Official Cummins QSC-500 Thread

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

  1. Caseclosed

    Caseclosed Member

    123
    Jul 17, 2012
    SW Florida
    2007 44 Sundancer QSC 500 West marine 310 Dingy Raymarine Hybrid touch KVH
    Cummins QSC500 Vdrive
    Thanks will be doing all above recommendations.
     
  2. villain style

    villain style Well-Known Member SILVER Sponsor

    Oct 10, 2006
    Mears Point Marina Kent Island, MD
    2006 44 DA
    QSC 8.3s
    Cummins QSC 8.3s 500HO
    In my pre-purchase of my boat the Cummins tech left this note/comment. Can someone interpret for me the parts and P/N's that are being referred to?

    Air Lines: Air sep hoses are badly cracked. Boost hoses are original.

    Thanks -
     
  3. Mjresq4

    Mjresq4 New Member

    23
    Mar 8, 2016
    Rhode Island
    2006 44DA
    Cummins QSC 500
    Here is a picture of the air sep, the straight hose is Cummins pn#3971170 and the "s" shaped molded hose is #3971065. I'm not sure about the boost hose, check out Cummins Quick Serve online. Go to: parts- -air handling- -turbocharger plumbing for pics with part #'s
    Screen Shot 2019-02-20 at 12.11.02 PM.png
     
    Last edited: Feb 20, 2019
    dtfeld and villain style like this.
  4. dtfeld

    dtfeld Water Contrails

    Jun 5, 2016
    Milton, GA
    410 Sundancer
    2001
    Axiom 12 MFD
    Cat 3126 V-Drives
    I own CAT's, but similar parts on both.

    AirSep recaptures oily blow by air off the crankcase, and recycles the air/oil back into the air intake and oil sump. On my CAT's the hoses are about 2' long and I just replaced them at about $16/foot. Easy DIY job. They dont wear out very often, but can crack due to age, or in my case, become oil logged.

    The boost hose is likely a piece of hose that carries the heated and pressurized air from your turbo outlet to the after cooler. If they rupture, you don't get your turbo boost and lose power. Those also can and should be replaced. I'd have to defer to a Cummins owner to see if thats a DIY job or not.

    Here's the Walker Air Sep Page https://www.walkerairsep.com/product_detail.asp?id=613
     
    villain style likes this.
  5. z28jimi

    z28jimi Member

    66
    Feb 10, 2017
    Daytona Beach
    2006 44' Sea Ray Sedan Bridge, Highfield dinghy, 2006 22' Pathfinder
    Cummins
    Have any of you 44DB owners created a fuel consumption chart? I have QSC 500's and I'm in the process, logging RPM at 100 RPM intervals, with knots and GPH at each interval. Trying to get multiple readings at each RPM level and then take an average. Slow going, and just wondered if anyone else had similar info you could share.
     
  6. swaterhouse

    swaterhouse Active Member GOLD Sponsor

    439
    Jan 7, 2015
    Mattapoisett, MA
    2007 Sundancer 44
    Cummins QSC 8.3
    I have not, I just know the couple of standard cruise RPM's we usually run based on conditions.

    Before you go too crazy have you verified you are propped correctly, so all you fuel burns are at or under the Cummins specifications? If not do that first, speeds may come down based on that.
     
  7. bajturner

    bajturner Member GOLD Sponsor

    549
    Aug 17, 2010
    Ottawa, Ontario, Canada
    2008 44 Sedan Bridge
    Avon 380DL RIB w/ Yamaha 40
    Twin QSC-500 HO
    Here are some numbers I collected last spring:

    upload_2019-4-3_11-11-13.png

    I plan to redo this when I am back on the water this spring, and add more RPM points. I did some maintenance to the fuel system mid-last summer and I believe the performance improved....
     
    Robski97 likes this.
  8. Carpediem44DB

    Carpediem44DB Active Member

    314
    Aug 18, 2015
    Sanfransico Bay area
    2006 44 DB Sedan Bridge Raymarine E120 radar chart plotter GPS autopilot
    cummins QSC 8.3 500 HD
    4ABAD5B6-FC1C-49AC-8169-E317B777472A.jpeg I have some numbers I did when I was wondering how I was propped a couple of years ago. They are hand written at the moment and begin at 1500 rpm to WOT 2680. Might help?
    Cheers
     
    Robski97 likes this.
  9. sb in gp

    sb in gp Member

    763
    Oct 10, 2006
    Grosse Pointe, MI
    44 Sedan Bridge 2006
    Cummins QSC-500
    Does anyone have a good source for o-rings? I'd like to change the o-rings when I do my impellers, and looked at pumpvendor.com and they're charging $16 for the big o-ring where the pump mates with the engine. That seems high. I'd like to stock up on all the common o-rings.

