Can merc powertune soak inside engine for a few days trying to free stuck rings ??

[baddjonny]

Don't know how strong it really is don't want it eating gaskets , seals etc. I know it works good , engine I'm working on sat for 5 years outside , old owner claims compression was good and even when put away (the last great words of a outboard salesmen)now the cylinders around 90-100 on #5-6,on #3-4 30-40 and #1-2 20-30 tried pb nutbuster in #4 without letting it sit , it jumped to 50-70 should I play it safe and use pb nutbuster or blast it with merc powertune. Of course I' trying to avoid pulling the heads so I can at least try to start motor on the hose to see if I have a bag of bolts or not . Funds are very tight so I'll have to go in small steps it's a 91 225 omc looper I bought for $400 from craigslist.

Thanks as usual
jon b

[sschefer]

Jon, remember that a motor that sat that long won't have a lot of lube in the cylinders. Rings don't seat like is commonly thought, they seal. The thin layer of oil between the cylinder and the rings is the seal. On a motor that's been stored for a long time, I recommend using a fogging oil and cranking the motor over by hand for a while. Once you've got her lubed up again the compression should come up a little but sticky rings will need a little more persuasion. It should start even with sticky rings so I'd run it on 2 gals of at least 90 octane fuel, 40:1 premixand 1 can of SeaFoam. Run it for 15 minutes, soak it for 30, then run it again. I recommend you do this until the 2 gals of fuel is gone.

After that, start it up on another 2 gals of premix at 50:1 and when all the smoke clears your engine should be running as good as its going to for the time being. You'll probably need to do more work but sometimes this is all it needs to get it running.

Hope this helps..

Regards,

[Bruster]

I had a newer 25 Johnson that had rings that were carboned tight in to the pistons. The motor did not have enough compression to start, otherwise the motor really appeared to be in good condition otherwise. I have no idea what they were using for oil. I pulled the cylinder head and exhaust cover and soaked the pistons with engine cleaner for a week. After the rings came free It started and I ran it for a couple hours in a tank at about 2000 RPM. Compression was normal and it ran (and still does) like a champ.

[cranknrods]

i use atf, it wont hurt seals and seams to do a pretty good job of loosening things up. i keep an old spray bottle filled with atf for those times when metal to metal seizure happens. its not as strong as some of the other things you could use but it does seem to work. understand i come from the 4-stroke diesel world so if this is bad on a 2stroke outboard sombody please let me know cause i kinda do it often enough to matter. thanks

[Bies]

If they are really stuck look at KANO labs and kroil the crap out of it, keep it wet,
I have broken loose some Chri-Craft engines that people said I couldn't get to run.
$20.00 and case of beer bet, that beer was sure cold.
Good luck

[typhoon]

I like plain old 2 stroke oil, put it on an oil can and soak the crap out of all the cylinders through the plug holes and drown the front of the engine with it through the carbs.
Crank the engine over with all that oil in it (plugs out) and let it sit a few days. Any oil will help dissolve any crud in there and 2 stroke oil is meant to be there and will burn off more easily when you fire it up.

Regards, Andrew.

[baddjonny]

It's amazing all of everyone's pet freeing up techniks for stuck engine parts. I'm suprised know one is still useing marvel mystery oil always great stuf when I used it as a additive don't know what it really is but it also worked good. Getting back to original question will powertune eat up gaskets and seals if left in for a few days. ??
jon b

[albypine]

sitting that long out side does more harm then good.. i have seen car motors in junk yards that sat for 20 years that were froze up and would not turn over by hand .. filled cylinders up with atf or marval mystery oil and it did free up the rings enough to make em run, but with out pulling the heads you will not know if the cylinders have bad rust pits, or if the gaskets are going to fail from age.if you had a bore scope would give you a better idea of how the cylinder walls look. pb blaster does work great, but dont know what it will do to the gaskets.oxidation makes it fun when you try to pull the head bolts and they start breaking off. good luck

[Bies]

I have not used powertune, but I would think it would be in the same class as Chemtool
Chemtool is good for minimal exposure, I have seen it swell o'rings after long exposure.
It falls into the chloranated solvent realm, I would be careful, pour some in a cup and leave some material gasket ect. and see the effects before long exposure to the complete engine.
Let me know what you find out.

[baddjonny]

Reading merc powertune can contains aromatic petroleum cas , butoxyethanol cas , propane cas , petroleum oil cas and morpholine cas . Don't know what most of those chemicals are but I do know if you get a wiff of the exhaust after puttin it in , hold on to something it will gag you for sure . I think I'm going to play it safe and soak it with pb nutbuster then try starting on the hose and run 1 or 2 gallons of gas through it with pennzoil at around 36 to 1 . For the money I paid for it $400 I'll take a shot running it on the hose.
Man what nasty sounding chemicals are in that powertune stuff. Any one know what the difference between petroleum oil and aromatic petroleum is??

jon b

[Forkin' Crazy]

I have not used powertune, but I would think it would be in the same class as Chemtool
Chemtool is good for minimal exposure, I have seen it swell o'rings after long exposure.
It falls into the chloranated solvent realm, I would be careful, pour some in a cup and leave some material gasket ect. and see the effects before long exposure to the complete engine.
Let me know what you find out.

You talking about B12? I don't use that on two strokes at all. Powertune and Enginetune (Merc/BRP) will not hurt gaskets or seals. I love the stuff and often use it to lube rubber cannon plugs, etc too.