is my engine is mounted too high?

Discussion in 'Powerboats' started by the brain, Oct 6, 2016.

  1. ondarvr
    Joined: Dec 2005
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    Location: Monroe WA

    ondarvr Senior Member


    You may have misunderstood my post, and possibly the OP’s, but it’s a bit difficult to understand exactly what he’s saying.

    Just switching to SS doesn’t mean you get better performance, you need to dial in the prop get that performance gain, which may mean using several different SS props with different designs to see which works best, and the gain is frequently not huge. So if a boat/motor combo has the correct aluminum prop already, just switching to a similar SS prop may yield no gain, or maybe even result in a loss in performance. In this case it appears he has the wrong SS prop on the boat, at least for the way it’s currently set up, so using the correct aluminum prop would possibly (most likely) yield better performance than the current SS model. I didn't intend to say that an aluminum prop is as good, or better than SS, only that the correct aluminum prop is better than the wrong SS prop.

    I don’t think he meant that he over trimmed it, just that trimming it up increased RPMs, he didn’t say whether the increase in RPM’s resulted in a higher top speed though. He also asked if continuing to trim it up would cause it to lose its bite and over rev.
     
  2. the brain
    Joined: Sep 2016
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    Location: AL

    the brain Senior Member

    I was hopping to make another video w/ the new aluimin prop. w/ the speed from the GPS.

    I did't want to chance The engine overheating so I paid a boat mechanic $200. to install a waterpump impeller and lower seals (remember I was getting oil in theLU oil).

    I usalley ask for the worn replaced parts, when I picked up the boat he had a impeller I’m not sure if it even came from my engine, he claimed the old seals where all dented up I still would have liked to see what goe’s in my engine.

    I checked the oil he put in from the top oil plug none came out, then checked the lower hole oil came out seamed kindof thin though didn't appear to be 90 weight.

    Anyway after my first boat ride last week I still have water in the LU oil after first trip out.

    Now wensday 11-23-16 he won’t answer the phone I really wanted to go boating today (last kindof warm day) and run the engine dry of fuel can I still do this w/ water in oil?
     
  3. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    Obviously water in the gearbox is a problem that needs to be fixed, there are a few places it can get in, but the best way to test that is by (a little) air pressure, after draining the oil, if it can't hold a small overpressure, you can then see where the leak is by bubbles coming out when it is held underwater. Can be the input shaft, output shaft, bearing carrier in the bore, shift rod, fill and drain plugs. Gearcase oil can seem cloudy immediately after an engine is run (aeration), water will keep it looking milky.
     
  4. the brain
    Joined: Sep 2016
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    the brain Senior Member

    yes I am very disappointed in still having water intrusion in lower unit gear case after paying $200. to a so called expert mechanic.

    I actually attempted the prop shaft seals install myself I carefulley removed the LU bearing carrier I had the LU in a vice and went to find a seal pry puller type tool before I came back my friend decided to hammer out the seals gauwging up the carrier w/ his homemade tool.

    I thought I would have to replace the carrier didn't think fuild would ever stay inside/outside.

    the mechanic said the carrier could be repaired w/ JB cold weld expoxy to fill the scartchs then hone the cylinder however this mechanic decided to take a short cut and just smear permatext bearing sealer.

    when I came to pick up the boat my new prop wouldn't fit I could only get the prop. nut to go on half a turn, the mechanic comes outs and forces the nut tight pushing the prop. on all I can think of is when he installed the two prop seals he didn't press then in far enough and when he forced the prop on the glue inbetween the housing and seals where dislodged.

    today being Friday he still won't answer the phone.

    attach image of ruined carrier bearing housing.
     

    Attached Files:

  5. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Sounds like butchery !
     
  6. the brain
    Joined: Sep 2016
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    Location: AL

    the brain Senior Member

    yes the cylinder is scarthed maybe a 1/16" in a couple places, should I be looking for a replacement bearing carrier ?
     

  7. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    Should not be necessary to replace that bearing carrier, you should be able to repair any scratches as you mentioned earlier. However, the water intrusion may be coming from elsewhere, even the other end of the bearing carrier, where the ring seal fits against the bore of the gearcase, there are a number of places it can get in.
     
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