Hello all: A new fuel pump was installed in my 580B backhoe and it has new found power. Today, I had the A38033 Flow Control SPOOL blow out of the shuttle valve assembly! The spool was bent slightly and landed by the seat. I had TCH oil pumping out of the shuttle valve! A few moments earlier the spool had extended too much out of the valve assembly and I stomped on the dump pedal to try to get it back in. I don't think I applied enough pressure to bend the spool, but who knows. So the question is why did the spool blow out? I can replace the spool valve and reassemble, but will it happen again? Thanks for any advise Joe Ramirez
Joe, Can't seem to find CNH, I'm borrowing a friends computer . Obviously A38033 is the valve attached to your 'clutch' pedal. Yes they will fly out with lots of oil loss without the linkage attached(or broken). Don't ask how I know. The linkage that most 580B's end up with is a long 1/4" bolt going through the roller bearing that rides in the cam slot. I cannot remember exactly as it's been at least a year since I worked on one. Whatever fastener you use it Must be mounted rigid, to the hole in the end of the 'dump' valve, as I call it. There is a measurement of 3.1" taken off a bracket that limits spool travel. I don't have my manual right here handy or my pictures but will post them tomorrow night if needed. The clutch pedal must immediately return all the way to the stop, with your foot off it. The cam bolt must hold the cam so that it rotates smoothly and not wobble, and the bolt has an eccentric on it for adjustment. The spool probably blew out because there was nothing to hold it in. I don't know about the condition of the 'dump' valve bore, sounds like the spool is toast. Would be good to put a new seal in if possible, perhaps get the whole valve assembly used from a wreck, if needed. Keep in mind that there are 2 different gaskets used under the valve body, dependent on machine serial #( located on the steering column), also different valve bodies, and possibly 2 different spools. If you remove your old valve body for any reason, make a note of where the spring and ball go. Be very careful reinstalling the valve body and gasket, with the ball and spring sandwiched in between. Phil
Spool valve linkage Phil: Thanks for the help! I guess when you write "The linkage that most 580B's end up with is a long 1/4" bolt going through the roller bearing that rides in the cam slot." is the replacement solution you created to solve this problem of worn, loose Case parts. I will order a new spool valve and seal, and then install it without taking the valve assembly off the torque tube. Any problems with this idea? I ask so if I need a valve assembly gasket, I can order it beforehand (and Case can order it from their warehouse): I live 2 hours from the Case dealer. The backhoe is at a friends' house behind locked gates right now, so I can't go look before I ask this question. Is the bore of the roller bearing that rides in the cam slot, a 1/4" hole, or do I need to find a new correctly sized, aftermarket roller bearing? Thanks Phil: you are a godsend to me and I suspect many of us. The advice and relief you provide is very much appreciated!:notworthy Sincerely, Joe Ramirez Spring Branch, Texas
I'm glad I can help. It's the learning, the wealth of info here I like, and there's lots I don't know. Chaps like ATCO, gggraham, Bill, and lots of others enjoy helping others and we all can learn from them at the same time. I would be tempted to try another spool first. Might be a burr or other mark in the bore that needs a little touch up but try a spool first, new or used, and see how it slides in. Yes the original sealed bearing has a 1/4" hole in it. I still can't remember how the 1/4" bolt goes, but I think it has to have lots of thread and 2 nuts on it, one locks the bolt tight in the hole of the spool, the other nut holds the roller bearing near the end of the bolt. The very end of the bolt goes in the bracket slot, not sure. Sometimes the cam gets wobbly on it's pivot bolt from wear. The measurement indicated in the next post is with the foot off the clutch pedal. A very long 1/2" extension on a 3/4" socket with a universal, will allow loosening and tightening the cam follower retaining bolt nut, from the right side of the machine. Phil
Check post #183 for a picture. Phil