COMPRESSION TEST.... Should i still buy it?

Discussion in 'Sport Cruisers' started by DjNiki4, May 14, 2019.

  1. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    UGH >...< Need some education guys. . .

    2004 300 Sundancer

    2 x 350 MAGs
    Port hours 262 Starboard hours 265

    So the Sea trial went okay but we did find few issues with this boat. . .

    COMPRESSION:
    The engine compression testing proved to be within the manufacturers specifications. Note: There is one cylinder on the starboard engine that is lower in compression and is of concern. It is recommended to the run the vessel, re do the compression testing. Monitor and remedy as necessary.

    Port:
    185 175
    180 180
    175 190
    175 190

    Starboard:
    195 200
    165 185
    190 190
    200 200

    SEA TRIAL:
    The sea trial proved the engines ran well at idle, the transmissions functioned properly and the trim tabs were operable. The manufacturers specifications on maximum RPM's at wide open throttle is 4600-5000. The Port engine reached 4200 while the starboard engine reached 4800 RPM's. The oil pressure appeared normal, the engine temperature appeared normal the charging systems appeared to be operable. The back down test was satisfactory.

    The port engine did not achieve the manufacturers recommended WOT RPM's.

    It does have few other tings to be repaired
    1. The starboard outdrives bellows are cracked and worn.
    2. The port outdrives cable bellows is not properly clamped.
    3. The air conditioning filter and unit is dirty.
    4. The fresh water pump cycles intermittently. Indication of a possible leak
    5. Port fuel gauge is inoperable.
    The boat is very well priced, owner lowered it down by a lot after the sea trial, ill just say its way below $35,000 but over $30,000

    I don't mind putting extra $5-$7k into it to get it running like it should... If you were me would you get this particular boat.
     

    Attached Files:

  2. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx
    502 mpi Bravo 1
    Sure, if the rest of the boat is as clean as those engines. The low rpm motor should respond well to a tune and a fuel system cleaning, the compression is there.
     
  3. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    Yes @scoflaw - rest of the boat is very clean. . front hatch has a small leak looks like it but nothing that will make me not buy the boat.
     

    Attached Files:

  4. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx
    502 mpi Bravo 1
    I'd make sure the transom assemblies don't leak. That could get very expensive.
     
  5. BillK2632

    BillK2632 Well-Known Member GOLD Sponsor

    Jun 25, 2009
    Lake Norman, NC
    1999 185 Bowrider,
    Mercruiser 4.3, Alpha I
    If that boat has been winterized and not run since last fall or longer, then an hour or two of runtime will most likely bring that cylinder up. What did the plug from that cylinder look like? When were the risers changed last (assuming this is salt water). Could be the very beginning of the riser failing. Still, based on the pictures the boat looks to be on pretty darn good condition, that one cylinder would not make me walk away -- yet. Something is keeping that motor from reaching RPMs, I would get to the bottom of it before I commit to the purchase. On the other hand, realize it is a 15yr old boat.
     
  6. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    @scoflaw Survey did not see anything wrong with that
     
  7. joeyleggz

    joeyleggz Active Member

    493
    Jan 15, 2013
    long island
    current boat: 1997 sea ray 330 express cruiser
    twin 454's efi
    Not a bad deal on a very good looking boat are the engines raw water cooled? Has it spent her life in salt water? Risers and manifolds last invoices are a must if they can’t provide that I would treat it as if you are replacing them as part of the deal
     
  8. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    @BillK2632 The Boat was winterized and it was put in the water just for the sea trial so yes last time it was ran was last season.
    The plug i am not sure the tech who performed the compression test did not say anything about the plugs
    This is a Salt Water boat and manifolds, risers and elbows were replaced in 2014. In 2017 then they did a reseal on those gaskets. engines temperature was normal under WOT as per survey.

    the motor that has the 165 psi of is the actually reaching 4800 rpm under WOT
    the other motor with all good reading is only reaching 4200 rpm under WOT so i am assuming a tune on this one should get it to 4800 rpms. l

    i asked the owner if he will let me go with him on board and perform a leak down test on that cyl hopefully is under 20 %
     
  9. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350

    Yes salt water boat in NY Long Island . . .manifolds, risers and elbows were replaced in 2014. In 2017 we then they did a reseal on those gaskets. Also in 2017 on port outdrive we replaced gimbal bearing, u-joint assembly, bellows, seals.
     
