Survey Says... Over Loaded!

Discussion in 'Diesel Engines/Drives/Transmissions/Props' started by dtfeld, Feb 3, 2018.

  1. dtfeld

    dtfeld Member

    31
    Jun 5, 2016
    Atlanta
    410 Sundancer 2001
    Cat 3126 V-Drives
    Survey completed on 2001 Sundancer w 3126's. Biggest issue is the boat is slightly over loaded or propped according to CAT Mechanic. Here is the exact verbage.

    SEA TRIALED AND TAKE RECORDINGS OF ENGINES PERFORMANCES. ON SEPERATE
    MARINE INSPECTION FORMS.
    PORT AND STAR MAIN ENGINES ARE NORMAL PRESSURES AND TEMPERATURES.
    LOAD ON PORT AND STAR MAINS CURRENTLY SLIGHTLY HIGH DUE TO ROUGH PAINT AND
    UNEVEN SURFACE ON PROPS ONLY ALLOWING ENGINES TO REACH ONLY 2700 RPMS
    INSTEAD OF REACHING RATED FULL LOAD OF 2800 RPMS.


    I'll have to get a picture of the props, but they had a heavy coating of antifouling paint with lots of chips out of paint. Props were servicable and generally in good condition, tracked pretty well, 1 blade was slightly off track o the starboard engine, port pretty good.

    Bottom was recently repainted and looked really good 9.5/10

    Boat weighed a a little over 28,000 lbs with weight of slings removed. I think about 1/2 fuel and full water 6 adults on board

    My guess these are the original props and really need to be cleaned, balanced and possibly an inch of pitch taken out.

    CAT and separate surveyor both not very concerned...

    Ready...Set...GO!

    Note: I edited the title to read overloaded, as some pointed out, that's not what the tech said. I equated overloaded to be over propped.
     
    Last edited: Feb 5, 2018
  2. dtfeld

    dtfeld Member

    31
    Jun 5, 2016
    Atlanta
    410 Sundancer 2001
    Cat 3126 V-Drives
    Prop and Rudder Prop.PNG
     
  3. northern

    northern Active Member

    Jan 17, 2007
    West coast Vancouver to Alaska
    380 Aft Cabin 1989 GPS and Charts by Nobeltec
    Twin 454 strait shaft
    I got my hull stripped to original 2 coats epoxy and repainted $7,000 US. Props cost 400 CDN last summer to clean, balance and repitch
     
  4. NotHerDecision

    NotHerDecision Active Member PLATINUM Sponsor GOLD Sponsor

    902
    Jun 28, 2016
    Houston, Texas
    2001 Sea Ray 460 Sundancer
    2014 Seadoo 155 LTD
    2105 Seadoo 130 SE
    2013 Mercury Dinghy
    Cummins 6CTA 8.3L
    It’s fairly typical to be overpropped. You should fill the bot with fuel, water, your normal load of people an then run it at WOT to get your reading before adjusting the pitch. Also keep in mind the Searay tach’s are really not that accurate so when you test make sure you read the RPM with a phototach.

    Good luck with the new boat! Nothing to fret about
     
  5. dtfeld

    dtfeld Member

    31
    Jun 5, 2016
    Atlanta
    410 Sundancer 2001
    Cat 3126 V-Drives
    Thanks NHD...the rpm's were measured using photo tach and confirmed on the dash tachs. I added up what I thought the boat weighs on excel (pretty close to 28000#) ran the prop analysis over on Boatdiesel.com the best I could and it shows the boat over propped.

    I agree that the best thing to do is load it the way I want to run the boat and then make the adjustments.

    There is a punchlist of items, but all fluid samples came back in the green, and it looks good and runs well. We'll see! Data.PNG Chart.PNG Weight-Power-Change Tables.PNG
     
  6. ZZ13

    ZZ13 Well-Known Member GOLD Sponsor

    Nov 25, 2009
    Lady's Island, SC
    2001 400 Sedan Bridge
    Cummins 450 Diamond
    Welcome to the world of Sea Ray diesel boats. Overpropped right out of the factory for all but the lightweight lake boater. It'll be one boat dollar to get them both groomed to the way they should have been delivered.

