What's Causing This Carb Jet Corrosion?

A friend of mine has a '53 CJ-3b with its original F134 that was his grandparents', which he got running again a year or so ago. At that time he rebuilt the carb and cleaned the internal parts, including the jets. He also replaced the gas tank, though he hasn''t replaced the fuel lines yet.

He's still working on getting it running well, and this weekend he took the carb jets out to check them. He sent me the photo below of what they look like now. Any thoughts as to what could be causing this corrosion?

 

My first thought would be "eff-em-all" gas.
Seen that green death many times.

 

Water in the fuel?

 

Yes lots, but none printable.

Ethanol. Which accumulates water, if vehicle is not driven often.

 

Yep. They don't like sitting. Clean them up, dump in some fuel treatment. Don't baby it get it out and run the crap out of it couple x a week.

 

X3 on E-Gas. I avoid using that stuff on anything that may sit a while between use, and never put that crap in the tank of my Jeeps unless there is no other alternative like being low on gas and it is the only thing available.

I am lucky to live next to one of the biggest lakes in the state. All of the gas stations around here have non-ethanol gasoline because of the many boats in the area.

 

X2 on finding non ethanol gas.

 

Here is a lawn mower carb I worked on last week. Another victim of ethanol.

 

X100
Just delt with some of the same issues on my carb

 

I've been just replacing carbs left and right on all my small engines and chainsaws. For 10 or 20 bucks from Ebay, it is easier and cheaper than trying to re-hab the old ones.

 

Are you using premium fuel ?

 

On the small engines, yes. Also adding Seafoam on a regular basis.

 

Wow. Haven't had any problems on my stuff......Knocks on a sequoia a tree........
But I run the carbs dry in the fall and use FRESH Premium in the spring......

 

Probably I should do that - but it is too many machines to keep up with. Four chainsaws, alone.

 

tru fuel for the win

 

Same here. Run them dry at end of season.

and use mostly tru fuel during the season.

lawn mower only gets non ethanol

 

Gotta say though I switched to a 40v ryobi weedeater. It does a great job

 

To the OP, X10 that is alcohol in your fuel.
For you small engine guys, either run it out of fuel every time you use it or don't use alcohol mixed fuel. I buy obscenely expensive aircraft fuel because it's alcohol free, low lead and 100 octane.
I too had years of chainsaw engine issues that were finally diagnosed as alcohol related. I tried stopping drinking bourbon but turns out it wasn't that kind of alcohol.

 

We mostly drink corn whiskey down here in the South, that brown stuff will get you in trouble. Even so, I only use non-ethanol 100% gasoline in all of my small engine equipment, and Jeeps. If it is going to sit a while I run the carb dry.