centralcoast
New member
I'm new to inboards/sterndrives. I recently acquired a boat with a 300hp 2006 Mercruiser Mag 350 MPI Horizon and a Bravo 3 outdrive. It has 1600 hours on it and a SmartCraft gauge that shows temp/rpms/alarms/engine hours, etc. I am considering scrapping/selling this motor eventually to re-power with an outboard, but I want to give it a chance first.
I have a few questions that hopefully someone here can answer:
- This is a raw-water cooled motor, with a thru-hull pickup at the stern on the bottom of the hull. The thru-hull fitting has a seacock, and is teed into the strainer before entering the raw water system on the motor. There is also a hose coming into the tee from the outdrive. Is it safe to run the motor at idle for extended periods of time with muffs on the outdrive water pickup, with the seacock closed (so water flows into the motor)? This method seems to pulling a good amount of water into the raw water system, but I have seen conflicting information online.
- The motor starts and runs at idle, but dies after a few minutes. There was old fuel in the tank (110 gallons) which seemed to be watered down a bit. I pumped it (about 10 gallons) out with fuel filters and disposed of it. Pulled out some debris during this process as well. I added 5 gallons 91 octane this weekend and drove the boat around on the trailer to slosh things around. Pumped/filtered the fuel out again, and then put clean fuel back in. Swapped out the in-line fuel/water separator too. Motor starts right up and still dies eventually. No overheat warnings or anything like that. Could it be that the amount of fuel I added (5 gallons) is too small for the pickup to grab and prime? There is no fuel priming bulb.
- The seller suspected that the power steering pump needed replacement and could possibly be causing the motor shutdown at idle. This doesn't make any sense to me. Any ideas?
I have a few questions that hopefully someone here can answer:
- This is a raw-water cooled motor, with a thru-hull pickup at the stern on the bottom of the hull. The thru-hull fitting has a seacock, and is teed into the strainer before entering the raw water system on the motor. There is also a hose coming into the tee from the outdrive. Is it safe to run the motor at idle for extended periods of time with muffs on the outdrive water pickup, with the seacock closed (so water flows into the motor)? This method seems to pulling a good amount of water into the raw water system, but I have seen conflicting information online.
- The motor starts and runs at idle, but dies after a few minutes. There was old fuel in the tank (110 gallons) which seemed to be watered down a bit. I pumped it (about 10 gallons) out with fuel filters and disposed of it. Pulled out some debris during this process as well. I added 5 gallons 91 octane this weekend and drove the boat around on the trailer to slosh things around. Pumped/filtered the fuel out again, and then put clean fuel back in. Swapped out the in-line fuel/water separator too. Motor starts right up and still dies eventually. No overheat warnings or anything like that. Could it be that the amount of fuel I added (5 gallons) is too small for the pickup to grab and prime? There is no fuel priming bulb.
- The seller suspected that the power steering pump needed replacement and could possibly be causing the motor shutdown at idle. This doesn't make any sense to me. Any ideas?