fuel mix for old Johnson

I am new to this site, hoping for some help. I recently acquired a 1962 Johnson Seahorse 5.5. Runs great, needs a couple of lower end parts which I have a line on, but I have conflicting info on the fuel and oil mix. Is it 50:1 or 25:1? Don't want to burn it up.

Thanks

 

25:1 it is.

 

At first, reading the title, I thought the "fuel" might be ******, but now I see... Yes... and seriously, the question is, are the new 50:1 ratios more related to improvements in oils? If so, then maybe the newer 50:1 ratios might apply?

 

Not sure if a newer 2 stroke oil would allow for a leaner mix like 50:1. But I am sure that the pre 1970 something engines asked all for 25:1.

 

I think the new 50:1 ratios are also related to improvements in bearings. So personally, I wouldn't trust my luck with a motor that old.

I'm getting ready to fire up an old Elgin 2 1/2 hp sometime today (as soon as work stops getting in the way...). The owner's manual calls for '3/4 pint oil with one gallon of gasoline,' which is about ten:1. It does say that 'for continual slow-speed operation, 1/2 pint to a gallon is acceptable.' That's 16:1....

I know oils have improved. But I also know my little Elgin has bronze bushings for bearings, so I think I'll stick with 16:1....

 

Okay... I shouldn't have written the name of an erectile dysfunction drug that sounds like a famous waterfall. Just now noticed the stars. So to get the humor intended, replace ****** with that famous drug.

 

Few engines have plain bearings nowadays. I'd guess you're right that they might need more lubrication. Other than that, most ball, needle, and roller bearings are many many decades old in design.

 

Thanks, I think. I still have 2 answers, same as the info I had before, but I am going to go with 25:1.

 

Even newer motors call for a richer oil ratio for the break-in period. Better too rich than too lean.

 

You're right; my Elgin with bronze bushings instead of bearings is an extreme example. But I'd say modern ball, needle and roller bearings are made of better materials than they were fifty years ago.

On the other hand, there's also the fact that way back when, they didn't have oils formulated specifically for 2 stroke mixes. For example, my Elgin's manual calls for ordinary motor oil, so using modern oils would probably let me get away with a lot leaner mix. On the other hand, it's probably older than I am - and looks to be in better shape. It would be a shame to burn it up because I was too chintzy to pay for oil....

I hope no one assumes those old engines can run just fine on regular motor oil, just because they did way back when. Regular motor oil in those days didn't have detergents, or a slew of other additives. Today, it's probably much safer to stick with the 2-stroke oils.

 

I'm not sure if the old 5 had a bushed small end but oils are way better now then then.
Both changes happened to engines, bearings got better and so has the oil

 

Agree, both got better. But better sometimes does not include good.

A synth. oil in a 1962 Jaguar 6cyl. will quickly provide you first hand knowledge about the actual engine prices.

The better bearings are most likely not installed in the engine in question, so, mute to discuss.

I even doubt the engine will do any better with a high tech 2stroke oil of today, and I´m sure a lean mix kills her.

Regards
Richard

 

This is a 2 stroke not a 4 stroke.
The oils today are made for the fuels of today.
They burn way cleaner so there are little to no carbon deposits left in the engines. De coking was something that was done to old 2 strokes but not any more.
When there was no spec for 2 stroke oil, people used plenty and as the oil gained a spec and got better ( BIA-TCW 1, 2, and now 3) engines used less and less.
The only difference in the bearings was big ends went from crowded to caged and small ends went from bushed to roller (in small engines)
( Some 2 to 4hp had bushed big ends as well as late as mid 80's but all ran on 50:1)

Old 4 strokes have problems with new oils as many compnents have been removed for emission rules and old flat tappet cam followers etc. suffer due to the zinc being removed, not to mention friction modifiers that old style ring/bore finishes cannot deal with it.

EDIT> I just spoke with BRP OZ and for OMC engines they said if the original spec was 25:1 then TCW3 at 50:1 is the way to go.
TCW 3 included these old engines (1960's) in the oil spec.
Other brands that had specs of 10-15:1 etc due to non roller big and small ends are a different story

 

http://www.youtube.com/watch?v=fxVH5sKUlPg

 

Its not easy being Green.

Hey your in Hamilton?

I gave away an old Johnson 5.5 to a guy I worked with at DEC years ago. Maybe it might be you? It was not the traditional Johnson Green nor the transitional Johnson Red but the new wizzbang traditional Johnson White.


It takes a 30:1 ratio. Mix 1 Quart Quaker State ( Nothing is better for thee) into a 5 gallon can of High TEst or Ethal Leaded Gasoline ( Ah Ha! Now you have a dilemia I can tell)


directions are on the back of the can. Open with a churchKey