Re: 1970 evinrude 4hp lightwin
Can I follow up on what I said before I lose ALL my friends? There is great controversy concerning oil mix, especially where an engine uses bushings instead of roller bearings. And the "more oil is better" group is in the majority.
As I said, 50:1 was specified by the factory. And as many will testify, more oil won't hurt anything and might even offer some extra protection. And it might last longer too. On the other hand there are thousands of those things surviving just fine on 50:1. Balancing the scale are those that are worn out or have self destructed.
Personally, I think a lot of those worn out motors either have a jillion hours on them, or have suffered some sort of trauma such as water ingestion where it doesn't belong, or overheating--the two single biggest killers of any outboard. But there again, extra oil may have saved it, offsetting the trauma damage.
Some were just plain poorly designed with inadequate materials, inadequate seals, etc, etc..
And the ones that run poorly on up to 24:1 probably have contributing factors such a poor ignition, wear, or other things. Finally, some run lousy now because they ran lousy when they were new. There were some poorly designed motors out there y'know. There were some that you had to take your toolbox along on every trip too.
So what would I do if it were my motor? That is easy to answer---I run all my old motors on 24:1, using high quality TC-W3 oil, mostly synthetic to help the environment. But the largest motor I have at the moment is 5hp, except my 1984 35hp, which gets 50:1
Summing up, if you have read all this, you understand what I meant when I said "Your Choice". It is also why I don't give oil mix advice. At least not in public. I slipped up this time, and will try not to let it happen again. Till next time.
Now, can we talk about something less controversial like politics or sexual preferences? NO, PLEASE!!!