thirdgenbird

i currently have my head off and i want to be 100% sure ive got everything clean before it goes back together. my leak down numbers were perfect and i want to keep it that way. thanks!

m73m95

If it ain't broke, don't fix it..... If you have perfect leak down numbers, don't mess with it. The carbon is actually helping to seal the rings.

Make sure no carbon broke off either the top of the cylinder walls or the top of the pistons. Maybe vacuum out the bores to make sure. Carbon is hard, and will scratch a cylinder wall of a piece gets trapped between the piston and bore.... but other than that, bolt it back together and run it.

thirdgenbird

this is my biggest fear at this point.

m73m95

While the head is off, you can turn the engine by hand. Just slowly turn it through a few revolutions and look for any loose particles.

The combustion chamber is a pretty violent place. If you haven't knocked anything loose doing the head gasket cleaning, then everything should be still in place.

Luis de Prat

Although a different car, I just cleaned the piston tops on the 4 cylinder engine in my SAAB 900 and the easiest way to get the carbon off is using gasoline, brake cleaner, and WD-40. Spray them down with WD-40 to protect the surface when you're finished. Good luck with it!

thirdgenbird

thanks guys

Perry 951

I toss a little Lucas Oil Stabilizer between the bore and piston to lube the rings and trap any debris before rotating the bottom end. The Lucas is sticky enough that it will pick up little bits of junk and leave it at the top of the bore to be wiped away.

thirdgenbird

you guys are a life saver.

i think this "project" is going to be worth the time/expense. i am excited to see my clean and improved engine bay (but i promise to take my time)