Bad carbon on pistons - how to clean?

[Michael_P]

Anyone who has done a head gasket can tell you how sparkly clean the piston is that was subjected to the (coolant) leak. Steam works. Ive taken medical capnography tubes inline with a ported vacuum source. Then the small tube into a bottle of water kept in the passenger compartment. It draws the water in via a venturi effect, so the faster the engine goes, the more water it draws. At idle it virtually draws no water. I have borescoped pistons after running a few quarts of water through and it works. Below is a picture of a capnography tube If the head is off, I would buy one of those handheld steam cleaners.

 

[abycat]

You could purchase a water /meth injection system for your car and reap both the benefits from it. Cleaning power of steam and the timing advance benefit as well. The turbo guys that use it have very clean engines.

 

[Testoprop]

It really works and does a great job just be careful to not get it on anything

 

[tony1679]

Originally Posted By: GatorJ

Originally Posted By: tony1679

Originally Posted By: shDK

Spraying clubsoda in the intake at about 1200-1500 rpm works great. The carbon dioxide works really effective.

Not trying to criticize, but since I've never heard of this, can you provide some sort of evidence to back this up?

Club soda is carbonated water.

I know what club soda is. I meant provide evidence that the C02 is doing anything beneficial.

 

[nicholas]

zmax - seriously>

 

[SteveSRT8]

Originally Posted By: 440Magnum

Originally Posted By: Trav

Edit: just because its black doesn't necessarily mean it need cleaning, a carbon layer on the pistons protects the piston heads. It only becomes an real issue when its excessive and you get carbon knock or other symptoms of excessive carbon.

So glad to see this posted... its absolutely true. Its perfectly normal for piston crowns to look dark, even pitch black, and slightly rough. Ideally there should not be any carbon built up thickly, but a thin film almost always happens. Its when you start getting globs of carbon as thick as a fingernail or more that you need to worry. Until that point, any "cleaning" you do is potentially more harmful than good (washing oil off cylinder walls, washing dislodged grit down into the ring spaces, etc.).

This. In any engine you must first learn not to disturb the equilibrium that has been reached after many miles. As stated, some carbon as a film is actually normal and does not hurt anything. Putting any liquid into a modern "dry" manifold is a risky proposition as they are not designed to suspend liquids with the air. If it puddles or pools the results can be catastrophic....

 

[68redlines73]

Originally Posted By: tony1679

My two cents, use a cleaner that has PEA (I believe the Valvoline you are using does. My favorite is Techron. Not sure if that is available in Australia though). I don't think using a higher RON (or R+M/2 Octane here in the U.S.) is going to do anything for you unless you are truly knocking. I'm no expert though.

http://www.caltex.com.au/FPL%20PDS/Techron%205000.pdf

 

[tony1679]

Originally Posted By: 68redlines73

Originally Posted By: tony1679

My two cents, use a cleaner that has PEA (I believe the Valvoline you are using does. My favorite is Techron. Not sure if that is available in Australia though). I don't think using a higher RON (or R+M/2 Octane here in the U.S.) is going to do anything for you unless you are truly knocking. I'm no expert though.

http://www.caltex.com.au/FPL%20PDS/Techron%205000.pdf

I guess it is. Thanks for posting the link!