My serial# and local Kubota dealer will tell you when my Kubota was built.
Sounds more like a fuel line.
Your closest JD dealership would be able to get closer to the year than most, however if this is correct, the 4520 was only made in 1969 and 70:
TractorData.com John Deere 452 tractor information
I don稚 know. I was on the road driving it back to my house and I could smell something burning. I got out and a small hose had some fire. In a matter of 30 seconds it was completely on fire. I think it may have been a hydronic hose.
I'd had my tractor for less than a year and one day I'm setting up to use the post hole digger and my son says "I'm smelling a lot of diesel." me: "yeah well it's a diesel" son: "no, look, there's something just pouring onto the ground"
Rodents (of the usual size) had chewed through the diesel return line.
Needless to say, it's kept in a container now...
I'd had my tractor for less than a year and one day I'm setting up to use the post hole digger and my son says "I'm smelling a lot of diesel." me: "yeah well it's a diesel" son: "no, look, there's something just pouring onto the ground"
Rodents (of the usual size) had chewed through the diesel return line.
Needless to say, it's kept in a container now...