2006 Yamaha F250 4 Stroke 6 Cylinder

[nrtbmw]

Engine was running very well after replacing the VST. One day after replacement, discovered a little oil in the transom well after the engine was tilted up on my mooring. Marina performed a leak test and found pressure leaking. They then performed a Yamaha Internal Engine Cleaning and found some carbon build up and some cylinder wear. Was informed to double the amount of Yamaha Ring Free and problem seems to have ceased. Engine has 938 hours but has been well maintained and is running well. Debating whether or not to repower because of number of hours. What have other members experienced with life expectancy of the F250? At $ 22,000 +, would rather not repower. Would appreciate your comments.
Thanks

 

[wspitler]

I have two of the same 2006 engines. The oil in the transom well could have come from a recent filter change, but if it came from a leak in the engine case or oil pan then that is a corrosion problem that ring free won't help. The intake plenum must be removed to get to the VST so there could have been residual oil from that area that was not cleaned up as well. I found a little oil there when I did mine. I'd continue to monitor that oil leak and see if you can determine the source if it recurs after a good cleaning inside the cowling. I get that almost every time I change the filter no matter how hard I try to prevent it. The oil could have come from higher up on the engine and run down into the cowling. One of my two engines had the exhaust corrosion issue at 250 hours and, if extensive, that can cause oil leaks. I now have 1000 hours on both and they both run great. I have changed the VST filters and LP filters once and they were both quite dirty. I assume you meant VST filters and not the entire VST tank itself. Removing the VST tank doesn't require disconnecting any oil lines.

In my opinion, four strokes rings don't typically carbon up like two strokes do. Compression and leakdown tests can vary a lot if not done properly. Check the condition of the plugs to judge cylinder condition. If there are no other symptoms such as loss of power, etc. keep on running your engine. These engines can run well over 2000 hours without problems. I plan to run mine until I have a major problem, but right now I use synthetic oil and marine techron additive in ethanol free gas. Good Luck with yours.

 

[nrtbmw]

I have two of the same 2006 engines. The oil in the transom well could have come from a recent filter change, but if it came from a leak in the engine case or oil pan then that is a corrosion problem that ring free won't help. The intake plenum must be removed to get to the VST so there could have been residual oil from that area that was not cleaned up as well. I found a little oil there when I did mine. I'd continue to monitor that oil leak and see if you can determine the source if it recurs after a good cleaning inside the cowling. I get that almost every time I change the filter no matter how hard I try to prevent it. The oil could have come from higher up on the engine and run down into the cowling. One of my two engines had the exhaust corrosion issue at 250 hours and, if extensive, that can cause oil leaks. I now have 1000 hours on both and they both run great. I have changed the VST filters and LP filters once and they were both quite dirty. I assume you meant VST filters and not the entire VST tank itself. Removing the VST tank doesn't require disconnecting any oil lines.

In my opinion, four strokes rings don't typically carbon up like two strokes do. Compression and leakdown tests can vary a lot if not done properly. Check the condition of the plugs to judge cylinder condition. If there are no other symptoms such as loss of power, etc. keep on running your engine. These engines can run well over 2000 hours without problems. I plan to run mine until I have a major problem, but right now I use synthetic oil and marine techron additive in ethanol free gas. Good Luck with yours.

 

[nrtbmw]

Thanks Bill. Appreciate the input.

 

[Doc Stressor]

I would not recommend running Ringfree at 2X the recommended dose. Yamaha no longer recommends owners doing their own shock treatment. They only want dealers to do it. That's because Techron derivatives tend to accumulate in the oil at high doses and can contribute to oil breakdown. The dealer changes the oil after the high dose shock treatment.

The standard dose of Ringfree is fine for controlling deposits under normal conditions. As Bill said, 4-strokes don't typically develop ring and combustion chamber deposits except when they burn low quality or stale gasoline. Use the standard dose of Ringfree and a stabilizer to reduce fuel degradation. The Chevron fuel additive is a much cheaper alternative since it also contains a fuel stabilizer.

