Remove the pistons? I've seen some videos were people don't remove them when cleaning with acetone. That was the purpose?

 

why would he have to remove the pistons? Couldnt he just rotate the assembly by hand and clean the cylinder walls with solvent while he does? Or i suppose oil would work too of course, just to make sure he cleaned up any carbon they may have fell to the side.

 

please update us on your oil consumption after having cleaned the piston.

my oil consumption doubled afterwards when my pistons were cleaned.

 

Jyeung528, when you cleaned your pistons did you have to remove them if the block?

Also so why do you think of the scratch and valves?

 

That piston scratch is cosmetic, just polish with fine sand paper to smooth it out. It is best to run a shop vac to pull all sanding dust.

Piston cleaning is not recommended, nor is it necessary. Any dirt and grit that get in the rings as a result of cleaning is going to sand the cylinder walls and cause oil burn.

In your pic the water jackets are taped up but the rings are wide open to cleaning debris. Do what ever you can to vacuum out any particles out of the rings.

 

^ that's why you shouldn't clean the pistons with them in the block and why I suggest they be removed and the bores cleaned now that the pistons have been cleaned.

 

Solvent will just re-distribute any dirt, gotta be hot soapy water and a clean rag. In this the service manual is not wrong.

 

Yeah I also haven't moved the pistons at all, what I will do is run the vacuum and re soak it with solvent as I move the pistons down applying the vaccum. I believe it should be fine. Others have cleaned them with no problems. My concern was that scratch.

 

Ditto, clean it up, see what it looks like. In the photo it just looks like the carbon scuffed off. But as mentioned, you'll want to use an abrasive to remove high spots as those high spots will create hot spots that could result in detonation. Looks totally salvageable though.