The best way to soak and clean piston rings in your engine [SOLVED]

Thanks for the question Robert. Yes, it is safe to add Sea Foam through a spark plug hole. Mechanics have used this method for decades to free stuck rings and clogged expander rings. How to do it:  Remove the spark plugs and pour Sea Foam into each cylinder cavity through the plug hole. [Note that it’s easier to use Sea Foam Spray.]  Let the engine sit and soak up to 3 days (if you have the time). Be sure to crank the engine once a day to loosen the rings. You can also add a little more Sea Foam to each cylinder each day as it sits. Adding Sea Foam to the crankcase oil helps, too!

Last year I used Sea Foam in my ’81 Honda 500 Enduro after a cylinder lost compression. I let is soak for a few hours and my compression came back. Rode it all summer. It sat over the winter and lost compression again. Now I’m taking my time with it and letting it soak longer. After 24 hours it’s already working better! I’m going to give it a good multi-day soak, cranking the engine daily like Jim said. I expect that will at least get me through the summer. It’s good stuff. It works.

Great news, Brian. Sounds like you might have stuck rings. Can try Sea Foam Spray through the air intake, too!

I have an awesome engine, don’t want to lose it, rebuilt several years ago, alot of $ spent then, want to finish up now. I have already used pb40, any other suggestions, I have heard of atf working.

If you’re asking about what to use for soaking stuck rings, tough to beat Sea Foam Spray!

Is there a ideal temperature range to perform this procedure. I do not have a heated garage and it is winter here. Temps are ranging from the 60’s to the 20’s.

Hi August – that temperature range is fine.

Thanks.

Do you have to change the oil after soaking the cylinder?

It wouldn’t be necessary to change the engine oil, since not much Sea Foam is going to leak past the piston rings. (Note:
if your engine has problems with compression caused by stuck piston rings, it might be a good idea to change the oil anyways.)

I did the Sea Foam method for stuck rings. Any tricks for getting the little bit of the Sea Foam out of my cylinders before I put my plugs back in?

Hi Amber – to remove any remaining Sea Foam in the cylinders, turn the engine over without the spark plugs installed and let the Sea Foam “blow” out (may make a mess). If there is a lot of excessive product in the cylinders, probably best to get as much out as you can. Otherwise, no need to remove it, as the Sea Foam will simply burn up once the engine is started.

Carbon build up gets diluted, but how does it go out of the engine?

Hi Jul. Here’s what Richard, our tech director, said in response to your question: “Whatever contaminates get dissolved by the Sea Foam being in the cylinders will get burned up by the normal combustion process once the engine is started back up again(will smoke heavily for the first few minutes).”

Hey! I was wondering how many seconds I should spray sea foam into a cylinder before letting it soak for 24-72 hours.

Good question, Brian. You can spray for about 3 seconds in each cylinder.

One person asked how to get excess Sea Foam out of the cylinder before starting. My suggestion is turn the engine over by hand, using a breaker bar and socket on the crankcase bolt. After this, put the spark plugs in finger tight only, to cause some compression. The compression will push the Sea Foam into the rings, which is where you want it to go in the first place. Do this after the first 5 minutes of letting the Sea Foam soak into the rings. Then let it soak for another 30 minutes for the average car which runs ok to sluggish.
I do this every time I change spark plugs. For stuck rings, do the same procedure, but let it soak much longer before trying to turn the engine. Turn the breaker bar back and fourth slightly until you get easier movement. Then only turn in the normal operating direction.
After all the successful work, use top cylinder oil in the fuel on a regular basis, or add Sea Foam to the oil, which has some lubricant in it.

Thanks for the comment, Bill! One additional note: from a product formula perspective, you’ll want to let it soak for longer than 30 minutes (3 days even). That will give it time to get the most out of the Sea Foam.

Thanks again!

Using the liquid motor treatment instead of the spray, how much do you add to each cylinder?

I would recommend using about a 1/4 ounce of Sea Foam Motor Treatment or High Mileage per cylinder. If you have concerns that the piston rings are stuck to the cylinder walls, leave Sea Foam in each cylinder for 24-48 hours and attempt to turn over by hand before attempting to start the engine with the starter.

Any tips on trying this on a Subaru. Could it be added through the fuel injector port ?

Possibly. Guessing the reason that you want to use the injector port is because the injector port is on the top of the motor(easy to access) and the spark plug is on the side(very difficult to access). However, the injector port is on the back side of the intake valve on port fuel injection engines. Therefore, only one intake valve is open at a time. On GDI Subaru engines, 2019 and newer, yes it would work to introduce Sea Foam to the pistons. I’d suggest using Sea Foam Spray and going through the spark plug holes with Sea Foam Spray.

