Piston soaking a 2 cycle outboard?

[Elkins45]

Let me add some background to explain why I‘m asking the question. Toyota’s main 2.4 liter engine in the mid 2000‘s was the 2AZ-FE. It was in the Camry, RAV4 and a bunch of Scions. In 2007 they made an engineering change and began using new pistons with low tension rings and what eventually proved to be undersized oil drain holes. After these engines got a bit varnished up the oil control rings stopped working and they became extreme oil burners.

I learned all this when I bought a used Scion xB and discovered it consumed over a quart of oil every 300 miles. In searching for a solution I learned than many people had success with pouring the cylinders full of Berryman’s B12 fuel system cleaner and letting it soak down through the rings. I tried it with mine and it reduced oil consumption to just a few ounces in 5000 miles, an almost complete cure.

So that’s the background that prompts this question: has anyone here ever tried something similar as preventative maintenance on a 2 cycle outboard? I have a 50 hp Yamaha three cylinder and I figured if I tilt it all the way up and park it pointing downhill I can get the piston tops pretty close to level, enough that I could give the rings a decent soak. I realize I might need to do one piston at a time to make sure the ports are covered so I”m not just pouring solvent straight through. Thoughts?

 

[Mc Tool]

I think that if you have been using good quality oil there would be no point .
I had a 2009 toyota with the 2azfe ,it had done 180,000kms when I wrote it off and didnt burn oil. I read about the oil burning issue and the drain holes bla bla bla , but near as I could tell it was only US peeps complaining ,

 

[Chris1956]

Trying to free up the rings on a 2 cycle motor is a standard procedure, when they stick. People soak 'em in all kinds of stuff.

It is not usually preventative maintenance, but a last ditch effort.

 

[Elkins45]

It is not usually preventative maintenance, but a last ditch effort.

The whole point of preventative maintenance is to avoid having to make a last ditch effort

 

[Chris1956]

True, but it doesn't apply to soaking the pistons to loosen the rings. The rings should not hang up. In your Toyota engine example, of course, you believe your rings hanging up is a defect in engine design. That is a different animal than preventative maintenance.

Preventative maintenance is doing thinks on a schedule to keep the engine running i.e. oil changes on 4 cycle engines, filter changes, spark plug changes etc.

If you want to do non-preventative maintenance things, that is fine. You might like to change your oil pan gasket every 2 years, just in case it starts leaking. That is not PM.

 

[Captain Caveman]

This is kind of like using the Atkins diet to stay in shape. The diet was created as a last-ditch effort to help morbidly obese people. I think this is Chris1956's point, that you may be using an extreme measure for perceived maintenance.

I guess that my question would be if there is a piston ring problem with 50hp Yahamas. If so, then maybe it is worth it. If not then I wouldn't do it.

All of that said, it probably won't ruin anything to do it but it may not do anything even if you do. If you start to have oil issues, then it might be an option.

 

[Chris1956]

In the particular case of stuck rings in a 2 cycle engine, I would expect the cause to be lack of use over long periods or water infiltration rusting the rings. The latter is not normal, and the former is unthinkable (smile).

 

[Scott Danforth]

Yamaha Ring Free is used often on 2-stroke motors that sit for loooonnnnnngggg periods of time.

some people use seafoam.

if you have stuck rings from carbon, it works.

if you have stuck rings from rust, it doesnt work.

 

[tphoyt]

This is bringing back memories of using Marvels Mystery Oil in my 65 Rivera.
A few weeks after that I broke a few rings and had to rebuild.

 

[DeepCMark58A]

Transmission fluid is another used to free up pistons and rings.

 

[Chris1956]

I am not sure I want to put transmission fluid in a 2 cycle motor. It will get into the crankcase and then be burned when you start it up. You will never be able to drain it all out, after use.

Marvel Mystery oil, Seafoam and Ring free are designed to be burned in a 2 cycle motors. I would stick with them.

 

[DeepCMark58A]

I am not sure I want to put transmission fluid in a 2 cycle motor. It will get into the crankcase and then be burned when you start it up. You will never be able to drain it all out, after use.

Marvel Mystery oil, Seafoam and Ring free are designed to be burned in a 2 cycle motors. I would stick with them.

Can't be as bad as people using starting fluid on a 2 stroke.

 

[Chris1956]

Yeah, I don't recommend that either, although there is usually a fair amount of residual 2 cycle oil from the engine flooding, to lubricate the ether.

 

[Scott Danforth]

Nothing wrong with ATF, or straight SAE 30

Years ago before 2-stroke oil, you mixed SAE30 with gas for 2-stroke motors

 

[Chris1956]

Scott, In the olden days, did anyone mix tranny fluid with gas for 2 cycle outboards? I expect the additive package would be bad for them. Tranny fluid damaged the paint on my '69 Marquis. 2 cycle oil would never do that.

 

[DeepCMark58A]

Don't spray and pray and you can suck out what doesn't leak thru and oil drain plug is pulled

 

[Mc Tool]

Scott, In the olden days, did anyone mix tranny fluid with gas for 2 cycle outboards? I expect the additive package would be bad for them. Tranny fluid damaged the paint on my '69 Marquis. 2 cycle oil would never do that.

50:50 trans fluid and acetone is a very good penetrant /solvent that has free'd many a stuck piston . A bit if trans fluid wont hurt the motor , and if your worried just crank it over with the spark plug out and it will blow most of it out . AND.....I know someone who once ran 4L of fuel mixed with trans fluid instead of 2 stroke oil thru his chainsaw without realising until he went to mix some more and saw the label one the oil bottle .
Why did you put trans fluid on your car....and did you actually try some 2 cycle oil too ?

 

[Scott Danforth]

Scott, In the olden days, did anyone mix tranny fluid with gas for 2 cycle outboards? I expect the additive package would be bad for them. Tranny fluid damaged the paint on my '69 Marquis. 2 cycle oil would never do that.

Dad and I have run chainsaws and outboards on ATF and gasoline. You mix it closer to 16:1 , where using SAE 30 is mixed closer to 24:1 and using SAE 40 is mixed closer to 40:1. Dad used to work in the test lab at Tecumseh. There were many oils tested over the years and run hard.

The biggest issue is carbon buildup, which can carbon up rings and exhaust spark arresters in chainsaws.

Are you sure it wasn't brake fluid that damaged the paint on your '69?