Marco1958
New member
A few weeks ago I replaced two hydraulic hoses on my TaskMaster 438D tractor. One hose was from the pump to what the I thought was the pressure port on the joystick control valve. The other hose was from the joystick to the oil sump. The joystick has six ports. I started the tractor up and within a few seconds the hydraulic pump cracked and began spewing oil.
I ordered a new replacement hydraulic pump and AGAIN the new pump blew. I am at a loss as to how to proceed. This is where I am confused... I installed the new pump and reassembled the hoses being quite confident that they were routed to the proper ports from the pump to the joystick with the pressure line being closest to the relief valve on the joystick (left arrow - photo attached). I started the tractor up and lifted the bucket (FEL) about a foot off the ground and raised the 3 point hitch with attached box scraper. I was able to move the tractor from the field to the barn (about 1,000 feet). In the barn with the tractor still running using the joystick I lifted the loader about 2 feet off the ground, then heard a loud crack when the pump began spewing oil. I am not sure, but I am thinking that there has to be a blockage somewhere causing the pump to "deadhead". But even more confused because I was able to move the tractor with the hydraulic pump running and the engine revved up without hearing any strain on the motor until the point of trying to lift the bucket in the barn. It doesn't make any sense to me because if there was "deadheading" I don't believe I would be able to drive the tractor for the 5 minutes that it took me to get it in the barn. It wasn't until I used the joystick to raise the loader that the problem occurred. Any ideas on how I might troubleshoot this would be greatly appreciated? Could there be a blockage in the joystick control valve?

I ordered a new replacement hydraulic pump and AGAIN the new pump blew. I am at a loss as to how to proceed. This is where I am confused... I installed the new pump and reassembled the hoses being quite confident that they were routed to the proper ports from the pump to the joystick with the pressure line being closest to the relief valve on the joystick (left arrow - photo attached). I started the tractor up and lifted the bucket (FEL) about a foot off the ground and raised the 3 point hitch with attached box scraper. I was able to move the tractor from the field to the barn (about 1,000 feet). In the barn with the tractor still running using the joystick I lifted the loader about 2 feet off the ground, then heard a loud crack when the pump began spewing oil. I am not sure, but I am thinking that there has to be a blockage somewhere causing the pump to "deadhead". But even more confused because I was able to move the tractor with the hydraulic pump running and the engine revved up without hearing any strain on the motor until the point of trying to lift the bucket in the barn. It doesn't make any sense to me because if there was "deadheading" I don't believe I would be able to drive the tractor for the 5 minutes that it took me to get it in the barn. It wasn't until I used the joystick to raise the loader that the problem occurred. Any ideas on how I might troubleshoot this would be greatly appreciated? Could there be a blockage in the joystick control valve?
