Piston ring cleaning?

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I've read that modern engines have the top ring higher on the piston. This was done to lessen the area for trapping the incoming fuel charge. Apparently this can result in the top ring being more prone to getting gummed up and not sealing well. Is there any reason to run a cleaner on my 81,000 mile Subaru engine? This engine has only seen Mobile 1 all its life? If I need to run a cleaner would those with experience suggest one for the gas or oil. Not really interested in the long drawn out 3 step/3x oil/filter system at this point in time. Opinions please. Thanks Ed Hayes
 
If you haven’t used any fuel systems cleaners in 81,000 miles, it’s time. I don’t know about your piston ring theory, but over 81,000 miles there is almost certainly carbon buildup on the pistons and CC’s, plus your injectors and intake valves could use a cleaning.

Without any information to back this up, I would think that a higher top ring would actually result in less build-up on the ring. If it were lower, the trapped, unburned fuel charge would seem to be a source for build-up. This is just how I picture it in my mind. What actually happens might be entirely different.

My current favorite fuel system cleaners are Redline SI-1 and Gumout Regane. There are many others. Get ‘em at your favorite local auto parts store and use as directed, e.g. add to tank (when parked next to the gas pump), fill it up, and drive until it’s almost empty again. Despite its stellar reputation, Techron doesn’t seem to work as well as the above. Fuel Power seems to be more of a maintenance product than a quick clean-up product. Some people recommend an oil change right afterwards (e.g. do it before your scheduled oil change) but the jury is still out on this one. If your rings are halfway decent, you should only get a minuscule amount of cleaner or byproduct of the cleaners in your oil. You get blowby in your oil all the time, are you worried about that?

Do you have reason to believe your rings are not sealing well? Bad compression or leakdown? Oil comsumption?
 
For oil control ring pack cleaning, consider using AutoRx.

Forget about MMO, 10-min flush(kerosene) and ATF (I'm 100% against that), use AutoRx instead.

Compression rings shouldn't be a problem so long as (a) you use fuel injector cleaner on a predetermined intervals; (b) your engine is properly tuned (no running rich/cold, bad O2 sensors, etc.) (c) no poor quality gasoline; (d) using something like FuelPower (e) air filter is capable of capturing abrasive dirts.

Compression rings require very little maintenance so long as the aforementioned conditions observed.
 
Eddie, DO you feel comfortable removeing your spark plugs? If so then you can get your pistons really clean doing a piston soak.If not then the next best thing is going to be spraying Amsoil Power Foam into your intake with the engine running. Periodic follow up with an intank cleaner like Redline SI-1, Amsoil Quick Shot etc.... will help to keep it clean!
 
2nd thing: RE: Subaru's boxer engine is notorious for varnish and oil pressure/oil related problems due to the engine design (horizontally-opposed). while it is generally a good idea to run the best quality motor oil possible so as to keep the internal mechanisms clean (synthetics/PAO or even a high quality GroupIII-IV blend works well, given reasonable OCI), it is still highly recommended that you should consider using something like AutoRx to clean the oil passages and maintain oil pressure.

As far as top piston ring's concerned, your observation is unfounded. Gumming (are you sure?) is never a problem in such as high-heat, thermally controlled combustion chamber.

You should be worrying about your oil pressure instead, IMHO.
 
Thanks for the replys: Yes I use techron concentrate fule system cleaner every 10,000 miles or so. Yes I do my own car service JohnBrowning so pulling plugs is no problem. You mentioned piston soaking with plugs out. What do you use for that? O-yes the engine runs great all the way to the red line on the rare occausions I do it. Thanks again. Ed O-yes, there have been several articules on ringpack sticking problems due to the higher ring placement. The Northstar engine is the one most often mentioned.
 
I’m not sure I’d do a piston soak in a boxer engine. The piston top is vertical and the cylinder is horizontal. All the solvent would flow to the “bottom” of the cylinder and not coat the top of the piston or the combustion chamber. I suspect a substantial amount of solvent would soak past the rings and into the oil.
 
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