Rust around fuel tank neck

[1Lawman]

I have a 2012 model John Deere 5093E. There is significant light rust around the filler neck, chain that attaches to the screw on fuel cap and a small spring in the cap..Any idea what could account for this?

 

[M5farms]

I would assume it has a plastic tank. It is common to get rust around the filler neck on older metal tanks from water in fuel and just plain ole humidity . If it is plastic I would say it algae that's accumulating

 

[1Lawman]

Yes the tank is plastic..The rust is already somewhat pitted and the tractor is only a 2012 model..Is there any way to keep it from getting worse?

 

[M5farms]

plastic does not rust , It has to be something else

 

[1Lawman]

The tank is plastic. The filler neck, chain and spring are metal

 

[DLTTrekkers]

Condensation ! To prevent water in fuel fill your tank after each shift !

 

[DLTTrekkers]

Condensation

 

[1Lawman]

thnks

 

[BrokeFarmerJohn]

I concur, it's condensation from a partially full fuel tank, it happens a lot on older tractors, I pulled a fuel tank off my dad's 1950 Case SC that sat for 20 or so years, the top of the metal tank had 4-5 holes in it big enough that I could stick my finger in.

Only way to stop or slow it down is keep the tank full all the time but the neck would be more tricky.