Need help troubleshooting rebuilt Velvet drive

Discussion in 'Inboards' started by mongo75, Nov 10, 2009.

  1. mongo75
    Joined: Aug 2007
    Posts: 262
    Likes: 6, Points: 0, Legacy Rep: 95
    Location: Orange County California

    mongo75 Senior Member

    I just rebuilt my 72c, using the book. I am extremely confident of my skills, so with that out of the way, the damn thing won't spin! My engine in a Chrysler 440, reverse rotation (looking at the crank dampner, it spins right, or clockwise) so I installed the pump with the little arrow pointing right, it turned about 2-3 rpms, so flipped the pump, no movement at all then. I don't know what the hell I could be missing here- how can I tell if the pump needs to be replaced? It's got all new seals and clutches, but I have a feeling the pump isn't pumping. Please help!

    Thanks,
    Dan
    mongo75@aol.com
     
  2. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    The manual has the troubleshooting instructions for that. You need a pressure gauge with at least 400PSI capability and you connect it to on of the two taps on top. The manual shows you where. If the flywheel spins clockwise it is reverse rotation.
     
  3. mongo75
    Joined: Aug 2007
    Posts: 262
    Likes: 6, Points: 0, Legacy Rep: 95
    Location: Orange County California

    mongo75 Senior Member

    I went through the troubleshooting steps, but I don't want to just throw money at it till I replace the right part (it may not even need a new part). And I hate this damn rotation confusing thing..... I even read about it again for like the 10th time, and yes, according to the info, I have a standard engine. I guess it's because of the velvet drive that most inboards run a rh prop with a lh engine???
     
  4. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Yes. To test the pump check the pressure at the check points. If it is good at idle and drops when you go in gear, there is an internal leak. Also, is your shift valve clear?
     
  5. mongo75
    Joined: Aug 2007
    Posts: 262
    Likes: 6, Points: 0, Legacy Rep: 95
    Location: Orange County California

    mongo75 Senior Member

    Last night I took it apart, found out that I had the drive clutch plates in the worng order, so I flipped them, got the clutch spring on the right way, and put the damn pump on with the arrow pointing the same way as the crank rotation, and put a pressure gauge on the point indicated in the manual, at the top forward section of the case. Optimistically started the engine, and NOTHING. The pressure gauge read ZERO, so I took it off, and put my finger on the hole. It felt like a pulsing, suction, pressure, suction, pressure, or it could just be pulses of suction. I think I might swap the pump one more time, but if that doesn't work, I don't know what to do. Is there a proceedure for priming the pump?
     
  6. gonzo
    Joined: Aug 2002
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    Likes: 1,714, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    It is self priming. The level of oil should be enough to get it pumping. At least now you narrowed the problem Even a worn out pump will produce some pressure.
     
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  7. mongo75
    Joined: Aug 2007
    Posts: 262
    Likes: 6, Points: 0, Legacy Rep: 95
    Location: Orange County California

    mongo75 Senior Member

    So I'll flip the pump, and see what happens..... :(
     
  8. mongo75
    Joined: Aug 2007
    Posts: 262
    Likes: 6, Points: 0, Legacy Rep: 95
    Location: Orange County California

    mongo75 Senior Member

    OK, well I got to wondering WHY whenever I put the tranny back on, that I ALWAYS manage to get it to mesh with the flewplate on the first try??? SO, I lift up the inpsection flap on the bellhousing, put the tranny on, and lo and behold, the damn input shaft doesn't go it!! I figured out that I put the flexplate on BACKWARD like a *******.... either way, I'm glad I had these problems because I found that while dissassembling the velvet drive that I musta had too many beers while putting it back together and had some stuff in the wrong way. So long story short, it works like a champ now! Thanks for the help!
     
  9. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    You're not the first one to do that. Now go boating.
     
  10. baeckmo
    Joined: Jun 2009
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    Location: Sweden

    baeckmo Hydrodynamics

    Thanks for sharing that experience (and for beeing honest......), I was really wondering about your tranny!
     
  11. mongo75
    Joined: Aug 2007
    Posts: 262
    Likes: 6, Points: 0, Legacy Rep: 95
    Location: Orange County California

    mongo75 Senior Member

    No problem, I figured my experience may be able to help someone else NOT to make the same mistake!
     

  12. gonzo
    Joined: Aug 2002
    Posts: 16,790
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    Location: Milwaukee, WI

    gonzo Senior Member

    If you start calling drinking beer a mistake, you and I will have a problem
     
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