg
    Steve Little
    Upper Yarra Valley. Victoria.
    Australia.
    AMCA member 1950

  2. #2
    Join Date
    Apr 2008
    Location
    Upper Yarra Valley, Victoria. Australia
    Posts
    829

    Default

    Good condition Knuckle heads are hard to find. These were reasonable but have a few issues to work around.
    The rubber band inlet nipple was well sealed but eventually gave way with some brutish persuasion from a colet spanner.
    Threads are now, as good as new.

    P3150001.JPG

    P3150002.JPG

    P3150003.JPG

    P3150004.JPG
    Steve Little
    Upper Yarra Valley. Victoria.
    Australia.
    AMCA member 1950

  3. #3
    Join Date
    Jan 2009
    Posts
    27

    Default

    thanks in advance steve. intake came out nice.do you just hold the head on your bench and turn the tap by hand? or does it go in some kind of fixture.

  4. #4
    Join Date
    Jun 2001
    Location
    Central Illinois, USA
    Posts
    3,301

    Default

    Quote Originally Posted by Steve Little View Post
    ..Threads are now, as good as new.
    You're not out of the woods, yet, Steve!

    Note that the threads have nothing to do with sealing the nipples.
    That broken thin lip around them is supposed to bite into the shoulder of the nipple.

    Its a simple silver-solder and sculpting repair, if you've done it a few times.

    ....Cotten
    AMCA #776
    Dumpster Diver's Motto: Seek,... and Ye Shall Find!

  5. #5

    Default

    For the same reason I did not like the replacement nipples thread fit [I would think twice at least] before using a tap in that situation.....taps tend to take too much away & you end up with loose threads.A used nipple with a v filed in threads used as tap would be better in my opinion

  6. #6
    Join Date
    Jun 2001
    Location
    Central Illinois, USA
    Posts
    3,301

    Default

    Quote Originally Posted by duffeycycles View Post
    For the same reason I did not like the replacement nipples thread fit [I would think twice at least] before using a tap in that situation.....taps tend to take too much away & you end up with loose threads.A used nipple with a v filed in threads used as tap would be better in my opinion
    Sorry to repeat myself, Duffey!

    But the threads have little to do with sealing, other than holding the nipple firmly against the sealing lip.

    No straight threads seal by themselves.
    They ain't NPT...

    I agree though, a used nipple is a decent thread chaser.

    ....Cotten
    PS: I have found no evidence that H-D used a sealer, but I did for Chiefs.
    Attached Images Attached Images
    AMCA #776
    Dumpster Diver's Motto: Seek,... and Ye Shall Find!

  7. #7
    Join Date
    Apr 2008
    Location
    Upper Yarra Valley, Victoria. Australia
    Posts
    829

    Default

    Howdy fellas. Glad to see a hive of activity.

    Hi nuklhd
    I don't have a fixture. Held the head down with one hand and screwed in tap with the other. CRC lubed the process. It's a “Start” tap and has a chamfered lead. First thread measures at 1;718” diam and graduates out in size to a total of 1.756 at 1/2” out. This makes it perfect for cleaning or reshaping marred threads. I mainly use it on Pan heads because of the mess the aluminium threads can become. Using this tap and sealant has given me excellent results.

    Tom.
    You are the undisputed guru on inlet manifolds and carburetors, and you have lead the charge for giving the vintage HD world advice on sealing manifolds for many years. I appreciate your advice and agree with all that you have written, but I wont be brazing the small section of missing lip. I will coat the threads with sealant and bring the nipple up tight to the lip.

    Thanks Duffey.
    The threaded depth of both these heads is 15/32” so the chamfered section of the “Start” tap was not big enough to remove metal and just removed the goop from the thread.
    I agree with you on the Colony replacement nipple. Looks like they have added length to the threaded section for an O-ring. I will have to put the Colony nipple in the lathe and turn off 040” as it bottoms out before hitting the lip. I would prefer to tighten up to the lip for an even support rather than bottom out against the inner most thread.


    P8110001.jpg
    Steve Little
    Upper Yarra Valley. Victoria.
    Australia.
    AMCA member 1950

  8. #8
    Join Date
    Apr 2008
    Location
    Upper Yarra Valley, Victoria. Australia
    Posts
    829

    Default

    Spent the day working on rocker tins.

    P8080010.jpg

    There were a few cracks to take care of, but first I needed to press the distortion out of the bottom.
    Better to press them flat before brazing the cracks.


    P8080012.jpg


    P8080014.jpg

    The press tools do a nice job of this.

    P8080015.jpg

    The smaller mandrel fits neatly inside the base of the spring enclosure and the extension is long enough to stick out the top to press on. Buy flattening it out, I have more contact area and a better chance of the tin to seal to the gasket on the head.

    P8080016.jpg
    Steve Little
    Upper Yarra Valley. Victoria.
    Australia.
    AMCA member 1950

  9. #9
    Join Date
    Apr 2008
    Location
    Upper Yarra Valley, Victoria. Australia
    Posts
    829

    Default

    Once the bottom was made flat I could braze the cracks.

    P8080020.jpg

    P8080021.jpg
    Chipped the glass off the weld and gave it a light press to make sure it was still straight.
    Now to get the tin covers to fit nicely.
    Steve Little
    Upper Yarra Valley. Victoria.
    Australia.
    AMCA member 1950

  10. #10
    Join Date
    Apr 2008
    Location
    Upper Yarra Valley, Victoria. Australia
    Posts
    829

    Default

    These are original rocker tins and look like they have had many years of rebuilds. The lids were badly warped and had suffered mistreatment somewhere along the line.
    Some patience and a few hours of light hammer work on mandrels and they came out pretty good.
    The lids are sitting in position without screws.

    P8110004.jpg

    P8110005.jpg

    P8110006.jpg


    A picture with the screws fitted. The gaskets should seal up nicely.

    P8110001_1.jpg

    The next step will be to mock the tins on a head and bolt the alloy cover in place.
    By doing this, I will be able to check the contact area of the tins on the rubber seal in the alloy cover.

    The picture below, shows a screwdriver pointing to a common problem with Knuckle rocker tins.
    Maybe the guy who worked the incline press didn't always get the plate in the die-set quite right.
    When this bottom tin was formed to the shape, it must have been a bit skewed in the die set.
    Not much chance that the rubber gasket in the alloy cover will make a good seal against this type of misalignment.

    P8110003.jpg

    When I get the cover mocked up on the head I will be able to make a decision if I need to file some off, or add some metal by welding.
    Steve Little
    Upper Yarra Valley. Victoria.
    Australia.
    AMCA member 1950

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •