Today I fired up my brand new Nissan 8hp 4 stroke outboard for the first time. Being a powerboater, I am not used to having a manual choke. Long story short, I ran the motor for about 30 minutes with the choke on (pulled out). I was running it in neutral in the driveway for break in. The I realized I forgot to open the choke, and when I opened it the motor ran MUCH smoother and quieter. While the choke was closed, there was alot of black soot coming out from around the prop, enough to turn the white prop black. It kept running for 30 minutes at idle speed while I was in the house, but ran alot rougher and louder than when I closed the choke and it got the proper amount of fuel. It restarted several times with no problem. I am concerned that I may have damaged or shortened the life of the motor. So the question is, could I have damaged the motor by doing this? Also, is it a good idea to run the motor at 1/2 or 3/4 throttle for break in while in neutral, or should break in be done under load while the prop is turning? This is not addressed in the owner's manual. I will greatly appreciate any responses!
- Status
Breath easy
The only damage you may have done is foul your spark plugs. If after the choke was pushed in and the motor began to run okay means that your fuel and air mixture was then correct. The black in the water was unburned fuel. And as far as the break in time,I don't think there is a break in period or the owners manuel would have addressed that concern. If you feel you need to run the motor I would do it on the boat under a load in the slip. Put it in gear and let it run for a little while. I would not raise the RPM but to a high idle or a little more. Fair winds Don
The only damage you may have done is foul your spark plugs. If after the choke was pushed in and the motor began to run okay means that your fuel and air mixture was then correct. The black in the water was unburned fuel. And as far as the break in time,I don't think there is a break in period or the owners manuel would have addressed that concern. If you feel you need to run the motor I would do it on the boat under a load in the slip. Put it in gear and let it run for a little while. I would not raise the RPM but to a high idle or a little more. Fair winds Don
Oil change a good idea.
Brian, I doubt you did any real harm other than sooting up the cylinder somewhat and that will clear up very quickly by itself in very short time. The concern I have is that the result of that unburned fuel is what is called "crankcase gas dilution". The unburned fuel will leak past the piston rings into the crankcase oil and will dilute its viscosity and lubricating properties to some extent. I would recomend changing the oil before restarting the motor. After that just use the motor under standard conditions and vary the power settings for the first couple of hours rather than running it at the same speed for long periods of time. Also avoid highest power settings for the first 2 hours. The engine will break in best under normal load conditions rather than static operations. Would you do the same to your new car as you did on the outboard? Probably not. Treat your boat motor the same. Enjoy your new motor and if you have any other concerns just send her to me and I'll run her for a couple of seasons to make sure it's OK. Ray
Brian, I doubt you did any real harm other than sooting up the cylinder somewhat and that will clear up very quickly by itself in very short time. The concern I have is that the result of that unburned fuel is what is called "crankcase gas dilution". The unburned fuel will leak past the piston rings into the crankcase oil and will dilute its viscosity and lubricating properties to some extent. I would recomend changing the oil before restarting the motor. After that just use the motor under standard conditions and vary the power settings for the first couple of hours rather than running it at the same speed for long periods of time. Also avoid highest power settings for the first 2 hours. The engine will break in best under normal load conditions rather than static operations. Would you do the same to your new car as you did on the outboard? Probably not. Treat your boat motor the same. Enjoy your new motor and if you have any other concerns just send her to me and I'll run her for a couple of seasons to make sure it's OK. Ray
Break-In proceedures
