This message is a reply to an archived post by BretSteed on September 08, 2020 at 12:55:42.
The original subject was John Deere 2640 with Reverser Hydraulic Chatter.
Just wanted to provide an update on this tractor and particular problem as this seems like a VERY common problem with reverser tractors... Although the hydraulic chatter stopped, fixing the check valve in top of the oil reservoir only remedied the problem for about 4 weeks. Since then, the 2640 chatter had gotten significantly worse. As I began to inspect the tractor I noticed that the hydraulic oil in the oil reservoir above the main pump was slowly leaking off back into the transmission housing. All of the usual suspects were checked such as the screen for debris, hydraulic filter and filler hole for mist... all checked out just fine. Then extensive pressure checks were performed and passed. Then the tractor was split and inspected for loose and cracked lines and new charge pump was installed. Once back together, the tractor performed 100% better but still chattered on startup. It took about 15-20 seconds for the main pump to get primed and the oil was still disappearing when the tractor was not running. As you can see in previous post/pictures in this thread, tractors equipped with reverser transmission did not have the bleed off valve installed in the return line back to the transmission. What we ended up doing was machining the original return line, pictured in this thread, so that the valve would fit perfectly. Once installed the tractor has performed flawlessly with no issues and the mysterious disappearing oil has stopped. I know that this particular problem plagues the john deere backhoes of this era... probably due to the use of the same reverser transmission... If you've got that problem, machining your line so that the bleed off valve fits might be an option to fix your problem! Hope that my story helps somebody else with annoying chatter! My 2640 was just too great of a tractor to abandon all hope and do what some suggest... blow it up with dynamite lol Tickled to death to have it finally fixed!
The original subject was John Deere 2640 with Reverser Hydraulic Chatter.
Just wanted to provide an update on this tractor and particular problem as this seems like a VERY common problem with reverser tractors... Although the hydraulic chatter stopped, fixing the check valve in top of the oil reservoir only remedied the problem for about 4 weeks. Since then, the 2640 chatter had gotten significantly worse. As I began to inspect the tractor I noticed that the hydraulic oil in the oil reservoir above the main pump was slowly leaking off back into the transmission housing. All of the usual suspects were checked such as the screen for debris, hydraulic filter and filler hole for mist... all checked out just fine. Then extensive pressure checks were performed and passed. Then the tractor was split and inspected for loose and cracked lines and new charge pump was installed. Once back together, the tractor performed 100% better but still chattered on startup. It took about 15-20 seconds for the main pump to get primed and the oil was still disappearing when the tractor was not running. As you can see in previous post/pictures in this thread, tractors equipped with reverser transmission did not have the bleed off valve installed in the return line back to the transmission. What we ended up doing was machining the original return line, pictured in this thread, so that the valve would fit perfectly. Once installed the tractor has performed flawlessly with no issues and the mysterious disappearing oil has stopped. I know that this particular problem plagues the john deere backhoes of this era... probably due to the use of the same reverser transmission... If you've got that problem, machining your line so that the bleed off valve fits might be an option to fix your problem! Hope that my story helps somebody else with annoying chatter! My 2640 was just too great of a tractor to abandon all hope and do what some suggest... blow it up with dynamite lol Tickled to death to have it finally fixed!
