Prop shaft seal

Discussion in 'DIY Marinizing' started by Rangerspeedboat, Jul 27, 2011.

  1. Rangerspeedboat
    Joined: Apr 2009
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    Location: Texas

    Rangerspeedboat Senior Member

    Where can I get a shaft seal for a 1/2" shaft? I'm working on an inboard canoe with a Briggs 6.5 horizontal shaft. I would prefer something that doesn't leak or drip. The one of the things I considered was an old automotive water pump.
     
  2. tom kane
    Joined: Nov 2003
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    Location: Hamilton.New Zealand.

    tom kane Senior Member

    It would appear that you could have your seal above water level which is a sensible idea and it will not leak.Perhaps usual plumming fittings and a hemp seal would be good.
    The rubber hose in the image could be longer up the shaft.
     

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  3. CDK
    Joined: Aug 2007
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    CDK retired engineer

    There are plenty solutions possible. Tom Kane's stuffing box is one of them, but you could also buy a neoprene seal (simmer ring) or the ceramic seal for a garden water pump with 1/2" shaft.
     
  4. MikeJohns
    Joined: Aug 2004
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    MikeJohns Senior Member

    Yes seals are quite common around here on small runabouts with inboards. It's easy to get a springless lipped neoprene seal to suit any shaft diameter. The seal housing is often made with glass woven cloth and epoxy wrapped around the shaft tube end and the seal outer edge. Make sure it retains the seal ( wraps around over the outer face a few mm).
     
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  5. anthony goodson
    Joined: Mar 2007
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    anthony goodson Senior Member

    A piece of rubber hose with a couple of automotive grease/oil seals works well.Stainless steel hose clips hold both in place .and stainless steel seal springs ensure long life.Fill the gap between the seals with grease.
     
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  6. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Any grease that can leak into the water is a violation of the Law.
     
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  7. Landlubber
    Joined: Jun 2007
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    Location: Brisbane

    Landlubber Senior Member

    ..if you use typical shaft seals to do the job (and they will be quite OK for occasional use anyhow), simply remove the metal spring and replace with an O ring, I have done this many times and it works perfect.
     
  8. Frosty

    Frosty Previous Member

    Ha when you have a steel boat the only way to protect the inside of the log shaft is to pump it full of grease till the water behind turns blue.

    Dont even need a seal with 4 foot of shaft in grease.
     
  9. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    It may be allowed in your part of the world. However, it is a violation of national and international law.
     
  10. Frosty

    Frosty Previous Member

    While it is international law, the fishermen want to come into the marina to catch fish, they say there is better fishing. Never understood that will all the oil and antifouling around, and the mussels that grow off the pilings are delicious.
     
  11. gonzo
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    Location: Milwaukee, WI

    gonzo Senior Member

    There's also good fishing at the sewage drain.
     
  12. Frosty

    Frosty Previous Member

    Thats true, maybe we got this wrong and fish like a bit of pollution, has anyone asked them.
     
  13. Rangerspeedboat
    Joined: Apr 2009
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    Rangerspeedboat Senior Member

    Project is on hold for now, I found a different use for the motor. However my plan for a prop shaft seal is 2 sealed ball bearings inside a stainless steel tube, a thrust bearing incorporated inside the SS tube, with rubber oil seals at the end of the tube. I'll fill the tube with gear oil or grease to keep the bearings lubricated.

    Oil not allowed in water? 2 Stroke outboards???????
     
  14. CDK
    Joined: Aug 2007
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    CDK retired engineer

    Think about it some more. Sealed ball bearings are lubricated for life, oil or grease in the tube will never reach them, nor will it reach the rubber oil seals at the end. The outside one will survive because the water film protects it, the inside one will wear very quickly.
    Also try to figure out how to fill the tube with oil and how to keep the thrust bearing in place.
     

  15. pistnbroke
    Joined: Jan 2009
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    Location: Noosa.Australia where god kissed the earth.

    pistnbroke I try

    A four foot tube full of grease will absorb loads of power..a standard lip seal kept lubricated has been fine for me on the long tails.and its at the wet end ....your shaft must be well polished . lube the seal in gearbox seal which expands the seal and is a fantastic lub. A sealed bearing is to stop the grease comming out the bearing ..???
     
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