Engine Coating and Block Protection?

[battlecry]

http://corrosion-doctors.org/Aircraft/Aloha.htm

Grew up in the tropics.  Hatred for corrosion is encoded in my genes.  Protect all metals, all the time.  Rust never sleeps.

If you like aluminum, you treat it with a weak phosphoric acid solution and then chromic acid.  No need to tank it, you can just brush it on.  Use scotchbrite to clean the white oxide before the phosphoric acid.  After that you can prime and paint if you want.

Iron rust molecules are physically larger than non corroded molecules, that is why iron and steel flake off so dramatically.  Aluminum oxide doesn't have as big a dimensional problem, but it weakens the structure and flakes off too.  The initial layer of corrosion in aluminum does form a coating that slows down the oxidation to some extent, but it does not stop, and it becomes really bad when exposed to road salts or stressed.  You end up getting pinholes and stress cracks.  The structural alloys in our parts, whatever they are, are more corrosion prone that pure aluminum.

If you are studying engineering, think of everything wanting to go to the lowest energy and highest disorder state.  The lowest energy state of metals is a pile of rust.  It takes energy to convert and maintain that pile of rust into the ordered shape of the engine cases.  You must spend energy to prevent corrosion from raising the entropy of the cases until they become a pile of stable dust.  (sorry for the trip down memory lane)

[He Man]

Im not going to keep going with this. I agree with both of you guys. It just seems like we are talking about 2  different things here.

Aluminum Oxide, formed by O2 exposure. Will make the protective coating and it will not continue to rust. If you start talking about other oxidation states fromed by other elements, some of them will penetrate teh oxidation layer and continue. But O2 wont. Thats my point. But in practice. It depends on where you live that will determine the ultimate outcome Northeast, rust belt, sun belt. etc.

And to ducpainter, no im not an ME and plane wings stretch, bend, expand, compress, all that stuff will knock off the oxidation layers + moisture inside the wing from humidity and temp differences.

And im painting my engine cause of the conditions i ride in. The Aluminum on my engine block will oxidize, then itll get blown off by a rock, salt water spray, make the beast with two backsing acid rain, tar, random chemicals that factories throw into the streets.

and most importantly, itll get on my white shirt cause im a squid in the summer. 

btw: your all right anyway. Practice over concept. Oxidation is bad and should be avoided at all cost unless your looking to harvest the oxdation.

[Popeye the Sailor]

This conversation hurts me so.





Just paint the dang thing.

[♣ McKraut ♣]

Does anyone know what coats the engine block?  My engine block's surface is chipped underneath the front end.  It is a little tough to see from the below picture but the coating is definitely chipped to the base material. 

Will the block begin to rust and is there something I can apply to protect it?

so, to the op's question...is there something he can apply, besides actually going through the process of engine removal and total repainting of the block?  mine is doing the same thing on the alternator cover side...towards the front.  everywhere else it's fine, though...so this isn't something i want to have to remove the cover for (for the time being at least... and definitely not during riding season).  is there something you can apply in the interim until you get to the colder months, that doesn't look completely ghetto?  maybe it's just not even that big of a deal to worry about...but i just hate seeing it flaking like that.  i have this urge to pick of the flaking bits or sand it down and coat it with something protective, for now at least.

[ducpainter]

so, to the op's question...is there something he can apply, besides actually going through the process of engine removal and total repainting of the block?  mine is doing the same thing on the alternator cover side...towards the front.  everywhere else it's fine, though...so this isn't something i want to have to remove the cover for (for the time being at least... and definitely not during riding season).  is there something you can apply in the interim until you get to the colder months, that doesn't look completely ghetto?  maybe it's just not even that big of a deal to worry about...but i just hate seeing it flaking like that.  i have this urge to pick of the flaking bits or sand it down and coat it with something protective, for now at least.

It can be treated with Alodine, but the location of the damage will require a durable coating, paint, to make it last.