using lye on scored cylinder?

[chuckwood]

I'm planning on restoring a seized up husky 350 that was given to me. Most of the scoring is on the exhaust side of the cylinder, and I'm going to see if I can fix the cylinder first before buying a new one. I'm reading about using muriatic acid solution to eat the aluminum stuff off the cylinder walls. However, this particular acid will also disolve all sorts of other metals, maybe including the cylinder coating. Has anyone tried using sodium or potassium hydroxide, the stuff that is sold for drain cleaner? It's cheap, doesn't fume and burn your nose like muriatic acid, and there are only a few metals it will attack, and one is aluminum. Why wouldn't hydroxides, or generically called "lye" work better for cleaning aluminum off a cylinder?

 

[logging22]

:dunno:

 

[ironman_gq]

It attacks aluminum very badly and almost rots it. Our auto shop uses hydroxide based degreaser in its hot tank and a set of pistons got in there one time. When he pulled em out in the morning they looked like burnt marshmallows they'd turned an ugly white color and had foamed over. The acid is a lot gentler on the cylinder i would think

 

[mtngun]

It's cheap, doesn't fume and burn your nose like muriatic acid, and there are only a few metals it will attack, and one is aluminum.

I haven't tried it on a 2-stroke cylinder, but lye does attach aluminum, so in theory it should work, thought I don't know how quickly.

Lye is not pleasant to work with. Wear rubber gloves and safety glasses or goggles. Have water nearby for rinsing in case the lye splashes on you or on the aluminum part of the cylinder.

 

[HimWill]

You can use either one,acid or a caustic soda,to remove the aluminum.The acid is commonly used because it's recommended most often.The use of lye in various forms,such as drain cleaners and oven cleaners,works just as well and is a little easier in my opinion to use.The reason I like them better is that they are thicker and stay where you put them,they work slower and you have better control when using them.

Before you use either method,be sure your cylinder is plated.The nikasil and chrome plated cylinders will be OK,an unplated cylinder would be ruined.

 

[peterc38]

You can use either one,acid or a caustic soda,to remove the aluminum.The acid is commonly used because it's recommended most often.The use of lye in various forms,such as drain cleaners and oven cleaners,works just as well and is a little easier in my opinion to use.The reason I like them better is that they are thicker and stay where you put them,they work slower and you have better control when using them.

Before you use either method,be sure your cylinder is plated.The nikasil and chrome plated cylinders will be OK,an unplated cylinder would be ruined.

As you state both of these chemistries lye (sodium hydroxide) and acid (Hydrochrloric) will attack/remove aluminum. Sodium hydroxide is used to etch aluminum to prepare it for anodizing.

However, one caveat is if the cylinder is chrome and you use hydrochloric/muriatic acid, it will also attack the chrome. Hydrochloric acid is often used to strip chrome plating.