Breaking in a New Outboard Engine As always - check your manual. The following are general guidelines: ~Breaking in an engine should be done carefully. Some engine manufacturers specifically note that you should not idle the engine for too long. You will also want to avoid operating at a single speed, or at maximum speed (for very long) during the break-in period. ~ Use fuel with the right octane. Check your owner's manual for your engine. ~ Use fuel with no or very low alcohol content. Alcohol can damage some engines. ~ Most NEW engines are built to take fuels with some alcohol in the fuel. ~ Most 2 cycle engines use a 50:1 fuel mixture but for break-in this is usually a 25:1 mixture (TCW-3). The 8 HP Nissan 4-Stroke requires a 10-Hour “Break-In”, generally as follows: ~ Engine installed and “in-gear”. I don’t recommend operating tied to dock. ~ First 10 min. - Engine @ “Idle”. ~ Next 2 Hrs - Less than 1/2 Throttle (3,000 RPM max.). ~ Next 1 Hr - < 3/4 Throttle, with Full Throttle ‘burst’ for 1 min. every 10 min. ~ Next 7 Hours - 3/4 Throttle (about 4,000 RPM), with Full Throttle ‘burst’ for 2 min. every 10 min. ~ After your break-in period has been completed, you should change your lower unit gear case oil. http://www.nissanmarine.com/tech_talk/faqs.html#Q19 Nissan Manuals (Online download) http://www.nissanmarine.com/tech_talk/owners_manuals.html
Breaking in a New Outboard Engine As always - check your manual. The following are general guidelines: ~Breaking in an engine should be done carefully. Some engine manufacturers specifically note that you should not idle the engine for too long. You will also want to avoid operating at a single speed, or at maximum speed (for very long) during the break-in period. ~ Use fuel with the right octane. Check your owner's manual for your engine. ~ Use fuel with no or very low alcohol content. Alcohol can damage some engines. ~ Most NEW engines are built to take fuels with some alcohol in the fuel. ~ Most 2 cycle engines use a 50:1 fuel mixture but for break-in this is usually a 25:1 mixture (TCW-3). The 8 HP Nissan 4-Stroke requires a 10-Hour “Break-In”, generally as follows: ~ Engine installed and “in-gear”. I don’t recommend operating tied to dock. ~ First 10 min. - Engine @ “Idle”. ~ Next 2 Hrs - Less than 1/2 Throttle (3,000 RPM max.). ~ Next 1 Hr - < 3/4 Throttle, with Full Throttle ‘burst’ for 1 min. every 10 min. ~ Next 7 Hours - 3/4 Throttle (about 4,000 RPM), with Full Throttle ‘burst’ for 2 min. every 10 min. ~ After your break-in period has been completed, you should change your lower unit gear case oil. http://www.nissanmarine.com/tech_talk/faqs.html#Q19 Nissan Manuals (Online download) http://www.nissanmarine.com/tech_talk/owners_manuals.html
Did you run it in water?
Brian, Please tell me you had it in a barrel of water while running it in your driveway. The 30 minutes of choke will overheat things a bit but not hurt it. The soot will wash away. But, if you ran it without cooling water the rings, cylinder walls and SS water pump will have some premature wear. As it's still running well it's only latent-damage and it'll just shorten the motor's life a bit. (18 vs 20 years) Just change the oil and don't tell your dealer as he 'd likely kill your warranty if you ran it without coolant. If you ran it in water then: 1. Please excuse me for thinking otherwise; and, 2. The engine is fine as the bit of extra gas and heat would not be enough to damage anything. Just to be safe you may want to smell the oil dipstick. If the gas got past the rings you'll notice the smell of gas in the oil. An oil change will fix everything.
Brian, Please tell me you had it in a barrel of water while running it in your driveway. The 30 minutes of choke will overheat things a bit but not hurt it. The soot will wash away. But, if you ran it without cooling water the rings, cylinder walls and SS water pump will have some premature wear. As it's still running well it's only latent-damage and it'll just shorten the motor's life a bit. (18 vs 20 years) Just change the oil and don't tell your dealer as he 'd likely kill your warranty if you ran it without coolant. If you ran it in water then: 1. Please excuse me for thinking otherwise; and, 2. The engine is fine as the bit of extra gas and heat would not be enough to damage anything. Just to be safe you may want to smell the oil dipstick. If the gas got past the rings you'll notice the smell of gas in the oil. An oil change will fix everything.
