In process of purchase 2005 Sea Ray 420 Sundancer (Bad engine oil test)

Discussion in 'Newbie Lounge - NEW' started by Scott’s 420, Nov 10, 2017.

  1. peterkvs

    peterkvs Member

    Nov 11, 2012
    Guntersville, Alabama
    400 Sundancer 1999
    3116 Cats, 1000 hours
    Haha frank, I said who drives around with NEW spare hoses. I carry spare hoses but they are usually the old ones I had pulled off when putting on the new hose. Seems more practical (and potentially less costly) than driving around with old hoses on waiting for it to fail before you replace it.

  2. Woody

    Woody Well-Known Member PLATINUM Sponsor

    Nov 20, 2007
    N. Wisconsin/Lk Superior
    2005 420DA
    Cummins 6CTA8.3
    I carry 'new' hoses and belts also. If I put a new belt on I also have a new spare one. I don't want to blow a belt out on the lake and replace it with a belt that I already took off because I thought it could let me down, just going to have to put a new one on later anyway....if I ever get back to shore.:eek:
  3. boatman37

    boatman37 Well-Known Member

    Jun 6, 2015
    2006 Crownline 250CR. 5.7 Merc BIII
    Previous: 1986 Sea Ray 250 Sundancer. 260 Merc Alpha 1 Gen 1
    5.7 Merc BIII
    I left my old belts in with my other essentials when I replaced them this spring. We boat on the river so never far from shore but at least with having an extra belt we can get back to the marina. The old ones weren't 'bad', just had no idea how old they were and figured I would take preventative measures.
  4. ttmott

    ttmott MS/PhD in OCD GOLD Sponsor

    Apr 3, 2012
    Space Coast Florida
    2006 52 Sedan Bridge
    Cummins QSM11
    Here is my take on the oil. Usually piston / cylinder issues have high indications of chromium as the rings (which are very high in chromium) will degrade with issues related to pistons and cylinders. Aluminum by it's self can source from many items and in Cummins it's not uncommon from the aftercoolers if they are not properly serviced (raw water leakage into the air side). You didn't mention how many hours are on the oil unless I missed it..... Copper and sodium are key indicators to help understand the complete picture. Iron can come from many locations like condensing water on the internal surfaces of the engine block as well as frictional wear and external contamination. So it is important to know that one analysis does not make a complete picture of the situation and if you are interested in the boat have the cylinders scoped, look inside of the aftercooler, and have the oil in both engines analyzed again.
  5. Carpediem44DB

    Carpediem44DB Active Member

    Aug 18, 2015
    Sanfransico Bay area
    2006 44 DB Sedan Bridge Raymarine E120 radar chart plotter GPS autopilot
    cummins QSC 8.3 500 HD
    Lots of good comments and advice posted on this. I concur with at least having the head replaced. If it is the original it’s just a matter of time before a valve seat goes. There have been at least three revisions done to the head. Out here in CA it would cost about $6500 for replacement. I’d have both done to sleep soundly. I’d still worry about the aluminum though.
    Best of luck to you
  6. northern

    northern Well-Known Member

    Jan 17, 2007
    West coast Vancouver to Alaska
    380 Aft Cabin 1989 GPS and Charts by Nobeltec
    Twin 454 strait shaft
    Have friend with same engine he just spent 26,000 rebuilding it.
  7. JVM225

    JVM225 Well-Known Member GOLD Sponsor

    Apr 8, 2008
    Farmingdale, NY
    2002 410 Sundancer, Monaco Edition.
    3126 Cats.
    I agree. Happened to a friend with his port motor on his 05 420 Sundancer this summer. Head was original and tech called the valve seat and cylinder before even taking it apart. That’s how common the problem is.
    I think it was exhaust valve seat in cylinder 4 that let go but I remember that once it was apart there was some cracking on other valve seats too.
    He got lucky in that just the piston took a beating but the cylinder was OK.
    I think the bill for the new head, piston, miscellaneous other related parts and labor were just under 10k. That may have included him sending all the injectors out to get rebuilt while it was apart. I think he was working something out with Cummins for partial compensation for the head itself which was more than 3k, but don’t know how it all worked out.
    He (his insurance company actually)replaced the starboard motor a year earlier for an unrelated incident and that one already had the latest design head.
    BTW: I carry spare brand new belts and hoses too.

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