medic3538
Member
- Aug 17, 2008
- 151
- Boat Info
- 2005 260 Sundancer. 2003 F250 Super Duty V10 Ford Tow. 5.0 KW Kohler genset. Old school Naman GPS.
- Engines
- 350 MAG MPI, Bravo 2 drive.
Original Post:
Major engine failure
Was 30 min into a cruise and the alarm sounded. A quick look at the gauges while throttling down showed temp, oil pressure, RPM and speed to be normal. Before I could get all the way down to idle, the Smart Craft system beat me to it and shut the engine down.
Opened the engine hatch and there is a moderate smoke condition coming from wires melting to manifold covers and paint melting. I did not attempt to restart and just called Tow Boat US.
Dropped boat at Sea Ray and as of Monday we have the following:
They placed the bunny ears on the outdrive and she started and ran. There was good water flow out the exhaust bellows. The manifold covers heated up very quickly and they shut the engine down. They were slighly confused and worried as they were seeing water flow, but still heating up.
So, they started from the top and worked down. Pulled risers, manifold covers, spark plugs and water pump.
Risers were not pulled apart as of Monday, but they were doing leak testing. Compression on 2 of 4 starboard cylinders was low and the tech saw signs of salt water in the cylinders. The spark plugs on the low compression cylinders showed white flashing at their bases suggesting extreme heat.
The service manager stepped over and started talking to me about the risers. He said that on the 04-06 350 mag risers that they (apologize if I get this wrong, just trying to recall what/how he said) have 2 parallel channels running through them. 1 for exhaust and 1 for water flow. He feels that maybe the channels have corroded into eachother, causing water backflow into cylinders. It still doesn't explain why there is water flow and high heat, but it is clear that these 2 cylinders have some problems and I am just wating for the final verdict.
I will keep ya'll informed as to the final problem. Was planning on changing risers at the end of the season e.g September 1st-ish. That will be a bite on the @$$ if I missed it by 3 weeks.
UPDATE: The manifolds have been remachined. The 2 cylinders that were low on compression had their pistons changed out as the conclusion to compression loss was an over heat issue that damaged the rings. I had the risers changed out as I was going to do it anyway. The risers were "cracked" (a term they use at the shop to see what damage there may be) and there appeared to be slight corrosion inside, but no major damage as to indicate water back up into the engine.
So, the main question I posed is..what the hell happened and what didn't I do to prevent the probem. Answer: "You have 476 hours on salt water sir."
I have ordered a aftermarket fresh water cooling system and will install that with a "more mechanically inclined than me" buddy to help avoid this costly mess. Hopefully just a bi-yearly riser change and not 4k every 500 hours.
I am going to do a line by line sit down with the service manager and try to understand this better and I'll update a final time.
I am sure we are all wondering final cost. I was told to expect $3500 - $4000. Again, line by line inspection of the billing wont save me any money I am sure, but it should make me understand better.
Hey, it's all part of owning a boat. I have a buddy who just dropped 10K on golf clubs, plane fare and greens fees. He gets to use that plane ride and play that course 1 time. Once my boat is back online, another 500 hours of pure joy.
Major engine failure
Was 30 min into a cruise and the alarm sounded. A quick look at the gauges while throttling down showed temp, oil pressure, RPM and speed to be normal. Before I could get all the way down to idle, the Smart Craft system beat me to it and shut the engine down.
Opened the engine hatch and there is a moderate smoke condition coming from wires melting to manifold covers and paint melting. I did not attempt to restart and just called Tow Boat US.
Dropped boat at Sea Ray and as of Monday we have the following:
They placed the bunny ears on the outdrive and she started and ran. There was good water flow out the exhaust bellows. The manifold covers heated up very quickly and they shut the engine down. They were slighly confused and worried as they were seeing water flow, but still heating up.
So, they started from the top and worked down. Pulled risers, manifold covers, spark plugs and water pump.
Risers were not pulled apart as of Monday, but they were doing leak testing. Compression on 2 of 4 starboard cylinders was low and the tech saw signs of salt water in the cylinders. The spark plugs on the low compression cylinders showed white flashing at their bases suggesting extreme heat.
The service manager stepped over and started talking to me about the risers. He said that on the 04-06 350 mag risers that they (apologize if I get this wrong, just trying to recall what/how he said) have 2 parallel channels running through them. 1 for exhaust and 1 for water flow. He feels that maybe the channels have corroded into eachother, causing water backflow into cylinders. It still doesn't explain why there is water flow and high heat, but it is clear that these 2 cylinders have some problems and I am just wating for the final verdict.
I will keep ya'll informed as to the final problem. Was planning on changing risers at the end of the season e.g September 1st-ish. That will be a bite on the @$$ if I missed it by 3 weeks.
UPDATE: The manifolds have been remachined. The 2 cylinders that were low on compression had their pistons changed out as the conclusion to compression loss was an over heat issue that damaged the rings. I had the risers changed out as I was going to do it anyway. The risers were "cracked" (a term they use at the shop to see what damage there may be) and there appeared to be slight corrosion inside, but no major damage as to indicate water back up into the engine.
So, the main question I posed is..what the hell happened and what didn't I do to prevent the probem. Answer: "You have 476 hours on salt water sir."
I have ordered a aftermarket fresh water cooling system and will install that with a "more mechanically inclined than me" buddy to help avoid this costly mess. Hopefully just a bi-yearly riser change and not 4k every 500 hours.
I am going to do a line by line sit down with the service manager and try to understand this better and I'll update a final time.
I am sure we are all wondering final cost. I was told to expect $3500 - $4000. Again, line by line inspection of the billing wont save me any money I am sure, but it should make me understand better.
Hey, it's all part of owning a boat. I have a buddy who just dropped 10K on golf clubs, plane fare and greens fees. He gets to use that plane ride and play that course 1 time. Once my boat is back online, another 500 hours of pure joy.
Last edited:
