hummod 0 #1 Posted May 24, 2010 I wanted to mow with my 1992 520H and something broke. I was driving it about a bolck to get to the back side of the lawn when all of a sudden the rear wheels locked up. I can move it one wheel rotation each direction then it acts like the hydro pump hits an immovable object and starts whining loudly. The lift still works. I had to balance the rear end on a floor jack for the return trip to the garage. What happened? Larry Share this post Link to post Share on other sites
rickv1957 72 #2 Posted May 25, 2010 Possible broken end cap bolt?,Rick Share this post Link to post Share on other sites
hummod 0 #3 Posted May 27, 2010 I am starting to take the 520H apart to find out what happened. Most of the parts are off and I am ready to pull the hydro pump. I will need to pressure wash the transaxle first to try to keep dirt from getting inside. I need to get another 100 ft of garden hose to reach the tractor. The tractor cannot move and there is a 2 ft ditch where the road was now due to a paving progect. Rick, The wheels turn fine with the rear off the ground in opposite directions. The problem is there when both wheels turn in the same direction. I would think a loose/broken end cap bolt would prevent a complete rotation even in opposite directions. Thanks for the advice. I guess I will know more as I get further along. This is a good example of why we all need more than one Wheel Horse. Larry Share this post Link to post Share on other sites
hummod 0 #4 Posted June 7, 2010 Problem found. That Rick sure knows his Wheel Horses. As my only responce to my post he was right on the money too. The end cap bolts on the rear axle had come loose. One was already out, one was half out and binding the transmission, and the other two were only finger tight. Now comes the fun part of repair. I have a low hour 518-H rear that with a swap of the hydro pump and a few other parts should work. Numbers cast on the side of the transaxle match. Larry Share this post Link to post Share on other sites
Horse'n Around 22 #5 Posted June 7, 2010 The word OUCH comes to mind I dont know anything about that system but I hope that it isnt too much trouble to repair. John Share this post Link to post Share on other sites
Save Old Iron 1,566 #6 Posted June 7, 2010 You may want to double check to see if those bolts are Grade 8. Usually you don't see them bend that much before they snap. Nuts on the bolts are supposed to be hi strength also. :D Share this post Link to post Share on other sites
rickv1957 72 #7 Posted June 7, 2010 That same problem is common with the Ds,dont see it much with the smaller tractors, Rick Share this post Link to post Share on other sites
Raider12 13 #8 Posted June 7, 2010 I have seen these differentials on Ebay resently going for little to no money at all. $25? Might be worth looking into. Share this post Link to post Share on other sites
refracman 167 #9 Posted June 9, 2010 Haven't seen that happen to often since the D's. Before you start tearing apart the 518 make sure the pump drive gears are the same. They did change them. Might be easier to get new bolts from the dealer also. Share this post Link to post Share on other sites
hummod 0 #10 Posted June 9, 2010 I checked the pump output gear and the 1989 518-H and the 1992 520-H use the same 20 tooth gear. I did get a chance to put it back together tonight. It seems to work just fine now. All I had to buy was a 3 dollar pump gasket plus a new filter and some oil. I finally found a use for the 518-H tranxaxle that I have been moving around the garage for the last two years. Thanks to everyone for the replies and advice. Share this post Link to post Share on other sites
rickv1957 72 #11 Posted June 10, 2010 Glad to hear your up and running Rick Share this post Link to post Share on other sites