Official Cummins QSC-500 Thread

Discussion in 'Diesel Engines/Drives/Transmissions/Props' started by Hampton, Nov 16, 2011.

  1. importmonkey

    importmonkey Opinionated Member

    940
    Jul 9, 2015
    Middle River, MD
    2007 44 Sundancer
    QSC 500s
    Glad you said this. I just noticed and thought something was going wrong. Hitting all my numbers though, so I wasn't too concerned.
     
  2. Hampton

    Hampton Air Defense Dept TECHNICAL Contributor

    Nov 26, 2006
    Panama City, Fl
    2008 44 Sedan Bridge
    Cummins QSC-500's
    Straight Drives

    It's the little thinks that either keep us awake at night or help us sleep.
     
    importmonkey likes this.
  3. bbwhitejr

    bbwhitejr Well-Known Member SILVER Sponsor

    Apr 14, 2013
    Lake Lanier GA
    2007 44DB
    Cummins QSC 8.3s
    I am getting my annual maintenance items together and found the first post of this thread to be immensely helpful and is keeping me from "reinventing the wheel." I do have one question about the zincs. The thread sizes posted there do not seem to agree with the chart at BoatZincs.com. I will not use zinc as I am in fresh water, but want to ensure I order the correct size.

    Are these the correct pencil anodes for the engines indicated by the red arrows?

    upload_2018-1-27_13-16-6.png

    Thanks,
    Bennett
     
  4. BlueYonder

    BlueYonder Member

    127
    Jan 12, 2015
    Chesapeake Bay
    37
    QSC 8.3 600
    I use four E-2 2" long zincs in my aftercooler and heat exchanger. I use 2 E-1G 1" long zincs in my Fuel/Transmission cooler.
     
  5. Magic34

    Magic34 Member SILVER Sponsor

    147
    Jul 7, 2015
    Live in AZ, Boat in San Diego
    Former 44 Sundancer Owner
    Currently Self Powered
    I can’t seem to find the oil capacity of the generator anywhere. Can someone help?
    Also, do I use the same oil as the boat motors?
     
  6. Jaybeaux

    Jaybeaux Active Member SILVER Sponsor

    332
    Jan 3, 2016
    Upper Potomac River
    420 Sundancer 2004
    Naught On Call
    Cummins 6CTA-8.3's with V-Drives
    9KW Onan Genset
    On my Onan 9 KW generator, I budget 1 gallon of oil. Of course, checking dipstick for final volume. I use the same oil as the engines: 15W40 Shell Rotella T4. Buy at Wal Mart.
     
  7. bajturner

    bajturner Member GOLD Sponsor

    531
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Highfield CL290 RIB w/ Tohatsu 9.8
    Twin QSC-500 HO
    Ok gang,
    I am still learning here and figuring out what is important, what is wrong, how to fix, etc!

    Here's one for you:
    - first run of the season after marina did spring commissioning.
    - same fuel from the fall...marina looked after winterizing.
    - boat ran perfectly when I brought it up from Boston last fall
    - had new filters installed before leaving Boston
    - marina did a quick sea trial earlier this week and didn't report anything remarkable.
    - I just did my first run this spring and noted a few things
    - port engine started a little rough with a fair bit of black smoke (no black smoke from either engine last fall)
    - some black smoke from port engine on throttle-up
    - showing higher boost than starboard (and 14psi at idle, while the starboard is at 0).
    - port reaches 100% load at ~65% throttle while starboard is at ~75% load at the same throttle setting.

    Could that be old fuel or filter related?
    What else should I be considering.

    Thanks!
     