 

[igblack87]

I'm following all of this...new to the F250 2006 myself. Lay on the info!

 

[nrtbmw]

I would not recommend running Ringfree at 2X the recommended dose. Yamaha no longer recommends owners doing their own shock treatment. They only want dealers to do it. That's because Techron derivatives tend to accumulate in the oil at high doses and can contribute to oil breakdown. The dealer changes the oil after the high dose shock treatment.

The standard dose of Ringfree is fine for controlling deposits under normal conditions. As Bill said, 4-strokes don't typically develop ring and combustion chamber deposits except when they burn low quality or stale gasoline. Use the standard dose of Ringfree and a stabilizer to reduce fuel degradation. The Chevron fuel additive is a much cheaper alternative since it also contains a fuel stabilizer.

Thanks Doc

 

[grady33]

I have 2 2006 F250’s on my 330 and 1,380 hours on both. I use only nonethanol fuel And change oil, lower unit, spark plugs, fuel filters, water separator etc at the end of the season (end of Oct) before lay up. Have always used ring free and change VST filter, engine anodes, thermostats, water pump etc every few years. Engines have run great and never any problems (knock on wood)! Checked for exhaust corrosion 2 years ago and didn’t see any and plan to check again when we pull the boat end of month. I did change the timing belt at around 800 hours. I flush engines after every trip. Not sure what else I can do but if anyone has any suggestions I’d love to hear it. I too was thinking of moving up to 300s but that’s expensive and these engines are still running great.

 

[Meanwhile]

Also have 2006 twin 250s. About 1700 hours on them. One engine made some oil so I inquired of my shop I use. They told me that it is common in our area. We have a short run to the bar, and then almost never run full throttle in the PNW ocean. He wants me to run the engines at full throttle for the 3 miles from the bar to a speed limit area. He also suggested them doing a shock treatment.

I had the timing belt checked at 1000 hours. The new mechanic returned from a Yamaha school in Feb. They now say to replace, not check the timing belt per Yamaha advise. I'll have that done Nov.

I'm hoping the making oil problem is not a big deal. The Nov. service should explain much.

 

[grady33]

Forgot to add, after a long day offshore I usually run the engines full throttle for about a minute as we approach the marina. Was told that would help keep rings clean. I don’t know.

 

[nrtbmw]

I have 2 2006 F250’s on my 330 and 1,380 hours on both. I use only nonethanol fuel And change oil, lower unit, spark plugs, fuel filters, water separator etc at the end of the season (end of Oct) before lay up. Have always used ring free and change VST filter, engine anodes, thermostats, water pump etc every few years. Engines have run great and never any problems (knock on wood)! Checked for exhaust corrosion 2 years ago and didn’t see any and plan to check again when we pull the boat end of month. I did change the timing belt at around 800 hours. I flush engines after every trip. Not sure what else I can do but if anyone has any suggestions I’d love to hear it. I too was thinking of moving up to 300s but that’s expensive and these engines are still running great.

Thx GreatGrady. Appreciate the input.

 

[nrtbmw]

Forgot to add, after a long day offshore I usually run the engines full throttle for about a minute as we approach the marina. Was told that would help keep rings clean. I don’t know.

Also have 2006 twin 250s. About 1700 hours on them. One engine made some oil so I inquired of my shop I use. They told me that it is common in our area. We have a short run to the bar, and then almost never run full throttle in the PNW ocean. He wants me to run the engines at full throttle for the 3 miles from the bar to a speed limit area. He also suggested them doing a shock treatment.

I had the timing belt checked at 1000 hours. The new mechanic returned from a Yamaha school in Feb. They now say to replace, not check the timing belt per Yamaha advise. I'll have that done Nov.

I'm hoping the making oil problem is not a big deal. The Nov. service should explain much.

Thx NoBail. Was told by the Yamaha folks to have a compression check when Moonshine is pulled out in October. If readings are above the minimum of 107.3 and there is no more than a 10 % difference between the 6 cylinder readings, I sgould be OK.