I'll try to keep this short........I have to share the good news, since I learned a lot and got some great advise from people on here. 
<br /><br />A quick history.....Last year I bought a '91 boat with a rebuilt motor. After only 20 hours, the motor blew (seized all 4 pistons). Dealer would not warranty anything. <br />I still don't have a cause for the failure but found lots of little things that contributed.<br />Cylinders were undersize .003<br />VRO was never checked over (or changed)<br />Water passages were all crusty (block and head)<br />Thermostats were 12 years old<br />Cooling hoses were half blocked with silicone.<br /><br />Well after many moons of cleaning and inspecting, she is back together. Only other real difference, is I'm premixing instead of relying on the VRO. I can always install a new pump later. So far, I have burned app 25 gallons of fuel (about 10 hours) and it has never run this good before. It's like a different boat. It leaps out of the water and is on plane in seconds. I love it.<br /><br />OK, only one question for you experts.<br />Now that I have a few hours, is it safe to run across the lake at 5500 rpm???<br />I have read many posts about these engines setup for 5800, so I'm interested to see how it runs up there. I have tried a quick burst over 5000 but never hold it there, but I can feel it wants to go.
<br /><br />A quick history.....Last year I bought a '91 boat with a rebuilt motor. After only 20 hours, the motor blew (seized all 4 pistons). Dealer would not warranty anything. <br />I still don't have a cause for the failure but found lots of little things that contributed.<br />Cylinders were undersize .003<br />VRO was never checked over (or changed)<br />Water passages were all crusty (block and head)<br />Thermostats were 12 years old<br />Cooling hoses were half blocked with silicone.<br /><br />Well after many moons of cleaning and inspecting, she is back together. Only other real difference, is I'm premixing instead of relying on the VRO. I can always install a new pump later. So far, I have burned app 25 gallons of fuel (about 10 hours) and it has never run this good before. It's like a different boat. It leaps out of the water and is on plane in seconds. I love it.<br /><br />OK, only one question for you experts.<br />Now that I have a few hours, is it safe to run across the lake at 5500 rpm???<br />I have read many posts about these engines setup for 5800, so I'm interested to see how it runs up there. I have tried a quick burst over 5000 but never hold it there, but I can feel it wants to go.