  10. bobeast

    bobeast Dance the Tide SILVER Sponsor

    Oct 22, 2017
    Isleton, CA
    2002 310DA
    350 MPI w/V-drives
    I'm not seeing anything that would cause me to run away. It has MPI so the slow engine may just need the injectors cleaned.
     
  11. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    a full tune up should take care of that issue.. however the engine with the low compression is the one who did better on the WOT test.
     
  12. techmitch

    techmitch Well-Known Member SILVER Sponsor

    May 1, 2008
    Chesapeake Bay, Middle River/Frog Mortar Creek MD.
    1999 270 DA
    Twin 4.3s W/Alpa I Gen II's
    I wouldn't write the check until you find out why that engine won't reach the WOT spec.
     
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  13. hottoddie

    hottoddie Well-Known Member

    Jan 11, 2012
    Boston/Cape Cod
    1986 Sea Ray 390 EC
    Garmin 4212 Chartplotter
    Garmin 24 HD Radar
    Garmin 546s Plotter
    454 Crusaders
    I have not seen an answer to this critical question. If raw water cooled and original 15 year old engines I myself would not buy it. Fresh water cooled engine can run almost indefinitely if properly maintained.
     
  14. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    You can tell by the engines it is raw water cooled. Fresh water cooled engines would have a tube in the front of them... why wouldn’t u buy a RWC ? My slip is in the river so it’s not as salty but I do boat in the the bay.
     
  15. sbw1

    sbw1 Well-Known Member

    Oct 10, 2006
    West Michigan
    This is listed in my signature
    This is listed in my signature
    IMG_4230.JPG I'm surprised that the engine with poor compression on the one cylinder reaches full spec while the good compression engine struggles. The RPM difference suggests a bad cylinder but the results are the opposite of what the numbers would suggest. I don't buy the idea that a boat fresh out of storage will not reach rated RPM. My boat was sea trialed right out of winter storage for a survey and ran at WOT numbers that were at spec and within 50 RPMs of each other. The buyer wondered about the significance of those numbers and the person doing the mechanical survey mentioned that a common cause of RPM differences is a weak cylinder. Of course there other causes of the differences as well.
     
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  16. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    My old 260 before tune up only did 4200 rpms after tune I was able to get 4700
     
  17. KevinC

    KevinC Well-Known Member

    Feb 25, 2011
    Long Island, NY
    2004 340 Sundancer
    1988 Proline Center Console - 90hp Mariner/Mercury
    1969 Boston Whaler
    Twin 8.1 V-drives
    Then these are probably due to be replaced if not now real soon. I would budget about $2500 for parts without labor for the two engines.

    -Kevin
     
    techmitch likes this.
  18. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    I’ve done risers before I can do it my self. But yes I am aware of it.
     
  19. scoflaw

    scoflaw Well-Known Member

    Aug 10, 2011
    cape cod mass, cape coral fl
    1999 Powerquest legend 260 sx
    502 mpi Bravo 1
    Agree with DjN, would not sweat this one bit, solid foundation with those numbers, simple fix although injectors can get pricey. I wouldn't panic on the 165 cylinder either. Motors that clean are probably just as clean on the inside as well.

    I would be more concerned with leaking transom assemblies which are difficult to spot on a sea trial.
     
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  20. DjNiki4

    DjNiki4 Member SILVER Sponsor

    172
    Sep 26, 2016
    NJ/NY/CT
    2004 260 Sundancer
    MAG 350
    I still think for the price I’m getting it and the surveyor priced it at $42000 with 5-7k into it I should be safe for few years I’m not planning on keeping it for more than 2/3 seasons ‍♂️
     

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