Author Topic: Any tips for cleaning carbon off pistons?  (Read 1053 times)

Offline Matt_Harrington

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Any tips for cleaning carbon off pistons?
« on: June 19, 2023, 06:52:51 PM »
I now have certain items off being cleaned and painted and thought about cleaning up the pistons I am going to use. Anyone got a tip that worked?  A magic dip they used?  ;)
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Offline Nurse Julie

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Re: Any tips for cleaning carbon off pistons?
« Reply #1 on: June 19, 2023, 07:15:09 PM »
Soaking in Cellulose thinners works well.
« Last Edit: June 19, 2023, 07:16:57 PM by Nurse Julie »
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Offline McCabe-Thiele (Ted)

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Re: Any tips for cleaning carbon off pistons?
« Reply #2 on: June 19, 2023, 08:02:31 PM »
I am not aware of any solvent that will remove carbon deposit as it's pretty much insoluble in my experience.  Chemicals that attack carbon will usually eat through aluminium a treat. Oven cleaners are based on caustic soda that will damage aluminium.
Acetone can soften light deposits if they are petro-carbon based probably clean the lower sides of a piston but not the crown. .
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Offline Oddjob

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Re: Any tips for cleaning carbon off pistons?
« Reply #3 on: June 19, 2023, 08:25:39 PM »
Use the abrasive brushes that Roo uses Matt. Start off with light blue and see if that removes it, if not go up to red and try that. Finish off with light green and it should gleam afterwards.
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Offline Matt_Harrington

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Re: Any tips for cleaning carbon off pistons?
« Reply #4 on: June 20, 2023, 06:28:31 AM »
Soaking in Cellulose thinners works well.
Julie, I had forgotten about that and have used that in the distant past.

Use the abrasive brushes that Roo uses Matt. Start off with light blue and see if that removes it, if not go up to red and try that. Finish off with light green and it should gleam afterwards.
Yes, that is an idea.....
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Offline Sesman

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Re: Any tips for cleaning carbon off pistons?
« Reply #5 on: June 20, 2023, 08:45:33 AM »
I used thinners then 20 mins in the ultrasonic tank @ 50deg and they came up like new.

Offline McCabe-Thiele (Ted)

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Re: Any tips for cleaning carbon off pistons?
« Reply #6 on: June 20, 2023, 09:05:43 AM »
Did you use thinners in the ultrasound bath by putting the piston in a jar or just normal cleaning fluid for the last stage Phil?
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Offline Laverdaroo

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Re: Any tips for cleaning carbon off pistons?
« Reply #7 on: June 20, 2023, 01:35:47 PM »
Bob it in a jar Ted and place the jar in the warm bath of the ultrasonic. You won’t need much thinners then and or have to bear the tank smell of the stuff, it’s vile!.

I had mixed results with cellulose thinners and resorted to the Dremel brushes that Ken mentioned on one set. Came out like new but depends how crusty yours are buddy.


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Offline Sesman

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Re: Any tips for cleaning carbon off pistons?
« Reply #8 on: June 20, 2023, 03:20:18 PM »
Hi, Ted. Thinners and nylon brush. Yes, I used a strong solution of Allendales best in the US cleaner.

Offline McCabe-Thiele (Ted)

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Re: Any tips for cleaning carbon off pistons?
« Reply #9 on: June 20, 2023, 03:32:59 PM »
Hi, Ted. Thinners and nylon brush. Yes, I used a strong solution of Allendales best in the US cleaner.

Every day is a School Day - I could not envisage Thinners as a Carbon Solvent (or any other solvent) - I guess it must break down the petro-carbon bonds between the soot type particles.

Might be an easy way to de-carbon a cylinder head  & valves instead of all that brushing & scraping. 8) 8) 8)
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Offline McCabe-Thiele (Ted)

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Re: Any tips for cleaning carbon off pistons?
« Reply #10 on: August 14, 2023, 03:58:43 PM »
Just an update on Julies & others post absout using thinners to help remove carbon deposits.

Today I tried it on my cylinder head, I was stunned at how effective it was, tbh I was a none believer - now I have seen the light. 

I used a stiff circular brush inside the exhaust ports from the manifold end, after two or three applications with a bit of swirling of the brush clean aluminum started to appear! I finished off using a small soft brushing wheel in my drill.
Less effective on the exhaust valves so resorted to putting them in a drill using a Stanley knife blade as the cutting edge against the carbon deposits.





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Offline Pauarc

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Re: Any tips for cleaning carbon off pistons?
« Reply #11 on: August 14, 2023, 04:41:43 PM »
I used a dishwasher tablet in a ultrasound bath they came out pretty clean
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Offline McCabe-Thiele (Ted)

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Re: Any tips for cleaning carbon off pistons?
« Reply #12 on: August 14, 2023, 06:36:22 PM »
I used a dishwasher tablet in a ultrasound bath they came out pretty clean

Was that on the valves?
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