2 Stroke premix or not to premix?

WhyMe said:

The question was asked to me the other day why I haven’t got rid of Yamaha’s on board oil mixing system, and to premix it instead? I’ve always been told if it’s not broken why fix it.
I understand that if oil doesn’t get mix with the fuel the engine will be toast. So now the question is What would you do delete the Yamaha oil injection system or not.
I’m running twin 200 Yamaha 2-Stroke with the Greta stamp of approval.
Whyme

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I'm no mechanic at all, but aldeer had a discussion about this a few weeks ago and it was an overwhelming response to unhook and always premix.
Couple guys said theirs failed and when the motor alarm went off it was already to late

I have no plans to unhook mine. 2006 yamaha 90. I put a few hundred hours a year on it. If it fails, time for a 4 stroke!

KnottyBass said:

I'm no mechanic at all, but aldeer had a discussion about this a few weeks ago and it was an overwhelming response to unhook and always premix.
Couple guys said theirs failed and when the motor alarm went off it was already to late

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They guy that worked on my previous boat (which ran an old 90hp Johnson 2 stroke) essentially said this same thing - that the oil pump inevitably can fail and when it does, you may not know about it till the damage is already done.

The 50 Evinrude on my previous rig was deleted & so is the Yamaha 90 on my current one. I just feel better not having to worry about the pump failing.

I have a 1988 Japanese Yamaha that had oil injection. I removed it just to be safe even though it never failed. Anybody need one?

What is it less than 1 minute running WOT, by the time you realize the buzzer is going off, you dunnin monked up the motor. I know it doesn't take long at WOT w/o oil, sumpin's gonna f'up.....

Bought a 115 Yamaha for a barge. Opted to forego the pump and mix. Forgot that 2-smoke smell. Love it. And, at least I know it's getting oil. At the time, no 4-strokes were affordable or available. If I had it to do again, I'd go 4-stroke. We fish more out of the barge than we do putting out lime or fertilzer. Kind of like fishing off a skating rink.

One Outboard maker used the acronym VRO. I found out the hard way that meant Very Rapid Overhaul.

I see the group is leaning to premix. For those who have done this before. Delete the oil system what way is the best way?
Whyme

On a Johnson/Evinrude, delete it no doubt. On a Yamaha, I'd probably leave it.

oldflathead said:

One Outboard maker used the acronym VRO. I found out the hard way that meant Very Rapid Overhaul.

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I've always heard VRO as Very Rarely Oiled.
But either way, Overhaul will be in its future.

If you like to pull a plug trolling or just putt around, and you like to smell a very rich two stroke pull it. If you would rather have a cleaner exhaust and not look like a diesel while trolling, leave it. Don't forget if you plug a carburator while running it doesn't matter if you premix or not.

I was always afraid a Condom might Break so I never............ I was always afraid I might run over a Nail so I stayed Home.......I was afraid I might be Late for Work, So I Quit my Job...... I always was Afraid ........................................................................................................................ You Guys are Idiots............................. Oh Shit, Now I am afraid I Offended you Girls...............................................................................(Not Really...)


Leave the Dang Thing alone........................................

Running WOT and let a plastic bag garbage/ice/etc get caught on the water inlet jacket and you won't have to worry about removing the VRO or not. 😂🤣😂

I was waiting for the other side to chime in, and they didn’t let me down.

It's been years, but I used to have a Yamaha 115 2 stroke, I used old baby bottles, I'd pour a baby bottle of oil in the tank, then add the Gas, it got mixed in the tank as the new gas was going in, and while moving the boat. I never had any issues. Can't remember the ratio any more, but it worked for a long time till I sold it. Interesting discussion.

Decades ago, the Mercury mechanic (that was rebuilding my motor) told me that the commercial guys would pre-mix and not use the VRO.
I blew my Merc due a cracked, clear ($1.50) 4" hose between the pump to the mixing block (after the alarm). The motor locked up when I was running 50+mph, burnt 4 of 6 cylinders.
He said that "little hose" kept him in business.