nitedmn
Petty Officer 3rd Class
- Joined
- Jul 3, 2005
- Messages
- 78
I'm sure I know the answer to this already but I'm just not ready to accept it yet. I'll give you the whole story (in a shotened form) from the begining so you have all the info.<br /><br />Motor info:<br />Mercruiser 898 (GM 305)<br /><br />Put boat in water last summer and it stalled after it warmed up and would not refire. Motor would still crank without problems but would not fire.<br /><br />Pulled boat out of water, brought it home and began to trouble shoot (moter started fine once it cooled down).<br /><br />Discovered cracked exaust manifold that seemed to be caused by engine overheating. Engine still started and ran fine (sounded perfect) when cold except for the water that was getting into the oil. Engine never got so hot that it would not crank.<br /><br />Pulled outdrive. Drained oil (now turned to syrup). Changed filter. Filled with fresh oil. started motor and let it run for about 15 to 30 seconds, without water, to pump the rest of the bad oil out of the engine. When I started the motor this time I heard a strange knocking sound from the moter. My first thought was the circulating pump, since it was dry. Then I drianed oil, changed filter, and filled with fresh oil again.<br /><br />Had no money for new manifolds so the boat sat for the rest of the summer. Before winter I removed the old manifolds, circulating pump, sprayed fogging oil in all the cylinders, and drained the block (winterized it as best I could without starting it)<br /><br />Yesterday I pulled the boat out of storage. I pulled the curculating pump apart and didn't see any problems with it. I put the pump back on and installed the new manifolds I bought during the winter. I then took my garden hose an stuck it in the hole where the water would normaly be pumped into the motor (remember the outdrive is still removed).<br /><br />Good news. I fixed the water in the oil problem. I now have good water flow to both manifolds and the engine block. Oil is level isn't changing.<br /><br />Now I start the motor (out drive still removed with my garden hose providing water to the motor). After a few tries I get the motor to fire and run. Seems to run good except I still have that knocking sound.<br /><br />I removed the belt going around the crank, alternator, and water pump and start the motor again for a second or two. I still hear the noise so it's definatly not the water pump.<br /><br />I have this noise narrowed down to two things. As mentioned before I'm pretty sure I know which one is correct but I want to check before I go through the trouble of pulling the motor.<br /><br />1. This noise started after I removed the outdrive. Would running the motor without the outdrive possibly cause any additional noise?<br /><br />2. I spun a bearing in the motor and will need to pull the motor to fix it. (oh... This motor has less then 100 hours on it although it was sitting for about 3-5 years before I bought it)