I'm new here trying to get some advice on repairing my tractor.
The tractor is a 1973 John Deere 301 with a front loader and a rear 3-point hitch. After working the tractor for several hours my hydraulic system stopped working (both the loader and 3-point hitch would not work) but the tractor would continue to drive forward and back with the power steering working sporadically. Initially, I thought an internal relief valve opened up and pressure was getting bled off internally, particularly since there was no external leaks or strange noises coming from the tractor or pump. I stopped the tractor, turned it off, and let it sit for about 15 minutes. I then started it and moved it forward, and in the process of doing so, the hydraulics came back to life again like there was no problem. Well the next weekend the hydraulics started to act up again and this time started to simply loose pressure (i.e. loader would slowly raise until it wouldn't raise at all). Again, both the loader and the 3-point hitch were affected, but the tractor could still be moved.
In attempting to diagnose the problem, I first disconnected the coupler on the hydraulic pump to disconnect it from the crank off the front of the motor and move the pump by hand. To my surprise, I was able to move the pump input shaft by hand (I thought it would be much more difficult, but dismissed it since it wasn't under pressure). Next I dropped the filter bowl to replace the filter element under the tractor, and ......crap......the oil on the outside of the filter was contaminated with what appears to be brass and metal shavings. I replaced the filter anyway, fired up the tractor and drove it around for about 10 minutes. Upon the initial startup I had hydraulic pressure, or at least enough to raise the loader and the 3-point hitch with about 1500 pounds hanging off of it. However, after about 5 minutes of operation, the loader started to act sluggish until is wouldn't raise at all. Same with the 3-point hitch.
Because I found metallic material in the oil, I'm thinking the hydraulic pump died. But if the pump was dead, how could it build enough pressure to raise the loader? Also, where would the metallic material be coming from? I suspect the pump, but could it also be coming from the wet clutch on the reverser?
Any advice on diagnosing my problem and repairing it would be much appreciated.
Thanks in advance, Don.
The tractor is a 1973 John Deere 301 with a front loader and a rear 3-point hitch. After working the tractor for several hours my hydraulic system stopped working (both the loader and 3-point hitch would not work) but the tractor would continue to drive forward and back with the power steering working sporadically. Initially, I thought an internal relief valve opened up and pressure was getting bled off internally, particularly since there was no external leaks or strange noises coming from the tractor or pump. I stopped the tractor, turned it off, and let it sit for about 15 minutes. I then started it and moved it forward, and in the process of doing so, the hydraulics came back to life again like there was no problem. Well the next weekend the hydraulics started to act up again and this time started to simply loose pressure (i.e. loader would slowly raise until it wouldn't raise at all). Again, both the loader and the 3-point hitch were affected, but the tractor could still be moved.
In attempting to diagnose the problem, I first disconnected the coupler on the hydraulic pump to disconnect it from the crank off the front of the motor and move the pump by hand. To my surprise, I was able to move the pump input shaft by hand (I thought it would be much more difficult, but dismissed it since it wasn't under pressure). Next I dropped the filter bowl to replace the filter element under the tractor, and ......crap......the oil on the outside of the filter was contaminated with what appears to be brass and metal shavings. I replaced the filter anyway, fired up the tractor and drove it around for about 10 minutes. Upon the initial startup I had hydraulic pressure, or at least enough to raise the loader and the 3-point hitch with about 1500 pounds hanging off of it. However, after about 5 minutes of operation, the loader started to act sluggish until is wouldn't raise at all. Same with the 3-point hitch.
Because I found metallic material in the oil, I'm thinking the hydraulic pump died. But if the pump was dead, how could it build enough pressure to raise the loader? Also, where would the metallic material be coming from? I suspect the pump, but could it also be coming from the wet clutch on the reverser?
Any advice on diagnosing my problem and repairing it would be much appreciated.
Thanks in advance, Don.
