Ring Flush, how do you do it?

[kmyfm20s]

I have oily spark plugs on my #4 piston. 100hrs since engine was overhauled. Borescope looks fantastic with exception of oil pooling in the #4 cylinder. CHT and EGT haven't changed and are in line with the others. I hope to get a compression check this week. I have changed oil every 25hrs since overhaul and previous oil change was 1qt/12hrs and this oil change was 1qts/8hrs. I do have an air/oil separator. The oil looks good with a dark brown color and nothing in the oil filters. I did notice more oil on the belly of the plane since last oil change. I have a few rocker covers that started dripping since last oil change which could be contributing to the consumption and the belly. I have searched to find out how to do the "Ring Flush" but no real "How to's" out there. Another finding was baked oil around the exhaust slip joint of the #4 cylinder. I was thinking if the ring flush was no invasive that it would be something to consider. Any thoughts?

[N201MKTurbo]

I would just fly it for about 100 hours before I would worry about it. If the rings are still not seated, then I would talk to whoever did the overhaul and have them pull the cylinder and re-hone it.

[Guest]

Why not contact the overhauled for their opinion now? What is happening to the cylinder is not normal, I fear that you'll be removing the cylinder for repair sooner than later.

Clarence

[jetdriven]

To try to remove carbon from ring lands and free them, pour about 8oz marvel mystery oil into the top spark plug hole, then put the plug in and hydro lock the cylinder for 24 hr. Repeat for the others too. But from the pics I'd say the cylinder might be glazed and only a light hone and new rings will fix it.

[kmyfm20s]

Is the only way to fix a glazed cylinder pulling it and re honing it?

[kmyfm20s]

Also what does a glazed cylinder look like with a bore scope? Can you see it?

[robert7467]

I had the same problem. Run it full power on the takeoff and climb and run it 25/25 or 26/26. Basically don't baby it!

[stevesm20b]

I had the same problem on # 2 and 4 cylinders this month. I pulled cylinders off and found carbon buildup and stuck compression rings caused by excessive oil ring gap. Pulled # 1 Cylinder off last year, had broken oil ring. My engine has about 450 hours on it now. Don't think the person that originally did my cylinders when they overhauled my engine checked the ring end gaps. I took the cylinders to Corona Aircraft Engines at the Corona Airport (KAJO) for hone and install new rings. Cost was about $200.00 per cyl for the hone and re ring including gaskets. They did the work while I waited and watched. I'm happy with the work they did.    

[kmyfm20s]

Update. Took a nice cross country flight to Utah. Flew up and back running the engine at peak EGT. I was out of the red box since I was high enough. It looks like the problem resolved itself. I think the problem is with my normal flights to my office, they are to short and I'm not in cruise long enough. My routine flight profile looks more like skydiving operation since I fly from the coast over the coastal mountains to the desert, average 33 minutes. Note to self, more long trips:)

[M20TN_Driver]

This is an older topic, but I found it becuase I am going to be doing a ring flush on my Acclaim.  The Savvy procedure on how to do this is attached below.  I've never attempted anything like this and A&P on my field has heard of it, but never actually done it either.  

savvy-oil-control-ring-solvent-flush.pdf

[philiplane]

A ring flush is for older, high time engines that have carbon & lead built up in the oil ring drain slots. This usually happens well after 1000 hours in service, closer to 2000 hours actually. 

[ArtVandelay]

A ring flush is for older, high time engines that have carbon & lead built up in the oil ring drain slots. This usually happens well after 1000 hours in service, closer to 2000 hours actually. 

I assume this is only if you run ROP.

[Andy95W]

9 hours ago, philiplane said:

A ring flush is for older, high time engines that have carbon & lead built up in the oil ring drain slots. This usually happens well after 1000 hours in service, closer to 2000 hours actually. 

Not necessarily.  My #4 cylinder had a perpetual oily bottom spark plug starting at about 500 SMOH.  I did the ring flush using Marvel Mystery Oil.  It worked.  Two years later, the bottom plug still looks like all the rest.

It seems like a good thing to do to keep a small problem from becoming a large one.

[Greg Ellis]

6 hours ago, Andy95W said:

Not necessarily.  My #4 cylinder had a perpetual oily bottom spark plug starting at about 500 SMOH.  I did the ring flush using Marvel Mystery Oil.  It worked.  Two years later, the bottom plug still looks like all the rest.

It seems like a good thing to do to keep a small problem from becoming a large one.

If the Marvel Mystery oil was successful I think it would be a preferred method over using the flammable solvent mixture listed on the Savvy Oil flush on the file posted.  I am not sure I like the idea of using such a flammable mixture and then trying to dispose of it afterwards.  The warnings of not allowing it into the exhaust are kind of scary to me as well.  MMO is quite safe as it is used as both an oil and fuel additive, but is it just as effective as the Varsol/Xylene/Oil combo?

[N201MKTurbo]

27 minutes ago, Greg Ellis said:

If the Marvel Mystery oil was successful I think it would be a preferred method over using the flammable solvent mixture listed on the Savvy Oil flush on the file posted.  I am not sure I like the idea of using such a flammable mixture and then trying to dispose of it afterwards.  The warnings of not allowing it into the exhaust are kind of scary to me as well.  MMO is quite safe as it is used as both an oil and fuel additive, but is it just as effective as the Varsol/Xylene/Oil combo?

