Nickel plated compressor?

[Ike Carlson]

I'm getting my "new-to-me" compressor cleaned up and de-rusted. The previous owner left it outside all winter. It came apart, but the bottom end was pretty rusty. The crank cleaned up fine with a wire wheel and some polishing of the journals. The factory finish on the journals left a lot to be desired.

I have the crank case in the electrolysis tank now, and the cylinder block came out of the tank earlier today. I can still see the cross hatching on the cylinders! It's cleaning up real nice.

I'm scared it will rust again, being bare iron. I have seen a red paint applied to the inside of them, but I don't know what it is. I had the idea tonight to just nickel plate the inside and call it good. I could do it in about the same time as painting it.

Has anyone ever nickel plated a crank case? I have seen plated pistons and other internals, and I know they build up cranks with it to get tolerance back in the journals. I think it would be fine, but might as well ask.

 

[HMCFab9]

Idk about plating, but some guys use glyptal to paint the inside of engine blocks.
It may work for what you want to do also

 

[DocsMachine]

Nickel plate the inside of the crankcase?

As in, where all the oil splashes around while it's in operation??

That's the part you're worried about rusting?

Seriously, though, castings like that are typically painted with Glyptal, which is just a specialty kind of enamel paint, and primarily used to seal the surface of the cast iron where the oil goes. Both to keep the oil from soaking in to the cast iron too much, and also to encapsulate any leftover casting sand or other debris that might flake off and wind up in the oil.

In your case, there's no reason at all you can't just leave it bare iron, and forget about it. The oil splash will prevent the possibility of any rust.

Doc.

 

[matt_i]

I would be concerned about flakes. I don't think its quite like a pressure lube system and hopefully they'd settle to the bottom but the wrong piece of metal in the wrong place at the wrong time could lead to a bad day.

 

[astroracer]

Anything you do to it now, paint or plate, will never adhere to that old, oil soaked C.I. You will never get it clean enough to hold either. Waste of time and money. And, plating the inside of a crankcase? No, not necessary.
Mark

 

[Stuart in MN]

The inside should be fine as long as there's oil in there, and you don't leave it outside all winter.

 

[Ike Carlson]

My shop is not insulated yet, so it will not be in a climate controlled environment. That's why I'm asking. Temps here range from -50 to 120 F and the humidity is often 80-100% this time of year. I'm hoping the oil inside will keep it healthy, but I just wanted to be sure.

 

[astroracer]

I'm in MI. Same conditions you have. My compressor is on 24/7/365. It is in the shop but on the unheated side. I do not worry about rust inside the crankcase... What you do need to worry about is rust in the tank. Make sure you keep the tank drained if it runs a lot...
Mark

 

[Ike Carlson]

Astroracer- I will be using an after cooler and auto drain. It won't see a lot of use until next year.

 

[pcmeiners]

"The oil splash will prevent the possibility of any rust."

Mention this in other posts.. had a Curtis compressor under salt water for 17 days, absolutely no rust anywhere in the interior (bare cast). Worried about metal particles ? drop a magnet in the crankcase.
Nickel plating unneeded, also it is a good bit of work...metal needs to be absolutely oil free, then copper plating is needed before the nickel plate.

 

[Ike Carlson]

Was the salt water in the crankcase or was the compressor "just" under water?

 

[IdahoMan]

What you do need to worry about is rust in the tank. Make sure you keep the tank drained if it runs a lot...
Mark

What I was thinking. Plate the interior of the tank? Have a brass drain valve?

 

[pcmeiners]

Was the salt water in the crankcase or was the compressor "just" under water?

Yes, the entire compressor was submerged after Sandy, salt water and extremely fine sand were in the crankcase (I suppose the sand was from casting). On the 18th day I disassembled the entire compressor pump, including the valves, I did lose a brand new 5hp Baldor.

As to the tank... I have a QR 325 compressor also, at the drain I put a Tee , one side of the Tee ( 1/2"x 3/4"x 3/4" ) is for the drain (3/4"), one side I put a boat zinc for cathodic protection of the tank, like below in 3/4" thread, think mine is magnesium.

https://www.boatzincs.com/cummins.html

 

[Ike Carlson]

Nice!