Thanks for this thread. Is there any importance of putting the cylinders in a certain position or does that not matter?

For example, all in the middle, or 2 in bottom dead center, then turning crankcase bolt until the other 2 are BDC.

I suppose cranking the engine every once in a while during the soak would have the effect of getting to the rings

If it matters, the car in question is a direct injection (MINI R55)

No particular position is needed though won’t hurt to try. Yes, cranking to move the pistons and rings is most important.

Can I use Sea Foam Deep Creep or need to be the standard Sea Foam engine treatment for this?

Yes you can. Sea Foam Spray (the aerosol version of Sea Foam) would be best, but Deep Creep would work as well.

Hello all, I just bought a 2007 motorcycle and put Sea Foam in through the spark plug holes…I tried using a turkey baster to remove the Sea Foam afterwards and I’m not able to draw any of it out… will it harm the engine if I just put the spark plugs back in and fire it up? Thanks!

Hi Jeff – I’d recommend turning the engine over slowly by hand or the kick-start lever slowly. But it also depends on the amount of Sea Foam in the cylinders. It has likely seeped past the rings and is now in the crankcase. I’d recommend changing the engine oil as well.

I have a Ford v10 that is locked up due to rust in the cylinders. Will the Deep Creep help freeing this motor up? I have used pb, free all, and atf/acetone mix. To no avail. It is out of the truck, and I am prepared to bring it down to a bare block and start over, but it only has 6k on it and I don’t wanna mess it up by rebuilding it especially as Ford uses TTY fasteners EVERYWHERE.

I recommend soaking the cylinders with Deep Creep. Apply Deep Creep liberally to all cylinder walls, concentrating on the ring grove area of the pistons. Let Deep Creep soak for 12-24 hours before attempting to rotate the crankshaft. Deep Creep should soak past the piston rings and end up in the oil pan area. Be sure to change the engine oil before reinstalling the engine and starting. 

If that does not work, you most likely have a stuck main or rod bearing causing your problems. And further disassembly would be required to determine cause. 

Hope that helps, and best wishes with the project!

I am purchasing a 1998 Cadillac Catera and the car has been sitting for a year. What should I do about the old gas that is currently in the tank?

The extra-cautious route would be to drain the fuel. Then, to use up the old fuel, you can occasionally add a couple gallons of the old stuff to 3/4 of a tank of fresh fuel.

That said, if it’s only been sitting a year, it should start and run fine on that old fuel. I’d drive it down until you’re at a low tank (1/8 tank or so), and then add a whole can of Sea Foam High Mileage. Then, run it until almost empty before refueling. The high concentration of Sea Foam will do a great job cleaning up any varnish that formed while the car sat. Hope that helps!

I have a 2014 Audi A4 that is burning oil. I have read it is probably due to the oil control ring that over many miles develops carbon buildup. I have added Sea Foam into my oil to hopefully overtime correct this issue.
Will adding Sea Foam through spark plug hole and letting it sit for a few days help this issue? Obviously oil rings are on the bottom of the ring pack. Will adding it to my gas tank help as this would continuously hit the pistons/cylinder walls? Thanks!

Hi Kyle,

Yes, adding Sea Foam through the spark plug hole and soaking it will help to clean things up. I recommend using Sea Foam Spray (which is simply the aerosol version of Sea Foam) through the spark plug hole and letting it sit for 10-12 hours. This will dramatically reduce the amount of residue built up on the piston rings. Sea Foam will “seep” past the compression rings and saturate the ring groves and oil control ring area.

In addition, a Sea Foam Spray Treatment through the throttle body can also help reduce build-up on piston rings.

And Sea Foam Motor Treatment or High Mileage in a strong concentration in fuel will always help get things clean. Add a full can to a low tank of fuel (1/8 tank or so) and drive until almost empty before refueling.

Hope that helps and don’t hesitate to let us know if you have any other questions or give us a call if you want to talk it through!

While soaking the top pistons as the carbon debris drips into the rings, can that run a risk of carbon chunks getting caught up again?

Any deposits that are re-liquified by Sea Foam are minimal size and will be encapsulated by Sea Foam, allowing them to ‘drain’ past the piston rings into the engine oil. This includes carbon, varnish, and gum residues.

When done properly, there is no risk of contaminating the piston rings. Sea Foam will clean the piston rings and ring groves in the pistons as well.

Just a note: once the engine is back running, be sure to change the engine oil and filter.