    Last edited: Jun 8, 2018
  8. BlueYonder

    BlueYonder Member

    127
    Jan 12, 2015
    Chesapeake Bay
    37
    QSC 8.3 600
    What is your fuel flow and Rpm at full throttle?
     
  9. swaterhouse

    swaterhouse Active Member

    386
    Jan 7, 2015
    Mattapoisett, MA
    2007 Sundancer 44
    Cummins QSC 8.3
    Definitely not right, with a QSC you should never see smoke. Black smoke is too much fuel or too high load. You could have a stuck injector. I would have a Cummins tech get a computer diagnosis before running any further. Did you notice if your oil level went up at all after that first run?
     
  10. bajturner

    bajturner Member GOLD Sponsor

    531
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Highfield CL290 RIB w/ Tohatsu 9.8
    Twin QSC-500 HO
    Thanks for the replies, guys!

    BlueYonder: I did not run up to WOT, but power seemed normal. I am anchored for the weekend but will check fuel flow at wide open on the way home tomorrow.

    swaterhouse: I did not check the oil level before I left. Perhaps a bad practice, but my marina just launched and commissioned the boat the day prior so I presumed the oil level was ok. I will check and compare on my return run.

    Can I do any damage if there is a stuck injector?
     
  11. bajturner

    bajturner Member GOLD Sponsor

    531
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Highfield CL290 RIB w/ Tohatsu 9.8
    Twin QSC-500 HO
    So another day, and a different story. We decided to head back to the marina last evening since we needed to be home early this morning.

    Started the port engine. No issue, no smoke, boost normal. I thought great, problem is gone. Started starboard. All good. Let them warm-up, left the dock, and idled out. Everything looks good. Tried to give some throttle...not so good.

    Starboard spooled-up. Port wouldn't. Hesitated, surged, sputtered. I shut it down and came in on one engine...in the dark as it turned out, since it took longer than planned to get there.

    Once tied-up I started both with no issues.

    Racors look clean. Nothing unusual about the oil, that I can tell.

    We are still running on last year's fuel...about a third of a tank each side. I haven't filled-up yet as our marina, which has gas only, is arranging a fill-up for us. I am confirming what additives and stabilizers the marina used in the fall.

    These engines ran flawlessly for over a week between Plymouth, MA and our marina on Big Rideau Lake in Ontario last September. Never missed a beat. Diesel inspection was perfect.

    I am really hoping this is just a fuel issue. Is there anything else obvious that could be causing the problem?
     
  12. BlueYonder

    BlueYonder Member

    127
    Jan 12, 2015
    Chesapeake Bay
    37
    QSC 8.3 600
    Did you by any chance have the props worked on over the winter?
     
  13. bajturner

    bajturner Member GOLD Sponsor

    531
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Highfield CL290 RIB w/ Tohatsu 9.8
    Twin QSC-500 HO
    Hey BlueYonder,
    I did, actually. Apparently only a clean-up and light tune for balance was required.

    I did consider the possibility of being over-propped, but the engine is running rough and is unable to gain revolutions even while in neutral.

    I think it's safe to eliminate that variable...
     
  14. Art

    Art Member

    309
    Oct 25, 2010
    Boca Raton, Fl
    2003 450 Express Bridge
    Cummins 480CE
    Are you getting enough air? Anything blocking ER vents? Might try spooling up engines with ER hatch open.
     
  15. Alex F

    Alex F Well-Known Member

    Nov 14, 2006
    East Coast
    2005 420DB with AB 11 DLX Tender, Raymarine Dual E120 MFD/Radar/XMWeather, ST7001 A/P, AIS, SeaLift
    T-Cummins 450Cs Straight-Drives, 9KW Onan Generator, 40HP Yamaha for tender.
    If the air was an issue, I'd imagine it would impact both engines, unless the air starvation is at the airsep filter side of the bad engine.

    What I would do:
    Forget the props and entire running gear. Do no load test.
    1. Change Racors and secondary filter on the bad side.
    2. At the dock, warm up the engine and do take some readings by applying the throttle in increments (e.g. 1000, hold for 15-20 sec, 1500, hold it there, 2000......hold for 15-20 sec, then shoot to 2500 for the same 15-20 seconds........finally push to the end just to to see the WOT RPMs to take note and pull back right away).

