I am not into boats at all, but 100:1 on outbaord marine oil seems a little scary. No wonder they wear out so fast. What is a more realistic value? The engine will be worked pretty good at times. No synthetic will be used, but regular outboard oil.
Johnson / Evinrude 9.9HP outboard 100:1
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If dino I would not go away from 50-1. If Amsoil 100-1 I would do it but you could run it at 75-1 on up to 100-1 for a little extra protection.
Amsoil claims they use no solvents in the 100-1 oils. I don't think this is the case with most 50-1 oil's.
Amsoil claims they use no solvents in the 100-1 oils. I don't think this is the case with most 50-1 oil's.
So at 50:1 it should be safe?
Mix the oil at 50:1. Some manufacturers recommended 100:1 for a few years then went back to 50:1. You are right about wearing out a motor fast at 100:1. Amsoil says their oil can be run at 100:1 but even some of the Amsoil sales people on here have said 80:1 if you read between the lines. If you use Amsoiil mix it how you want. If you use anything else mix it 50:1 regardless if it is regular TCW3 or synthetic TCW3. Decarb the engine once or twice a year and enjoy. Those 9.9 and 15 motors seem to last a long time.
Actually that's not super tough duty for a 100:1 oil. Amsoil 100:1 Saber Outboard will be fine and won't cause excess wear. I think if you run it at 50:1, you will be spewing to much oil. If you get all worried, the 80:1 is fine as well.
Yes I have run the 100-1 Amsoil before at 80,85-1 ratio before.
If you are going to run at 50-1 don't use the Amsoil 100-1 oil.
I don't think I would run just any 2 stroke dino or syn oil at more than 50-1 ratio.
If you are going to run at 50-1 don't use the Amsoil 100-1 oil.
I don't think I would run just any 2 stroke dino or syn oil at more than 50-1 ratio.
100:1 will wear out the connecting rod bearings, not pistons and rings. I found out the hard way!
Thanks OMC..
Thanks OMC..
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I have posted here many times about some two stroke oil testing our company did for Mercury Marine.
Bottom line,
32 to 1 provides all the protection possible in nearly every situation. Except very highly loaded engines such as 48HP 125cc Kart engines.
16 to 1 will result in more HP as will 8 to 1 if you can get it to run cleanly.
50 to 1 provides enough protection for many non racing applications but does result in very slightly higher wear rates of certain components in some high performance engines. This includes reed valves and crank bearings.
100 to 1 results in much higher wear rates regardless of type of oil used. It will also result in outright engine failure in many highly loaded racing applications. Kart engines and 500cc GP bikes are good examples of unsuitable applications.
My suggestion,
Use a quality TCW-III oil at 50 to 1.
Bottom line,
32 to 1 provides all the protection possible in nearly every situation. Except very highly loaded engines such as 48HP 125cc Kart engines.
16 to 1 will result in more HP as will 8 to 1 if you can get it to run cleanly.
50 to 1 provides enough protection for many non racing applications but does result in very slightly higher wear rates of certain components in some high performance engines. This includes reed valves and crank bearings.
100 to 1 results in much higher wear rates regardless of type of oil used. It will also result in outright engine failure in many highly loaded racing applications. Kart engines and 500cc GP bikes are good examples of unsuitable applications.
My suggestion,
Use a quality TCW-III oil at 50 to 1.
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Originally Posted By: lars11
Explain to me how 16/1 (more lube oil) will increase HP. Just curious.
First off, our testing was done on inline 6 cylinder 150HP race tuned outboard engines. However, in the interest of full disclosure, our testing was based on testing by McCullough, Husqvarna and other 2 stroke manufacturers of the time.
The theory was that the higher levels of oil promoted better piston ring sealing and better heat transfer. In addition, the oil contains energy that could be used by the engine. The burn rate of the oil (and it's oxygen requirements) was significantly different than the gasoline and therefore tended to add to the BMEP. However, it does seem that peak pressures did increase also.
You must also remember that jetting changes were required to manage the test properly. More oil in the mix tended to reduce the fuel available, so slightly increased jet size was required.
Explain to me how 16/1 (more lube oil) will increase HP. Just curious.
First off, our testing was done on inline 6 cylinder 150HP race tuned outboard engines. However, in the interest of full disclosure, our testing was based on testing by McCullough, Husqvarna and other 2 stroke manufacturers of the time.
The theory was that the higher levels of oil promoted better piston ring sealing and better heat transfer. In addition, the oil contains energy that could be used by the engine. The burn rate of the oil (and it's oxygen requirements) was significantly different than the gasoline and therefore tended to add to the BMEP. However, it does seem that peak pressures did increase also.
You must also remember that jetting changes were required to manage the test properly. More oil in the mix tended to reduce the fuel available, so slightly increased jet size was required.
Originally Posted By: lars11
Ok, my feeling has always been that with more oil, the engine will be weaker and dirtier and with less oil, it will be peppier and cleaner and easier to start. But that's with no other changes so I see what you mean.
When we ran the engines with 8 to 1, there was nearly no carbon buildup on the piston and cylinder head, as the oil kept internal parts extremely clean. However, the exhaust was full of oil and residue.
There is no question that properly tuned engines are more responsive with high quantities of oil in the gas (up to a point, maybe 16 to 1).
Ok, my feeling has always been that with more oil, the engine will be weaker and dirtier and with less oil, it will be peppier and cleaner and easier to start. But that's with no other changes so I see what you mean.
When we ran the engines with 8 to 1, there was nearly no carbon buildup on the piston and cylinder head, as the oil kept internal parts extremely clean. However, the exhaust was full of oil and residue.
There is no question that properly tuned engines are more responsive with high quantities of oil in the gas (up to a point, maybe 16 to 1).
Cujet, what year were these tests done?
To clarify my earlier post: my take on the 100:1 proplem was not that piston/cylinder wear was the big problem. It was storage problems as the bottem end did not retain the same amount of oil as with 50:1. The engines needed to be fogged before storage, and most did not do that. This is just my perception of the problem based on things I have read.
I did buy an 87 Johnson that had connecting rod bearing worn out. PO used 100:1 I don't think Amsoil would make a 100:1 product if there was a possiblity of liabilty from owners due to pre-mature wear. Still takes a while to get used to when you grew up in a 50:1 world...
To clarify my earlier post: my take on the 100:1 proplem was not that piston/cylinder wear was the big problem. It was storage problems as the bottem end did not retain the same amount of oil as with 50:1. The engines needed to be fogged before storage, and most did not do that. This is just my perception of the problem based on things I have read.
I did buy an 87 Johnson that had connecting rod bearing worn out. PO used 100:1 I don't think Amsoil would make a 100:1 product if there was a possiblity of liabilty from owners due to pre-mature wear. Still takes a while to get used to when you grew up in a 50:1 world...
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