should you be able to turn jet unit by hand

Discussion in 'Jet Drives' started by jarredpeter, Oct 21, 2012.

  1. jarredpeter
    Joined: Oct 2012
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    Location: adelaide

    jarredpeter Junior Member

    i have a hamilton jet stage 1. when the motor is un bolted the engines rev range is up to 5000rpm and when it is bolted on it only just reaches 3000rpm.

    i have notice the jet is very hard to turn only can turn it with a screw driver.

    also took it for a run the other day i was sitting on 3000rpm and was only moving 15kms an hour according to my gps what could be wrong? need help any ideas would be great.
     
  2. Frosty

    Frosty Previous Member

    Yes you should be able to turn by hand ,. What engine is it . how big is the boat. has it just started this . have you just bought it like this???
     
  3. Submarine Tom

    Submarine Tom Previous Member

    Yes, you should be able to turn it by hand.
     
  4. jarredpeter
    Joined: Oct 2012
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    Location: adelaide

    jarredpeter Junior Member

    the engine is a 186 red motor just been reconditioned so i don't think it a motor problem. the boat size is around 16 foot fibre glass hull. have own the boat for a round three years and never had this issue before. it was reaching top spped of 46 kms per hour be for this issue.
     
  5. WestVanHan
    Joined: Aug 2009
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    Location: Vancouver

    WestVanHan Not a Senior Member

    Barnacles or something else jammed in there.
     
  6. whitepointer23

    whitepointer23 Previous Member

    what you feel when turning the shaft is probably the pressure from the gland packing, it may be a bit tight, if its bearings you will hear it. i would be looking inside to see if there is a foreign object stuck in there as suggested above. it won't need much to slow your boat down. a 186 is marginal in your boat, they were pretty slow with a shaft drive let alone turning a jet. thats not to say they don't work, but they are at the lower end of the scale for a jet.
     
  7. jarredpeter
    Joined: Oct 2012
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    Location: adelaide

    jarredpeter Junior Member

    thanks guys for all your help. i found the problem pulled the jet unit off and look at the bearings there all torn up. should be all fixed for next weeks adventures. cheers
     
  8. whitepointer23

    whitepointer23 Previous Member

    glad you found the problem, you should have been able to hear buggered bearings. check the impellor it may be damaged.
     
  9. jarredpeter
    Joined: Oct 2012
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    Location: adelaide

    jarredpeter Junior Member

    check the impellor seems all good it scrapes a little on the side of the unit is that ok.
     
  10. jarredpeter
    Joined: Oct 2012
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    Location: adelaide

    jarredpeter Junior Member

    Found the problem the rear bearing was torn to shreds so all fixed. Got to ask though is it ok that the propellor is rubbing is that going effect the power, if so how would I go about fixing this
     

  11. mohawk
    Joined: Jun 2011
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    Location: New Zealand

    mohawk Junior Member

    Should be fine if it turns . its normal for the housings and wear rings to be a little out of round and a quick run will sort it out.
    When we rebuild blades it's common to have to drown the unit in wd40 or even loosen the bolts holding it together to get it running for a few seconds before head out.
     
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