karman1970
New User
Hi all. Just bought my first tractor a few weeks ago. Ford 640, not sure of the year but I think it's a fairly early model.
It came with a Bush Hog when I bought it. Used it few times in the evenings after work to cut my pasture. No issues. First Saturday rolls around so I had all day to use it. Only thing I noticed when I first pulled it out of the barn to check fluids was that the I had the Bush Hog up in the air with everything shut off and it just dropped a couple inches out of nowhere. Kind of startled me, but I didn't think much of it. A couple hours later, I look behind me and the Bush Hog has all of a sudden dropped, so the front edges are digging into the ground. I stopped and tried to get it to pick up, but it won't do anything. Finally gave up and went inside to do some research. I went back out 30 minutes or so later and got it to pick up, but it only made it half way back to the barn before it dropped again. Had to wait a while again. Got to the barn and did some poking around. Check the pump, still seems to have prime. I noticed the arms were bouncing or "hiccupping". Looked through the fill hole and didn't see any leaks. Figured time to tear into the lift. First things I noticed when I got it apart were A) very grungy and looked like corrosion and rust, must have gotten moisture in it at some point B) measured the linkage and found it out of adjustment and it runs out of adjustment to get everything in spec. Decided to do a complete tear-down, which leads me to some questions on what I do and don't need to replace.
Here is the cam on the lift arm. I don't have a new one to reference, but it looks worn and flat-spotted in the middle. It also looks like someone may have tried to weld or braze a new surface on it. The dowel that rides on the cam also looks like someone put a little brazing on it. I haven't been able to get the lift arm off yet, but I think with my press and a torch I might be able if need be. I don't think I'll be using draft control all that much, so does it really matter if the cam isn't perfect, or will it prevent me from getting the linkage adjusted?
Next is the plate the draft rod rests against. I've heard it's impossible to get the linkage adjusted right if this is worn, as well. Think this needs to be replaced? If so, is it necessary to get one with the pin?
Finally, the cylinder and piston themselves. I didn't see any leaks when it was trying to diagnose the bounce. Got the piston out today and there looks like maybe some corrosion from moisture on couple spots of the piston. There are matching spots on the cylinder, which makes me think it maybe sat for a long time at some point. Also, there is some scoring on the cylinder and the piston. The ones on the piston are very light - I can only catch my finger nail on one. Any advice here? Will it be okay like this or do I need to try and clean up and polish the surfaces or do I need to get some replacements? Piston isn't a big deal, but it would be nice to avoid having to buy a new cylinder if I can avoid it.
Thanks in advance for any assistance!
It came with a Bush Hog when I bought it. Used it few times in the evenings after work to cut my pasture. No issues. First Saturday rolls around so I had all day to use it. Only thing I noticed when I first pulled it out of the barn to check fluids was that the I had the Bush Hog up in the air with everything shut off and it just dropped a couple inches out of nowhere. Kind of startled me, but I didn't think much of it. A couple hours later, I look behind me and the Bush Hog has all of a sudden dropped, so the front edges are digging into the ground. I stopped and tried to get it to pick up, but it won't do anything. Finally gave up and went inside to do some research. I went back out 30 minutes or so later and got it to pick up, but it only made it half way back to the barn before it dropped again. Had to wait a while again. Got to the barn and did some poking around. Check the pump, still seems to have prime. I noticed the arms were bouncing or "hiccupping". Looked through the fill hole and didn't see any leaks. Figured time to tear into the lift. First things I noticed when I got it apart were A) very grungy and looked like corrosion and rust, must have gotten moisture in it at some point B) measured the linkage and found it out of adjustment and it runs out of adjustment to get everything in spec. Decided to do a complete tear-down, which leads me to some questions on what I do and don't need to replace.
Here is the cam on the lift arm. I don't have a new one to reference, but it looks worn and flat-spotted in the middle. It also looks like someone may have tried to weld or braze a new surface on it. The dowel that rides on the cam also looks like someone put a little brazing on it. I haven't been able to get the lift arm off yet, but I think with my press and a torch I might be able if need be. I don't think I'll be using draft control all that much, so does it really matter if the cam isn't perfect, or will it prevent me from getting the linkage adjusted?
Next is the plate the draft rod rests against. I've heard it's impossible to get the linkage adjusted right if this is worn, as well. Think this needs to be replaced? If so, is it necessary to get one with the pin?
Finally, the cylinder and piston themselves. I didn't see any leaks when it was trying to diagnose the bounce. Got the piston out today and there looks like maybe some corrosion from moisture on couple spots of the piston. There are matching spots on the cylinder, which makes me think it maybe sat for a long time at some point. Also, there is some scoring on the cylinder and the piston. The ones on the piston are very light - I can only catch my finger nail on one. Any advice here? Will it be okay like this or do I need to try and clean up and polish the surfaces or do I need to get some replacements? Piston isn't a big deal, but it would be nice to avoid having to buy a new cylinder if I can avoid it.
Thanks in advance for any assistance!