Hey Gord, thanks for reminding me
of a question I had at the beginning of the season. I'm running a 1985 Evinrude Yatchtwin 8. Ct has switched to alcohol from MTBE and I believe it is a substantial ratio. How do I avoid this gas? Is the stuff at the marina fuel pumps sans the additives? How can you tell? Thanks
of a question I had at the beginning of the season. I'm running a 1985 Evinrude Yatchtwin 8. Ct has switched to alcohol from MTBE and I believe it is a substantial ratio. How do I avoid this gas? Is the stuff at the marina fuel pumps sans the additives? How can you tell? Thanks
OK
Yes, I did run it with water, a hose was attached using standard flushing earmuffs. I appreciate the responses. The oil reservoir does smell like gas, so I will change the oil before running again. I guess I will just wait and perform the break in under load. Thanks!
Yes, I did run it with water, a hose was attached using standard flushing earmuffs. I appreciate the responses. The oil reservoir does smell like gas, so I will change the oil before running again. I guess I will just wait and perform the break in under load. Thanks!
Oxygenators
MTBE (methyl tertiary-butyl ether) is used as a gasolene oxygenator, in lieu of Ethanol or other oxygenates (‘seasonally’ required by EPA). Due to possible adverse health & environmental concerns, MTBE is being phased out of general use. I believe that the vender must post the Ethanol (alcohol) content of his gasoline. You may get alcohol-free gas during the summer months (oxygenators are “required” in winter). Best bet, it to ask your retailer. Gord
MTBE (methyl tertiary-butyl ether) is used as a gasolene oxygenator, in lieu of Ethanol or other oxygenates (‘seasonally’ required by EPA). Due to possible adverse health & environmental concerns, MTBE is being phased out of general use. I believe that the vender must post the Ethanol (alcohol) content of his gasoline. You may get alcohol-free gas during the summer months (oxygenators are “required” in winter). Best bet, it to ask your retailer. Gord
Fuel oxygenators
In New York (as in CT and CA) MTBE can no longer be used because of the health problems from fuel tank leaks. They switched over to ethanol instead. All the pumps around here have stickers that say the gas contains 10% Ethanol. If you are in an ethanol-using state, I don't think you are going to avoid using it. Most of what I have read says that using an ethanol-blend fuel will not harm an engine. I have seen cautions not to use more than 15-20% ethanol, however, and never to use methanol (wood alcohol). If you are in an area that uses both MTBE and ethanol, be sure not to mix fuels containing ethanol and MTBE. I have read that if you do this, over (a relatively short)time the mixed fuel will turn to a sludge in your tank and fuel lines. Messy, to say the least. Urban legend? I'm not sure but I'm not taking a chance either. Brad
In New York (as in CT and CA) MTBE can no longer be used because of the health problems from fuel tank leaks. They switched over to ethanol instead. All the pumps around here have stickers that say the gas contains 10% Ethanol. If you are in an ethanol-using state, I don't think you are going to avoid using it. Most of what I have read says that using an ethanol-blend fuel will not harm an engine. I have seen cautions not to use more than 15-20% ethanol, however, and never to use methanol (wood alcohol). If you are in an area that uses both MTBE and ethanol, be sure not to mix fuels containing ethanol and MTBE. I have read that if you do this, over (a relatively short)time the mixed fuel will turn to a sludge in your tank and fuel lines. Messy, to say the least. Urban legend? I'm not sure but I'm not taking a chance either. Brad
not likely
Brian, I would think you did not damage anything.It did run very rich an with the choke on it was too much gas not enough air,however as you noted it ran fine after putting the choke in giving it proper air/fuel mixture. As others suggested change the oil,if you want put in new or clean the spark plugs and forget about it.Follow break in procedure and go sailing.
Brian, I would think you did not damage anything.It did run very rich an with the choke on it was too much gas not enough air,however as you noted it ran fine after putting the choke in giving it proper air/fuel mixture. As others suggested change the oil,if you want put in new or clean the spark plugs and forget about it.Follow break in procedure and go sailing.
- Status