Carbon Deposit Removal

[L21-B]

Does anyone know the best way to remove internal carbon deposits from Lycoming cylinders, valves and pistons assuming they are removed from the engine.

[Chris Martyr]

Hi Jeffrey,
I'm sure that most traditionalists will tell you to soak them in Redex. That is the product that has always been used from the days when de-cokes were done about every 10,000 miles.

It is still available today but I don't know if it's been 'dumbed down' at all, what with all the H&S compliance and environmental considerations. Plus of course, modern day fuels and engines being so much more efficient.
A work colleague of mine swears that red aircraft hydraulic fluid [DTD585 or Mil-5606] is exactly the same stuff. It certainly has the same consistency and smell as Redex and it does remove carbon deposits as well.

[Ian Law]

Wish I'd known about this before spending weeks working my fingers to the bone trying with limited success to remove carbon deposits, without doing any damage. I ended up paying £100 to have the parts soda blasted, to get rid of the last remnants.

Ian

[tnowak]

I asked this question on another forum (across the big pond) and got these answers:

1. "Cylinder shops blast them with media"
2. "Worked in an engine shop 23 years ago and at that time we blasted them with a walnut shell media to remove the carbon so we could inspect the cylinder. Glass beads blasting before inspecting them was a no no in that shop. It was thought it could close up a tight crack and be missed during inspection"
3. "We used plastic media. The material removed from making holes on buttons"
4. "I don't know best, but I used Easy-Off oven cleaner"

Seems blasting with media is the preferred method.
Tony Nowak

[L21-B]

Thank you everyone for your replies, I will try and find a local source for media blasting, if unsuccessful will go down the route of soaking them in some kind of fluid, then will let you know what worked best.

[tnowak]

Jeffrey,

PM sent.

Tony

[L21-B]

Thank you just replied.

[Ian Law]

Or maybe this might be worth investigating?

....Vapor blast cabinet was set running today. For those who don't know, this is the Rolls Royce of blasting , ( used by many of the F1 teams) to clean components .It is very different to Sand or soda blasting ,as it uses fluid to encapsulate the medium, and uses flow rather than impact on the surface. As you can see ,we can leave steel studs , bolts in ,as there is no cross contamination and also we can blast across machined faces as it does not impact the surface. I am based in Okehampton , just along from LAS aero spares and will be starting work on the cleaning of parts from now on....

07429486692 Jack Jones & Co.

I have no connection other than coming across the link - and have no knowledge of the process.

[MikeM]

Ian, that was posted on the Devon Strut Facebook page by Strut member Richard Horner. We'll be following it up to assess its performance & suitability.