Restoring a rusty engine

Ha ha further hijack

"big brother watching you"
I tend to try and NOT discuss Nitro and other explosives on some web sites knowing the NSA and others have key words they cull out messages to further explore....I often wonder how many airplane forum posts of 45% to 70% nitro they have to filter through....curious ...no

rsv1cox wrote:I think your on the right track with fine (0000) steel wool and a light cutting oil, but be careful.  You can remove all the finish on the cylinder with 50/50 vinegar or muratic (sp) acid the reblue with a quality (Brownells Oxpho) gun blue.  I did a thread on this sometime ago and when finished you cannot tell from new.  

Bob

Bob, when you are re-bluing, do you just do the exterior of the cylinder? If so, how do you block off the exhaust ports or the threads for the glow head to keep any of the compound from leaking into the interior?

I blue the whole cylinder, then use a 30 caliber brass bore brush to clean the blue off (hone) the interior used with a light oil. I think Cox International sells a similar brush.

It really does work rather well. The cylinders that I have done can't be told from new.

rsv1cox wrote:I blue the whole cylinder, then use a 30 caliber brass bore brush to clean the blue off (hone) the interior used with a light oil.  I think Cox International sells a similar brush.  

It really does work rather well.  The cylinders that I have done can't be told from new.  

Thanks, I plan to give it a try. I soaked the cylinder overnight in vinegar and was very surprised how well it cleaned the rust off. But it's bare metal now. Got all the metal parts in denatured alcohol now to soften any gunk. Then we'll see about re-bluing that cylinder and re-assembling!

Dan

Good luck. Make sure it's clean, clean, clean before you reblue. I use a small cup like a fruit cup and dip the cylinder in the solution for a minute or two. Move it around with a tooth pick to ensure uniformity within the fins. Dry, then dip again. If it's (the cylinder) cold ,I warm slightly with a hair drier. When your happy with the final look, neturalize the blue with a light oil.

Bob

Man, this is the most stubborn engine I have ever run across. I got it all cleaned up and tried a re-fit today. This driveplate is really something else. It sure didn't want to come off, and now it sure don't want to go back on. I twisted off 2 screw heads trying to screw it back down onto the crankshaft. Fortunately, they didn't break off too low to where I couldn't pull the broken part back out. Think I"m going to have to brute force it on, but what do I brace the backside of the crankshaft with while I'm hammering this bugger onto the front end?

Also, thinking starting is going to be a problem. As I turned the engine thru the compression stroke, I can see the pressure bubbling out around the piston at the top of the exhaust ports, thru the light oil I have the engine drenched in.

My handy dandy drive washer remover.



An adjustable wrench adjusts to the diameter of the case, heat with a heat gun, tap the shaft lightly with a tapping hammer and off it comes.

To put it back on I use a small deep socket size to the prop shaft and a solid surface to tap it back on. Done dozens this way.

Bob