50:1 -or- 24:1?????

[NeWcS]

Re: 50:1 -or- 24:1?????

So it's mostly agreed that the proper mix is 24:1<br /><br />Thanks for everyone's input<br /><br /><br />-Jay

 

[DHPMARINE]

Re: 50:1 -or- 24:1?????

I always thought 24:1 was the old standard because back then 30w motor oil was used,and when two stroke 50:1 came out,it worked at 1 pint to 6 gallons for all OMC outboards.<br />This was because it was a better oil,and stayed suspended (mixed) better.<br />Never seemed to adversly affect any of my customers motors thru those years.<br />Also OMC supported 100:1 for awhile,then decided it was ok for running,but not ok to sit for a few weeks,unrun.<br /><br />DHP

 

[Scaaty]

Re: 50:1 -or- 24:1?????

Originally posted by BoatBuoy:<br /> Does this mean you can't run 100:1 Amsoil in pre-1960? <br /><br /><br />Never mind. <br /><br /><br />I'll sit down and shut up.

Ya know, its stuff like this that I love about you guys.....a character in every croud!

 

[JB]

Re: 50:1 -or- 24:1?????

When OMC made the change to "24:1 in all engines, using high quality outboard oil and non-premium gasoline" it was referring to all engines manufactured before 1964. The statement is in my 1964 Johnson Service Manual.<br /><br />That was a change. Many of those older engines had previously called for 16:1 mix using SAE 30 Motor Oil.<br /><br />A note at the end of the passage said, "Starting with 1964 motors", Johnson's recommendation is to use a 50:1 mix, but only after a break-in period using the 24:1 mix recommended above.<br /><br />Many people have "gotten away with" using 50:1 in those older engines. Some have not. Oil is cheap compared to a grenaded engine.

 

[Chinewalker]

Re: 50:1 -or- 24:1?????

Well put JB.<br /><br />Keep in mind that the old motors were built a lot "looser" and used oil for more than just lubrication. It also acts as a sealant, particularly at the center main where the only seal is a ridged aluminum or bronze bearing on many models. The oil helps maintain that seal. Also, pretty much all of the earlier Johnrudes had thicker piston rings, as well as three rings per cylinder, which created more friction. By the mid to late 1960s they had gone to two rings per cylinder, plus making the rings thinner on most models, resulting in less friction. Oil isn't all about lubrication of bearings - many other factors in play...<br />- Scott

 

[rwise]

Re: 50:1 -or- 24:1?????

NeWcS<br />I have a 58 johny 35, I bought a 6 gal can at wally world nad use it to mix the gas oil and then fill the tank from it when it is needed. Also run 24:1. Why take a chance, it's worked 36 years with this mix, yes the oil is getting better.

 

[funpilot]

Re: 50:1 -or- 24:1?????

I'm with JB on this, Mercury OK'd 50:1 on my old 1963 45 hp, but I went with that because the factory blessed it. JB once kindly pointed out to me that if Johnson thought it was a good idea, they would say so.<br /><br />My 1952 Tolleycraft Utility with the 1963 45 hp Merc had simple six gallon Mercury tanks. One time when I was picking up Merc Oil, a 'freebie' was a really cool dipstick marked in gals and oz of oil, in reverse. You just stuck it in your tank, and it would tell you how many gals and how many oz of oil you needed to fill your tank. A neat tool that I kept for many years.<br /><br />When I premix, I usually go half on Gas, put in the oil, slosh it, and then put in the rest of the Gasoline. Works for me...<br /><br />take care,<br />fp