Piston Soak

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Has anyone done a piston soak with straight gasoline? (Pics of this?)

It's a solvent by nature and a runny liquid and I'm sure it would release carbon and gunk from the piston tops and rings?

Just a thought...
 
I know it would wash the cylinder walls but in general it might be a better soak for engines and we could over come the washed cylinder walls after the treatment using some like Napa type oil in the cylinders after like Seafoam or Lucas or whatever until natural lubrication is restored by the oiling system in the engine.
 
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StevieC, what I like about your idea is that since the soak is getting blasted out of the open spark plug holes anyways, it may not do any harm. I've piston-soaked with other fluids, even a mix of, so I'm asking what other adverse affects plain gasoline could have.

Piston soaks are best done with warmed chemical on a hot engine, so that wouldn't bode well for gasoline, unless perhaps it was left in until the engine was cold.

Any other opinions on this?
 
As engines have "clear flood" modes where depressing the accelerator to the floor while cranking causes the ECU to turn off the injectors while cranking I can't see how excessive gas would cause a problem other than washing the walls and rings of lubrication which can be remedied as I described above if really concerned sort of thing. What I'm getting at is this excessive fuel in the cylinders could exist under real world conditions. Albeit not a lake of fuel but enough to wash the walls if the engine was flooded.

You could run the engine until it's warm, let it cool slightly and then fill the cylinders with fuel and put the spark plugs back in to stop evaporation. Then take them back out and crank over to rid the cylinder of excess fuel that is left.

The more I talk about this the more I think this might be a good idea for carbon. I just wish I had a carbon-upped engine to test it on but I don't at the moment. I do have a boroscope so I could record before/after pics.
 
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This is a pretty basic operation.
It's less wasteful to soak with a crankcase full of old, ready-to-change oil (since you'll be contaminating it).
Pick a solvent and send it down the spark plug holes.
Wait.
Crank the engine to move it a bit. If I was doing it I'd put a socket on the crank pulley bolt and move the engine 5 degrees each way repeatedly.
Maybe denatured alcohol or lacquer thinner would work well.

What "adverse effects"?
Your engine will relube itself.

After a soak, I'd start the engine for 10 seconds then drain the old, now-contaminated oil and change the oil and filter. Done
 
And run a UOA on the old oil and watch the heads spin.
lol.gif
 
Seems there isn't a really healthy way of going about it with before / after sparkling results and before / after UOA showing no increased engine wear as a result.
 
Originally Posted By: StevieC
As engines have "clear flood" modes where depressing the accelerator to the floor while cranking causes the ECU to turn off the injectors while cranking I can't see how excessive gas would cause a problem other than washing the walls and rings of lubrication which can be remedied as I described above if really concerned sort of thing. What I'm getting at is this excessive fuel in the cylinders could exist under real world conditions. Albeit not a lake of fuel but enough to wash the walls if the engine was flooded.

You could run the engine until it's warm, let it cool slightly and then fill the cylinders with fuel and put the spark plugs back in to stop evaporation. Then take them back out and crank over to rid the cylinder of excess fuel that is left.

The more I talk about this the more I think this might be a good idea for carbon. I just wish I had a carbon-upped engine to test it on but I don't at the moment. I do have a boroscope so I could record before/after pics.



I would guinea-pig that!
 
Why not mix Seafoam or just some engine oil with the gas ? Or even 2 cycle oil ?

Hope I am never in need of such a treatment .

I agree , do this right before you change oil / filter .

Best of luck , :)
 
Originally Posted By: LaCocina27
Originally Posted By: StevieC
Do you have a Boroscope to take pictures/video before/after to share here?


I do not.
frown.gif



Darn, no way to measure the results...
frown.gif
 
Originally Posted By: WyrTwister
Why not mix Seafoam or just some engine oil with the gas ? Or even 2 cycle oil ?

Hope I am never in need of such a treatment .

I agree , do this right before you change oil / filter .

Best of luck , :)


Ihink that might take away from the solvent action IMO.
 
Originally Posted By: StevieC
Originally Posted By: LaCocina27
Originally Posted By: StevieC
Do you have a Boroscope to take pictures/video before/after to share here?


I do not.
frown.gif



Darn, no way to measure the results...
frown.gif



I don't think the seat-of-the-pants test is total bunk.

Though, the smoke show could also be problematic!
 
I'd think that gas is volatile enough that even a good quantity of it would evaporate out before it did any good.

As well as volatile, it is obviously VERY thin, so wouldn't it run past the cylinder rings almost as fast as it went it?

If gas stayed in the cylinder at all, then hard-to-start engines would hydro-lock all the time, but they don't - the plugs just get wet enough not to fire for a bit.

You need something that is 'oily' enough that it will stay around a bit.
 
Originally Posted By: addyguy
I'd think that gas is volatile enough that even a good quantity of it would evaporate out before it did any good.

As well as volatile, it is obviously VERY thin, so wouldn't it run past the cylinder rings almost as fast as it went it?

If gas stayed in the cylinder at all, then hard-to-start engines would hydro-lock all the time, but they don't - the plugs just get wet enough not to fire for a bit.

You need something that is 'oily' enough that it will stay around a bit.


The way I know it would stick around a bit is a friend of mine hydro-locked his engine with a bad carbeurator and it took me 30 minutes to get to his house plus diagnosis time to figure out what the problem was. We took the plugs out at about the 1 hour point and cranked over the engine and what seemed like buckets of fuel sprayed out of the spark plug holes on a few cylinders.

grin2.gif
 
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After you pulled the plugs & blew out the gas , was the engine permanently damaged ?

thanks , :)
 
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Originally Posted By: WyrTwister
After you pulled the plugs & blew out the gas , was the engine permanently damaged ?

thanks , :)


No, and I think it was because it was not an interference engine. I have seen Asian 4 cylinder hydro-locked and they have either a bent valve stem or broken rings.
 
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