    Thanks,

    Scott
     
  10. bbwhitejr

    bbwhitejr Well-Known Member SILVER Sponsor

    Apr 14, 2013
    Lake Lanier GA
    2007 44DB
    Cummins QSC 8.3s
    Are they not just standard O-rings?

    Why can't you measure them and pick them up at NAPA or order them from Grainger?

    Bennett
     
  11. ttmott

    ttmott PhD in OCD GOLD Sponsor

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    There is viton, buna-n, silicone, natural rubber, PTFE, EPDM, neoprene, and about ten other materials and differing hardness'. Each has a specific service so unless the exact material is known it would be a crap shoot on a failure. With that said viton and silicone are the most common. O-rings from the typical big box auto parts store are minimal grade neoprene.
    [​IMG]
     
    Last edited: Apr 8, 2019
    carterchapman likes this.
  12. BlueYonder

    BlueYonder Member

    132
    Jan 12, 2015
    Chesapeake Bay
    37
    QSC 8.3 600
    The Sherwood Impellers come with O rings in the package. What impellers are you using?
     
  13. brewster16

    brewster16 Member

    350
    Aug 9, 2009
    Long Beach Island, N.J.
    '07 44 Sundancer
    Twin Cummins QSC 8.3
    Yes indeed they do come in the package. Shouldn't need to buy them if you bought a Sherwood impeller new and in the box.
     
  14. sb in gp

    sb in gp Member

    763
    Oct 10, 2006
    Grosse Pointe, MI
    44 Sedan Bridge 2006
    Cummins QSC-500
    I’m using Sherwood impellers. I am looking for the o-ring between pump body and motor and to the seawater pipes.
     
  15. Mjresq4

    Mjresq4 New Member

    23
    Mar 8, 2016
    Rhode Island
    2006 44DA
    Cummins QSC 500
    Have you tried Seaboard Marine? They have o ring kits available.

    sbmarine.com
     
  16. sb in gp

    sb in gp Member

    763
    Oct 10, 2006
    Grosse Pointe, MI
    44 Sedan Bridge 2006
    Cummins QSC-500
    Thank you. Yes, I've looked at their kits. They have a kit (#1730) with a football gasket, which is not what is originally used on my QSC-500, so I'm not sure it is correct for the pump I have, maybe someone can confirm if it will work as a replacement. I have the original pump which has an o-ring where the pump meets the engine and not a football gasket.
     
  17. swaterhouse

    swaterhouse Active Member GOLD Sponsor

    439
    Jan 7, 2015
    Mattapoisett, MA
    2007 Sundancer 44
    Cummins QSC 8.3
    I would call or email sbmar, I cannot say enough how great a resource they are.
     
  18. z28jimi

    z28jimi Member

    66
    Feb 10, 2017
    Daytona Beach
    2006 44' Sea Ray Sedan Bridge, Highfield dinghy, 2006 22' Pathfinder
    Cummins
    Thank you to bajturner and Carpediem44DB...those numbers were exactly what I was looking for and match up pretty well to what I'm finding. Nice to have confirmation.
     
    Robski97 likes this.
  19. z28jimi

    z28jimi Member

    66
    Feb 10, 2017
    Daytona Beach
    2006 44' Sea Ray Sedan Bridge, Highfield dinghy, 2006 22' Pathfinder
    Cummins
    Looking for some real-world experience here...I've pulled the aftercoolers, and one came apart OK, the other not so much. New aftercooler on the way from Seaboard. Ouch. Pondering what to do with the heat exchangers and oil/fuel coolers. I'm considering running Barnacle Buster through the system (once the aftercoolers are reinstalled obviously) but would like to hear from anyone who has done so, and from anyone else who can explain why doing so instead of taking the components off the engine would be a foolish move.
     
  20. swaterhouse

    swaterhouse Active Member GOLD Sponsor

    439
    Jan 7, 2015
    Mattapoisett, MA
    2007 Sundancer 44
    Cummins QSC 8.3
    Have either fuel/gear cooler or heat exchanger ever been done? The fuel cooler is already more than half off to get at the after cooler, and if its been more than 5 years your due for a coolant flush anyway so its not that much more work to pull them off.

    That said, I am 99% sure I was the first to do mine after 9 years and they weren't all that bad so barnacle buster may be fine for the fuel cooler and heat exchanger.

    As you discovered pulling apart the aftercooler is very important!
     

Share This Page

Show Sidebar