cahhtravis4
New member
I have a 2005 Tige boat with a Marine Power GM 5.7 liter 340hp multi-port fuel injection engine with low hours (300-400 hours). I was using it for wakeboarding/skiing last weekend and started noticing that I had some blue smoke out of the exhaust, then later I noticed that oil pressure was very low at idle but ok at RPMs above that, so I shut it down immediately and checked the oil level and found that it was 3 quarts low. After pulling the boat, I checked the (warm engine) compression on all the cylinders and noticed that cylinder 5 had no compression at all and cylinder 3 had only 70 psi (all the other cylinders had around 160-170 psi). I pulled the head and noticed that the head gasket between 3 and 5 was burnt through, cylinder scoring on both cylinder walls where 3&5 come together and cylinder 5 had a chunk out of the inner piston showing the ring underneath, see attached pictures.
My plan is to replace the engine with a new 5.7 long block, $2750. However, I would like to know the root cause of my failure, so that I don't have this same issue with the new engine in a couple months.
Thanks ahead of time for any help.
My plan is to replace the engine with a new 5.7 long block, $2750. However, I would like to know the root cause of my failure, so that I don't have this same issue with the new engine in a couple months.
Thanks ahead of time for any help.