top of piston

[Neptune]

I changed my pcv valve today on my 2004 vibe and decided to remove a plug and see what the piston tops look like. I actually only looked at one. It was somewhat dark looking. No shiny metal suface showing. I quess there was a light layer of carbon build up. I have used Techron and Regane (either/or) at 6 month intervals in the past and I most recently used about 5 oz. of mmo in the gas tank. I also use primarily Exxon gas. I expected the piston tops to be much cleaner looking. This is with 81,xxx miles on the clock. I just changed the oil and filter today as well, so don't think I want to dump cleaner in the gas tank yet. How should I proceed to try to clean the pistons up. I prefer a easy to get over- the- counter type fix. No piston soaks, no ordering from the internet, just keep it simple if possible.
Thanks.

 

[The_Eric]

Don't bother. Pistons won't be clean in operation. They'll always have a dark brown to black coating on them. If they are super clean, then you know there is something wrong.

 

[LeakySeals]

There is no OTC fix, only piston soaks using products ordered from the internet, sorry.

 

[CBR.worm]

The pistons and head surface will carbon up very quickly, it is actually not a bad thing. Engines tend to run better after a little carbon is built up.

You can get rid of some of the excess stuff, but you will not get your pistons 'clean' again with them in the engine.

 

[sittingduck57]

I agree wirh Eric,if you want clean pistons blow a head gasket. It'll steam clean them right up! Unless it's a heavy layer, no worries.

 

[ComfyShorts]

Originally Posted By: sittingduck57
I agree wirh Eric,if you want clean pistons blow a head gasket. It'll steam clean them right up! Unless it's a heavy layer, no worries.


Yep. I'd be worried if top of piston didn't have carbon on it.

 

[friendly_jacek]

LOL!

https://bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2550069#Post2550069

 

[mechtech2]

Originally Posted By: The_Eric
Don't bother. Pistons won't be clean in operation. They'll always have a dark brown to black coating on them. If they are super clean, then you know there is something wrong.


Right!

Some coating is normal. I would suspect a head gasket[coolant] leak if they were shiny clean.
But the plugs should be clean. A slight discoloration on the porcelain is right.