Knivens894
Well-Known Member
The insulation on the wiring in my JD 490E has gone south as confirmed with a wire megger. The wiring is bundled and generally lays on the bottom of the operator's deck. It takes signals from the various sensors and through the computer, it tells the hydraulic controls of the main pump what to do. Over the years many hoses have been failed, and the hydraulic fluid has drenched most all of the wiring. I researched the problem a bit on the net and found out ALL petroleum products leach the plasticizing additives out of the PVC insulation on the wire. Exposure to any petroleum product, over time, and particularly with elevated temperature, causes the wire's insulation to crack, thus causing faults which might come and go with the vibrations of the operation. When it becomes advanced, as in my machine, it starts killing sensors and solenoids, resulting in jerky, stalling, and overheating behaviors.
I tried to find a new wiring harness for the machine, but it is no longer available. During my research I found that wiring insulation standards have changed over the years after it was recognized exposure to petroleum was having this effect. The current highest standard petroleum resistant wire is AWM 21098. This wire is coated with a clear sleeve which isolates the insulation from the petroleum products. The sleeve extends the life of the wire's insulation, but is not a cure all for the problem.
My question is, "Has anyone else experienced this problem, and if so, how was it solved?" Matching all the wire colors when re-wiring would probably be impossible. I am considering using multi-paired, individually insulated conductor wire covered with an outside insulation sheath. Any and all experience and solutions shared will be sincerely appreciated.
I tried to find a new wiring harness for the machine, but it is no longer available. During my research I found that wiring insulation standards have changed over the years after it was recognized exposure to petroleum was having this effect. The current highest standard petroleum resistant wire is AWM 21098. This wire is coated with a clear sleeve which isolates the insulation from the petroleum products. The sleeve extends the life of the wire's insulation, but is not a cure all for the problem.
My question is, "Has anyone else experienced this problem, and if so, how was it solved?" Matching all the wire colors when re-wiring would probably be impossible. I am considering using multi-paired, individually insulated conductor wire covered with an outside insulation sheath. Any and all experience and solutions shared will be sincerely appreciated.