I'm having a problem leaking fuel when the tractor sits for several weeks. This problem started last winter. During the winter the tractor was used several times a week for feeding and it appeared a leak was occurring around the fuel cap. I replaced the fuel cap. After we stopped using it to feed it is getting used only about once a month. It is parked in an open shed with dirt/gravel floor. Most recently when I go to use it I see the ground is wet with fuel under the tractor, but it's not obvious by any wet parts on the tractor where the leak is occurring. Tractor is also harder to start. I've found the primary fuel filter contains very little fuel when this happens. If I take it off and fill it with fuel, tractor starts normally.
Is it possible for the sun to heat the tank up enough to pressurize the system creating the leak, then as it cools siphon the fuel out of the filter?
I see later models have a check valve between primary filter and tank. Mine doesn't.
Why doesn't the tank vent pressure thru a new cap?
Gave up and requested a service call from a local mechanic with years of John Deere experience. He foudn the O ring missing between the primary filter and the clear sediment bowl.
I must have lost it when I last changed the filter