    So does this mean I am sending you that RN300?
     
    dtfeld likes this.
  7. dtfeld

    dtfeld Member

    31
    Jun 5, 2016
    Atlanta
    410 Sundancer 2001
    Cat 3126 V-Drives
    Possibly!!!!
     
  8. NorCal Boater

    NorCal Boater Well-Known Member SILVER Sponsor

    Jan 24, 2008
    Covington, LA
    Cobalt CM23
    GM SB 383" Stroker" Alpha Gen I
    So I'm curious.... What did the surveyor use for tachs for his RPM readings? If he used the tachs on the boat they could easily be off a hundred RPMs. when I was selling a 52' Motoryacht with Cat 3208s the surveyor reported to the buyers that the motors we bad as they would not reach RPMs while not under load as indicated by the Aetna digital tachs. Naturally, the buyers wanted big discounts for the bad motors. I had my own engine surveys done and my surveyor used a hand held tach that took the readings directly off the crankshaft/harmonic balancer. The motors were right on the money. The Aetnas were off more than 300 RPMs.

    From looking at the pics of the props they definitely need attention but the could be the right props.

    Shawn
     
  9. bobeast

    bobeast Dance the Tide SILVER Sponsor

    141
    Oct 22, 2017
    Isleton, CA
    2002 310DA
    350 MPI w/V-drives
    I didn't see in your posted verbiage where the surveyor said it was over-propped. I'd have my props cleaned up and then tach them with a handheld. At only 100 rpm off spec, dirty props and questionable tachs, my guess is you already have the correct props.
     
  10. dtfeld

    dtfeld Member

    31
    Jun 5, 2016
    Atlanta
    410 Sundancer 2001
    Cat 3126 V-Drives
    Cat factory tech 30 years on marine diesels. Used strobe tach and correlated to what the dash gauges were reporting. All rpms reported were off the strobe tach

    Starboard dash tach was about right, port was off and erratic. It’s on the needs work list

    Those guys Spent 6 hours pouring over, under and around those engines. I feel pretty good about the engines, my question is the paint on the props causing 100 rpm loss. I ran a prop calculator for the weight and it does in fact show the props have about an extra inch.

    I think clean them up, true em up and see what happens, secondarily, take a little pitch out, should be turning 2800.
     
  11. NotHerDecision

    NotHerDecision Active Member PLATINUM Sponsor GOLD Sponsor

    902
    Jun 28, 2016
    Houston, Texas
    2001 Sea Ray 460 Sundancer
    2014 Seadoo 155 LTD
    2105 Seadoo 130 SE
    2013 Mercury Dinghy
    Cummins 6CTA 8.3L
    My opinion on props is pretty simple. Take a little more off then you think. What’s the worst that can happen? You lose a knot or 2. Who cares we aren’t going for any speed records and your engine is happy.
     
    dtfeld likes this.
  12. ttmott

    ttmott Well-Known Member GOLD Sponsor

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    Typically most all of these boats were a bit on the aggressive side regarding propellers. On my 2000 400DA w/3116TA's I had 1.5 inch taken out of the prop's which increased the engine RPM's about 150 RPM. As a bit of advice request a "RPM change" when working with a propeller shop rather than a "pitch change".
    I'm sure you are on it but key things in the survey are:
    • Good oil samples in the engines, generator, and gears
    • Engine blow-by pressures are less than max spec.
    • Depending upon engine hours, service records for engine top end service and aftercooler service as well as generator valve adjust.
    Tom
     
    dtfeld likes this.
  13. The Bill Collector

    The Bill Collector Well-Known Member SILVER Sponsor

    Jun 2, 2008
    Tacoma, WA
    450 Sundancer
    3126 Cat's
    I have never painted my props...
     
  14. dtfeld

    dtfeld Member

    31
    Jun 5, 2016
    Atlanta
    410 Sundancer 2001
    Cat 3126 V-Drives
    All of these items checked out. Thanks everybody!
     

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