synthetic oil and 1:24 mix engines.

[rolmops]

Hello.<br />The other day I overheard a conversation.<br />One man claimed that the new synthetic oils are so good that you can safely run engines with babbit bearings on a 1:50 mix.<br />And is it true that synthetic oil is bio-degradable?<br />I would love to hear some ideas and opinions about this.<br />Thank you.

 

[Yepblaze]

Re: synthetic oil and 1:24 mix engines.

And they said diesel smoke was non toxic.<br /><br />You asked for opinions.<br /><br />Apparently it will have the lubricity, but I have been led to believe there is some cushioning value in the crude based products that is helpfull to crank/rod.<br /><br />Now being less than the best alloy rod bearing material to begin with...................

 

[DJ]

Re: synthetic oil and 1:24 mix engines.

rolmops,<br /><br />Synthetics will work just fine. I wouldn't quite go to 50:1. You can go somewhere in between.<br /><br />Diesel isn't toxic-it smells like MONEY$$.

 

[my new fishmaster]

Re: synthetic oil and 1:24 mix engines.

I am anti synthetics for both cars and marine equipement. I do think syn 4 stroke motor oil has its place but after using Redline mtl,mt90,75w90 gear oil had nothing but problems with both my BMW and Jeep. My 89 80Mercury was running the fancy Blue bottle stuff from WalMart had fuel pump problems to each his own but I will stick with quicksilver tcw3 in my new Force.

 

[Lark40]

Re: synthetic oil and 1:24 mix engines.

People who make statements about it being OK to run 50:1 mix in pre-1964 engines usually don't own any.<br /><br />This would be especially true for synthetic oil enthusiasts, who usually own engines they bought new.<br /><br />So, why accept advice from non-participants that contradicts many years of experience?

 

[steelespike]

Re: synthetic oil and 1:24 mix engines.

Dont mess with oil mix ratios.Stick with original.Ratio changes are more a result of engine design improvements than oil technology.<br /> Spike

 

[DJ]

Re: synthetic oil and 1:24 mix engines.

Couldn't disagree more with LARK 40. I have a 58 7 1/2 Rude that I've been running at 40:1 for over 15 years.<br /><br />The original spec. (from the original manual) suggested HD-30 (automotive). That stuff had as much lubricity as Bon Ami.

 

[oldboat1]

Re: synthetic oil and 1:24 mix engines.

Isn't it true that OMC stopped using babbit bearings after the 1956 model year? The '56 Evinrude Big Twin (30hp), for example, was prone to problems that the stronger '57 (35hp) didn't experience. I think the smaller post-'56 models also were less subject to bearing failure. Somebody can correct me on this.<br /><br />I'm not suggesting that you can safely go to a 50:1 mix, but I've found that a 24:1 mix with TCW-3 and contemporary plugs in my '57 Big Twin is just too rich an oil mix. I run about 40:1. Admittedly, I'm not out racing this engine.

 

[rolmops]

Re: synthetic oil and 1:24 mix engines.

Thank you all.<br />I did have my suspicions and you confirmed them.<br />I'll stick to TCW-3.<br />Oldboat are you suggesting that the '57 35 horse OMCs have needle bearings?<br /> <br />Glad to have this forum.

 

[oldboat1]

Re: synthetic oil and 1:24 mix engines.

can't carry the technical discussion re. bearings much further. It's my understanding, though, that there was a significant change beginning with the '57 model year. Again, I'm open to correction, but I think that the bearings used beginning in '57 were essentially the same as those in contemporary use. I thought that babbit bearings were the outmoded variety, but maybe my terminology is wrong. Synthetic vs. non-synthetic, of course, is a separate issue -- but the engineering change, if my sketchy history is right, may mean that pre-'57 motors are more subject to failure if the oil mix is too light.<br /><br />Actually, the information you received re. babbit bearings probably implies that those bearings are the contemporary variety, and that (perhaps)needle bearings were discontinued after '56 (?)

 

[Tracy Coleman]

Re: synthetic oil and 1:24 mix engines.

rolmops<br />'57 35hp have caged needle bearings as do '56 30hp, '55 25hp, 10hp, (not 3,51/2,71/2,12 and 15hp). 1950's 10's, 18's, 25, 30, 35, 40, 50, 1960 75, and so on. Heavy oil mix makes up for some of the absolute crap people used to use for oil for outboards. On babbit bearing engines some didn't have upper main seals, center main or bottom main seals, just a "slinger". Extra oil helps keep some crankcase pressure from leakage out top or bottom or swapping from cylinder to cylinder. And I have to vote nay on Steelespike's<br />comment on oil technology has not improved. Exxon's (was Esso) so called outboard oil in the 60's was so full sulpher, the sparkplugs would die of deposit accumulation long before they would burn out. I ran a 1955 Johnson 25 on 50/1 when the TC-W Johnson oil came out in 1964 for a service boat at our marina and skied a many a mile behind it. The 10 year old engine then was in a lot better shape then, than a worn out 1955 engine today. Went fishing today with my 1963 18hp Johnson now on a diet of Ram Ficht oil with Carb-X. There is a vast difference in oils. Pay me now or pay me later.<br />Backfire

 

[rolmops]

Re: synthetic oil and 1:24 mix engines.

Backfire.<br />Comments like these are like being sent back to school.<br />Thank you.

 

[oldboat1]

Re: synthetic oil and 1:24 mix engines.

Backfire -- Thanks on this end as well.

 

[Lark40]

Re: synthetic oil and 1:24 mix engines.

Backfire and Others -<br /><br />Were there mechanical differences between 1963 and 1964 J/E engines that caused OMC to change it's recommendation from 24:1 to 50:1?<br /><br />We had an Evinrude dealership back then and I recall the factory rep telling us about some improvement in the engine technology. Of course, that was a long time ago and I had more important things like girls and senior prom on my mind...<br /><br />But, was the change due to engineering improvements???

 

[Tracy Coleman]

Re: synthetic oil and 1:24 mix engines.

Lark40<br />The answer to your question, my view, no real difference between '63 and '64, it was the OIL.<br />Consider that the J & E 7 1/2hp, only made 3 years, was one of the best trolling motors ever. What I saw was in year round rental service, all at 24/1, after a whole lot of hours, usually a rod failure. Or the '59 35hp, a great engine, with a lot of hours, like a 1000 or more, the wrist pin bearings would give up and you would have needles hung in the ports or stuck in the head and piston, all on 24/1. The old engines up to the early '60s had overboard drains to drain the crankcase of unburned fuel. For several reasons not every drop of fuel goes all the way through the engine. In the crankcase, fuel was bled off and dumped in the exhaust housing under the powerhead. Some of this was pumped using crankcase pressure from the lower main to the upper main and another shot at going through the engine. +-Mid '60s overboard drains were eliminated. It all had to go through the cylinder.<br />Remember there was a lot of lead in the gas (and regular was 94 octane)! Lead also helps in the lube department. Actually engineers have gone to 250/1 in lab conditions on some engines. 50/1 is where you want to be on '64 and up, good shape engines, unless you are running RPMs above mfg rated levels, then it is 40/1 or less. Old worn iron pre '64, good oil at 30-40/1. I prefer engine mfg oils. I burn one or two gallons a year, how much can I save? how much can I loose!<br />My '55 25hp ran like a top at 2-300 more rpm on 50/1 Johnson oil back in the '60s. Engines were getting bigger, '64 90hp, 1 hp per cubic inch, good oil was needed now-TwoCyle-Water cooled.<br />Backfire