Considering that MMO is just oil and Varsol their mixture isn't much worse if any. I used to work with Xylene a lot. I burned it a few times. It is flammable, but nothing like gasoline. I even set it on fire at 70C, which was our working temperature. It makes a weak yellow flame. We used the xylene to dissolve wax out of tissue samples. The xylene burned much cleaner after it was saturated with paraffin.

Edited January 5, 2022 by N201MKTurbo

[CAV Ice]

On 1/4/2022 at 12:26 PM, M20TN_Driver said:

This is an older topic, but I found it becuase I am going to be doing a ring flush on my Acclaim.  The Savvy procedure on how to do this is attached below.  I've never attempted anything like this and A&P on my field has heard of it, but never actually done it either.  

savvy-oil-control-ring-solvent-flush.pdf 169.49 kB · 33 downloads

Doing this today on our Columbia 400.

[Greg Ellis]

1 hour ago, CAV Ice said:

Doing this today on our Columbia 400.

Post back how it goes for you.

[Andy95W]

4 hours ago, philip_g said:

My mechanic takes the cylinders off. Cleans everything grinds the valves hones the cylinders and reassembles with new rings 

That’s pretty invasive for a what is often a relatively minor issue.  It’d be akin to gastrointestinal surgery to cure an upset stomach.

But I appreciate his skill set.

[Andy95W]

12 hours ago, philip_g said:

The cracked ring became evident in a compression check 

 

That would have been useful information to include in your previous post.

[A64Pilot]

I have never done a “ring flush” and never expect to. I can’t imagine except for a rare case of it being the correct thing to do.

You have to ask yourself what’s happened to cause these rings to become so gummed up that they no longer function, and how will cleaning them out fix the problem? Meaning if nothings changed, how long will it be for them to become clogged again or worse happen?

Its just too easy on most aircraft to remove a cylinder, really only an hour or two’s work, and with it taken apart you can do an actual inspection and apply a corrective action, with a very few exceptions for me that’s been to send the cylinder for repair at an engine shop, the cost to hone a cylinder, fit new rings and replace the exhaust valve and possibly the valve guide has been between $300 and $400 in the past for me.

[carusoam]

On 1/4/2022 at 1:26 PM, M20TN_Driver said:

This is an older topic, but I found it becuase I am going to be doing a ring flush on my Acclaim.  The Savvy procedure on how to do this is attached below.  I've never attempted anything like this and A&P on my field has heard of it, but never actually done it either.  

savvy-oil-control-ring-solvent-flush.pdf 169.49 kB · 45 downloads

Not a very popular procedure to go through…

Can you give some detail about engine time, cylinder time, how you are operating the engine?

 

It would be helpful to know… if you are operating the engine in the go fast flaming dragon mode…

 

Some pilots wear cylinders out at the expense of going fast…

Often around here… dental cameras get used to take pics of the cylinder internals as part of figuring out what is going on…

See if you can supply some additional detail…

The topic may be older… everybody in the conversation is still here… 

Best regards,

-a-

[cujet]

Just an FYI, dissolving carbon is difficult. Few products will effectively soften or dissolve carbon. Consider what it takes to clean an oven! 

Berryman's B12 will slowly soften carbon and remove some kinds of paint. As a very general rule, it takes a product like oven cleaner or paint stripper with methylene chloride (the stuff that burns your skin) to effectively remove carbon. 

As much as we'd like to think Marvel Mystery Oil will do it, it won't. 

[jetdriven]

I haven’t had any success with the marvel mystery oil ring flush procedure, but I have had mixed results or limited results with using the paint can of Berrymans B12 chem tool. That stuff simply runs out the quick drain into the oil bucket with the rest of the oil. Gets disposed with it too. Other than that yeah, perhaps pull the jug and hone it. And I think they used to put bon-ami into the cylinder and run it thinking that would break the cylinder glaze.

[A64Pilot]

Way back when, maybe the 1930’s the P&W R-1340 had a procedure in the maintenance manual detailing how to use Bon-Ami to score the cylinder walls.

I’ve seen it in the manual but not done it of course, thought it interesting that it called out Bon-Ami by name

Today many scouring powders have chlorine in them, I have used scouring powder on the tip of a Phillips screwdriver, it helps on stuck screws,the trick is finding one without chlorine as that’s corrosive. Army mechanic trick, spit on the screwdriver tip and stick it into the scouring powder.

[cliffy]

14 minutes ago, A64Pilot said:

Way back when, maybe the 1930’s the P&W R-1340 had a procedure in the maintenance manual detailing how to use Bon-Ami to score the cylinder walls.

I’ve seen it in the manual but not done it of course, thought it interesting that it called out Bon-Ami by name

Today many scouring powders have chlorine in them, I have used scouring powder on the tip of a Phillips screwdriver, it helps on stuck screws,the trick is finding one without chlorine as that’s corrosive. Army mechanic trick, spit on the screwdriver tip and stick it into the scouring powder.

Dip it in fine valve grinding compound works better!