Looking for a new 351

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
  • pj
    • Oct 2003
    • 323

    • Rochester, MN

    • 1991 SN 1996 SN
    #1

    Looking for a new 351

    So, this past weekend I had a catastrophic engine failure on my 91 ski nautique. My best guess is that there is a crack in the block and one of the cylinders hydro-locked. At first I thought it was a blown head gasket. I compression tested each cylinder and found that one of them had NO compression at all. We pulled the head off of that side and there is a fairly large chunk of the piston that is missing. I'll have some pictures posted by tomorrow. The engine has 740 hours on it. It was purchased with approx 650 hours and has been winterized properly ever since I owned it (2 seasons). Not sure if anything out of the ordinary happened before that.

    So, what am I looking for? It has a carbed Ford 5.8L 351ci.
    I might be dreaming this. But, I think that the motor and the prop rotate in opposite directions. The prop is definitely RH. So, is there a reverser in the tranny and I should look for a standard rotation engine? Or, is that what they mean by a RH rotation engine?
    Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For it is there you have been and there you will long to return. - Leonardo De Vinci
    Tags: None
  • darrel409
    Senior Member of PLANETNAUTIQUE
    • Jul 2004
    • 566

    • San Dimas, So. Cal

    #2
    RE: Looking for a new 351

    Yes the 1.23 tranny reverses rotation. You have a standard rotation motor.

    Comment

    • pj
      • Oct 2003
      • 323

      • Rochester, MN

      • 1991 SN 1996 SN
      #3
      what's wrong with this picture?
      Doesn't look too good, does it?
      Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For it is there you have been and there you will long to return. - Leonardo De Vinci

      Comment

      • pj
        • Oct 2003
        • 323

        • Rochester, MN

        • 1991 SN 1996 SN
        #4
        Does anybody know if I need to get a "marine" block, or can i just swap out all the good stuff from the old motor and use a 351 block from an old truck or something?
        Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For it is there you have been and there you will long to return. - Leonardo De Vinci

        Comment

        • kelpy
          • Feb 2006
          • 11

          • SoCal

          #5
          Hydrolocking would in most cases bend the rod. Do you see any cracks in the cylinder wall. It is hard to tell in the picture.
          It appears that your engine has suffered some severe preignition (pinging) and the skirt has collapsed on that piston . This will cause the upper ring land failure pictured. Look at how much of the top piston ring is visable compared to the adjacent cylinders. The normal gap should only be around .004 - .008.
          If this is in fact the case and you caught the failure in time, a light hone in that cylinder and a new piston will get you back on the water for the summer. But since the engine has to come out anyway, you might as well do it right the first time.

          Comment

          • pj
            • Oct 2003
            • 323

            • Rochester, MN

            • 1991 SN 1996 SN
            #6
            I'm assuming we have a crack in the cylinder wall. I wasn't able to see it. But, i'm not sure how else I would have gotten so much water in the oil with the head gasket still in tact.
            Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For it is there you have been and there you will long to return. - Leonardo De Vinci

            Comment

            • surroundsound64
              1,000 Post Club Member
              • Jul 2005
              • 2147

              • Longview, TX

              • 2018 230 1981 Ski Nautique
              #7
              Originally posted by pj
              I'm assuming we have a crack in the cylinder wall. I wasn't able to see it. But, i'm not sure how else I would have gotten so much water in the oil with the head gasket still in tact.
              Just out of curiosity, what octane gas did you use?
              2018 SAN 230
              1981 Ski Nautique
              Sold - 2011 Sport 200V
              Sold - 2000 SAN

              Comment

              • kelpy
                • Feb 2006
                • 11

                • SoCal

                #8
                The clean appearance of the piston crown is a sure sign that some water got into that cylinder. The water could come from a leaking intake manifold gasket or a cracked head. Look for cracks between the spark plug hole and the exhaust valve seat. Either is much more likely than a cracked block.How much water was in the sump - how overfilled was it.
                Without seeing the engine in person though, I would lean toward piston and head gasket failure caused by detonation. Be sure to inspect all of the other pistons when you tear her down if you plan to reuse them.

                Comment

                • wake_fun
                  1,000 Post Club Member
                  • Jul 2003
                  • 1330

                  • CA

                  • 1995 Super Sport
                  #9
                  Man that sucks. Pull it out, strip it down to the block, have it hot tanked and magnafluxed sp?. If the block is still good, just rebuild it. You could probably get a rebuild kit for around $500. Might as well get the heads checked out while your at it.
                  Photo Album
                  Ballast Install 1
                  Ballast Install 2
                  Amp Install
                  PPass Install
                  Alternator Install

                  Comment

                  • pj
                    • Oct 2003
                    • 323

                    • Rochester, MN

                    • 1991 SN 1996 SN
                    #10
                    Originally posted by surroundsound64
                    Just out of curiosity, what octane gas did you use?
                    We were running premium in it.
                    Originally posted by kelpy
                    How much water was in the sump - how overfilled was it.
                    It was overflowing pretty bad. I'm not sure exactly how much water. But, it must have been a lot.
                    Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For it is there you have been and there you will long to return. - Leonardo De Vinci

                    Comment

                    • pj
                      • Oct 2003
                      • 323

                      • Rochester, MN

                      • 1991 SN 1996 SN
                      #11
                      So, what does everybody think caused this failure? A crack in the block or head wouldn't cause the piston to come apart like that, would it? I'm thinking maybe a severe detonation. Is there any way to test my ProTec ignition to make sure it is functioning properly?
                      Once you have tasted flight, you will forever walk the earth with your eyes turned skyward. For it is there you have been and there you will long to return. - Leonardo De Vinci

                      Comment

                      • jackcham
                        • Sep 2006
                        • 1


                        #12
                        new 351 marine engine

                        I am sure I can help on this. Call 1-800-262-2929.

                        Jack

                        Comment

                        Previous template Next
                        Working...
                        X