Active ingredients in carbon deposit solvent

  • #1
TL;DR Summary
Identifying the active ingredients in a carbon deposit solvent
I'm looking at berryman's b12 chemtool.
It is used with success to remove carbon deposit on piston rings, breaking them free from sticky sludge, and thereby lessen oil consumption.
I can not get the product where I live. So I wonder if I could copy the effect by identifying the most lightly active ingredients and make a blend?

The content is and the numbers are percent, I think volume percent.
Toluene 40 - 50
Acetone 20 - 25
Methanol 20 - 25
Methyl Ethyl Ketone 1 - 5
2-Butoxyethanol 1 - 5
2-Propanol 1 - 5

Toluene is a constituent in gasoline. I'm not sure, but I think it might act more as a carrier for the active ingredients and basically safe for the combustion chamber where you pour it down the spark plug holes. If so could I use gasoline instead?
I wonder about the last 3 ingredients, do you think they have a big impact if omitted?
Why I ask is because they are hard to get.
I know that gunsmiths use 2-butanone (MEK) to clean carbon deposits in guns.
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  • #2
Welcome to PF.

hajonnes said:
I can not get the product where I live.
With my Mentor superpowers, I'm able to see your location, and it's not like you are in the middle of a desert or something. When you ask about similar cleaners at your local auto parts store, what do they recommend?


  • #3
Thank you :)
There have been multiple discussions about getting it and alternatives on forums. There is no product in Europe that is comparable according to the posts. It is only available in USA. Since toluene, methanol with 5% nitromethane and acetone is redaly available I wanted to get an opinion on the viability of using a blend of these. I omitted the nitromethane since it will be low concentrations reading more about it, it is used in solvents for ca-glues and might not be good if it reaches the hydrocarbons in the piston rings. On the other hand it is low concentrations and I will change the oil after the procedure.
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  • #4
hajonnes said:
It is used with success to remove carbon deposit on piston rings, breaking them free from sticky sludge, and thereby lessen oil consumption.
Clean oil can be a good solvent for gunked up piston rings. Try changing the oil, then do a two hour highway drive at the highest practical speed. If the oil gets dark in that time, the hot oil is acting as a solvent and removing deposits. The solution would then involve changing the oil more often.

A long time ago, I bought a car for temporary transportation. The seller claimed that oil changes were not needed because it used so much oil that it changed itself. It started well, ran well, got good gas mileage, but only got 90 miles to the quart of oil.

So I changed the oil. The new oil turned black after driving less than 10 miles. So, for grins and giggles, and to find what would happen, I started changing oil after it was down the second quart. It went slightly farther between each oil change. Four year later, it was getting over 900 miles to the quart of oil. I paid $60 for that car, and sold it for $100. Four years with negative depreciation was not bad.
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  • #5
Interesting. That path is doable, but the cost of an oil change here if you do it yourself is about $60, with a good oil and filter, and you will have to do a lot of them. But if labour and price where no problem I think that method is the best. There is even a special oil that is made for cleaning, Valvoline restore and protect. But I do not know if it is better than any other premium oils. I was thinking of giving the car a bump in the right direction and be nice to it with oil changes from now on.
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  • #6
Laquer thinner.
  • #7
Some decades ago, when I bought my first car from a neighbor, my father noticed that regular oil changes had not happened to it. Also, it had been sitting unused for over a year.

His suggestion was run it long enough to warm up, drain the oil, replace the filter, refill with kerosene.

Start it up at idle speed only, and run it just long enough to circulate the kerosene.

Drain the kerosene, replace the filter, and fill with oil.

If I recall correctly, I got about a year of life out of that car.

HOWEVER, I am not saying the cleaning method was the best possible one!
  • #8
There is a published procedure for solvent flushing aircraft engines with gunked up piston rings: Aircraft engines still use leaded fuel, so piston ring deposits can be either carbon, lead residue, or both. Piston ring deposits show up as low compression and/or high oil consumption.

Tom.G said:
His suggestion was run it long enough to warm up, drain the oil, replace the filter, refill with kerosene.
This scares me because it removes the oil film from the cam lobes. Any disruption of lubrication can cause scoring of the cam lobe, which can progress to total failure of that cam lobe even if lubrication has been restored.
  • #9
I will try to free up the carbon/polymerized oils on the rings using the mixture with methanol, acetone and toluene.

About methanol:
I tried to dissolve some paint on plastic. The methanol- nitro methane blend could dissolve the paint half as good as acetone where as ethanol did not dissolve anything by rubbing a soaked rag against it.
I can not get pure methanol and was wrong about the mixture in the methanol. It is RC fuel and have 17% castor oil, 16% nitro methane and the rest methanol. Do any of you see any problem with that blend?

@jrmichler Very interesting instructions. What would you use for the spraying of relubricant down the spark plugs holes? I was thinking that for a car I would save the oil and not change the filter. Then I would refill with old oil and run the car for a couple of minutes to rinse out all solvents. Then make an oil and filter change. What do you think?

To find the compression stroke use a compression measurements tool and unscrew the gauge and fit a balloon. When the balloon inflates it is a compression stroke. Credit: youtube
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  • #10
I wanted to give you an update on the progress.
I mixed paint thinner (toluene) and RC-fuel (methanol) with acetone at a ratio of 120ml paint thinner, 45ml RC-fuel, 24ml acetone (there where some in the paint thinner). To get the approximate ratio of Berryman's.
I poured it down the spark plug holes in the the beginning of the compression stroke, fitted the spark plug and compressed. I let it sit with static pistons for 48h and top up multiple times. Then sucked it up with a syringe fitted to a longer small diameter hose. The hose length will determine how much you can extract from the cylinder. Let the solution only enter the hose not the syringe because the solution will render the syringe broken.

What was not so good.
A plastic sensor in the sump got affected, probably because it was partly melted by the solution. After running the car some time it started working again.
There where not much lubrication during the hydrolock compressions. I might have marred the bearings.

If I would do it again I would have kept the oil in the motor, it would have contaminated the motor oil but I would have done an oil change afterwards anyways. That would have negated the possible marring and the effect on the sensor.

What was good.
Afterwards the car felt like a different beast entirely. It ran so much better.
It had torque in low rpm that it did not have before and was much more agile.

I would definitely do it again if I had the same problem again.
I would have just poured in the solution and perhaps agitated the crank a little and let it sit and top up. When agitating some claims the timing belt can jump a notch if you do it in the opposite direction of how the motor spins. For me nothing happened but it might be best not to. Not try to hydrolock it with the solution to force it past the piston rings. Perhaps let it sit for longer since less mechanical agitation was applied.

A note. The car did not want to start afterwards. I had to connect it with starter cables to a second battery to let it rinse out the solution before it started again. Even if I sucked most of solution out. It took quite a lot of Ah from the both batteries. If anyone tries this have two batteries that are fully charged at hand. I let it rev for between 2000-3000 rpm for 10 minutes to clean out everything after start, then I did an oil change. The oil that came out was smelling like the solution.
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