    As I recall, no load WOT is 3000RPMs. If you don't see it, the problem is on the engine side.

    3. If the no load test was a success, it's time to take if for a sea trial and do the same with the load now.

    Disclaimer:
    If there's something more to the problem that we're aware of, WOT test even with no load is probably a bad idea. I would only do it if all other numbers and indicators were positive and the engine sounds fine at lower RPMs. If you're not comfortable, perhaps placing a call to Cummins tech is a good idea.

    The idea is to do slow and gradual acceleration with new filters and no load. If anything doesn't sound right at any point in time, back off to idle, take note of the symptoms and it's a new discovery phase at that point.

    BTW, there's a lot we don't know here. A black smoke could be that you pushed the throttles too fast too far. But, I'm just guessing here...
     
  16. Tman

    Tman Member

    284
    Aug 10, 2012
    Seattle, WA
    2014 Sabre 48 Salon Express
    Twin Cummins QSC 550
    Zeus Pod Drives
    I would also take a look at your turbo on the air side (compressor) and then take a look the air side on your aftercooler. Possible something is amiss there and your aftercooler air side is "gunked up" with oil inhibiting air flow to the engine which it of course needs as you try to throttle up.
     
  17. bajturner

    bajturner Member GOLD Sponsor

    531
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Highfield CL290 RIB w/ Tohatsu 9.8
    Twin QSC-500 HO
    Good advice.

    Here's the plan:
    1) Send Frank Webster's diesel management doc to marina - Done (PDF version attached in case it is useful to anyone).
    2) Get a complete picture of what was done to the fuel system last fall and this spring.
    3) Take any necessary actions per Frank's doc.
    4) Change all fuel filters (both main engines and generator) regardless.
    5) Check turbo air intake.
    6) Start her up and see what happens.

    For my own education...
    - I am assuming looking at the air side of the turbo means removing the air filter. Is this correct?
    - I don't yet understand all the terminology surrounding these engines, and what the general flow of air, fuel, and exhaust is. Which is the air side of the aftercooler... is it the right side in the picture below where the core is being removed, or the opposite end? More involved inspection... I will need gaskets, o-rings etc., if I am understanding correctly.

    [​IMG]

    - Racor filter element replacement: I think I am comfortable with the general procedure from reading about it on this side (this thread and/or the 44DB thread). I thought I saw essentially a step-by-step tutorial but can't find it now. Can anyone point me to one on CSR?

    Thank you again for all the help and advice. I will get up to speed on this beasts, but they are a bit daunting to me at the moment!
     

    Attached Files:

  18. Tman

    Tman Member

    284
    Aug 10, 2012
    Seattle, WA
    2014 Sabre 48 Salon Express
    Twin Cummins QSC 550
    Zeus Pod Drives
    See attached pic. Not the greatest of artwork but in the photo on the right, that is hot turbo air entering the aftercooler to be cooled. That surface of the aftercooler can become saturated with oil/water vapor and collect over time, greatly reducing the ability of the aftercooler to cool the turbo air or even inhibit airflow altogether. To see the airside of the turbo, you are correct that you remove the air filter. To see the inlet air side of the aftercooler; can either get a scope or remove the inlet air hose/pipe.
     

    Attached Files:

  19. bajturner

    bajturner Member GOLD Sponsor

    531
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Highfield CL290 RIB w/ Tohatsu 9.8
    Twin QSC-500 HO
    Thank you!
     
  20. bajturner

    bajturner Member GOLD Sponsor

    531
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Highfield CL290 RIB w/ Tohatsu 9.8
    Twin QSC-500 HO
    There is actually a pretty good set of instructions in the user manual. Relevant pages extracted and attached here. If anyone has any real-world modifications to this procedure, I would be interested in hearing your recommendations.
     

    Attached Files:

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