BigR 3 #1 Posted December 30, 2015 Yesterday morning I finally was able to use my newly purchased 1992 520H to snow blow the 8" of snow from the driveway. Everything worked well and I was very impressed with the power upgrade from my former 416-8. Plus I really enjoyed the hydro lift So last night after work I just needed to clean up the end of the driveway where the plow wind rowed the snow. However, when I went to start the tractor back up all it would do is "click". I sounded like it was behind the gauges, so probably a relay. With the key on all of the gauges seemed to work, and the lights worked too. I popped the hood and started tracking voltage with a multi meter. I checked the fuses and found the 25amp had 12.5 v on one side and only 10v on the other. I had to use a pliers to pull it and found it was slightly melted, but not blown. I took a quick look at my not running 416 and saw that it had a 25, 30, and 15amp fuses. So I figured the 25amp I pulled out was actually suppose to be a 15. So I found a 15amp and plugged it in, and the tractor fired right up. Problem solved...so I thought. I pulled it outside to let it warm up before putting it to work. While sitting there I brought the throttle up some and saw the voltage gauge increase with the RPM's. The tach also was reading the increase. Suddenly the engine started sounding like it was working under a slight load and the voltage dropped to 10-11 and the tach went to 500 and wouldn't move from there. Everything else seemed to be fine, so I cleaned up the snow I needed moved. While I worked the head lights did seem to get dimmer, but the LED's I have mounted to the cab roof seemed okay. I did notice this in the morning workout but figured it was just the brighter LED's making the head lights look dimmer. After the work was done I pulled it back into the garage. I did not try and restart the tractor again or look at the fuses. I figured I save that for this weekend. I wondering if anyone has any ideas on were to start looking for a possible issue? Also, what is the correct order for the fuses in the fuse block? Mine are 25/30/15 from the back to the front of the machine. I'm wondering if the previous owner threw in a 25 amp instead a 15amp, there may be others out of place. Sorry for the long worded story and thanks for any help! Share this post Link to post Share on other sites
rokon 64 #2 Posted December 30, 2015 The fuse block and the 9 pin connector are known high resistance trouble spots on the 4 and 500 series onan powered horses. Check this post for a nicely done repair.http://www.wheelhorseforum.com/topic/59276-520-h-with-multiple-electrical-and-ignition-issue/?do=findComment&comment=546782 2 Share this post Link to post Share on other sites
BigR 3 #3 Posted December 30, 2015 Rokon, thanks for the link to that post. Yikes!!! I was hoping it wasn't going to be that involved. Is there anything I can test to verify the fuse block and/or 9 pin connector is the problem before cutting wires? When I pulled out the melted 25amp fuse I checked the fuse terminals and everything looked good. The fuse block didn't look melted at all. Also the other 2 fuses looked fine. Do you have any idea on the order the fuses are suppose to be in the block? Share this post Link to post Share on other sites
rokon 64 #4 Posted December 30, 2015 why redsquare is awesome=http://www.wheelhorseforum.com/topic/58405-520-h-wont-start-hour-meteroil-sensor/?page=2#comment-539898 checking the circuits with an ohmmeter would be one way, checking voltage drop with a voltmeter across the circuit is more accurate way to diagnose them, just because there is continuity does not mean the circuit can handle the electrical load it is meant to carry. That being said, these are known issues and lets say the troubleshooting or diagnosis has been done for you by many of the members here already. If you don't feel comfy doing the repairs, maybe there is another redsquare member near you willing to help or if you know any decent mechanics, it is basic electrical repair.I would stay away from crimp type connectors, soldering and heatshrink is the way to go here for a permanent repair. 3 Share this post Link to post Share on other sites
boovuc 1,090 #5 Posted December 31, 2015 Hi BigR, Rokon is correct. Just do a search on here of all of us who have the first generation 500 series tractors and you'll see a lot of issues squarely holding that fuse block and thin wiring responsible for electrical snafus. To get you through the winter with your 520, disconnect your battery and with a thin file, touch up the connectors at the bottom of the fuse block. They are most likely pitted/tarnished and are not making good connections with the fuse ends. This is causing your heat on the fuse. (Not to mention the wires going through the block). Get a can or two of electrical contact cleaner and spray the fuse block connectors. You may also want to pull the other connectors throughout the tractor circuits and spray/file them a little. Be very careful taking the terminal ends apart. Heat and time makes the plastic brittle as all get out and they "could" crumble on you. (Opening up another can of worms). These things need done to every 500 series first generation when you get them as sooner or later, they will cause problems and they should be replaced to make them dependable each and every time you get on them. 1 Share this post Link to post Share on other sites
cleat 4,936 #6 Posted December 31, 2015 The first generation maroon 520's had the charge wire go right from the regulator down to the starter solenoid with a fuse close to the solenoid. That takes this load off of the 9 pin connector. I have all of mine wired this way including the 416 using a sealed fuse holder. May not solve all of the 520's electrical issues, but it does help. This picture shows the sealed fuse holder tied to the dipstick tube. It does get warm here but no issues so far (Wheel Horse did it this way in 88 and 89 with a less sealed fuse holder). Cleat 2 Share this post Link to post Share on other sites
cheesegrader 433 #7 Posted December 31, 2015 (edited) I have had to replace the fuse block on three of my 520's with individual fuse holders. The heat genrated to melt a fuse will also damage the connectors and wires at the base of the fuse block. I've tried to get by with quick fixes, but none worked until I just cut out the fuse holder and started over. I don't think cleaning the connections is going to be a long term solution. I used solder and shrink wrap on one, but I had issues with an intermittent short, and had to re-do it. Two of mine were done with crimp-on butt joiners, and they have worked fine for two+ years The one that I had to revise is currently in the garage in Wausau. I redid the solder junctions with crimps just in time for the snow this week. Works fine, and plowed all over the neighborhood The fuse order, seat to headlights, is 30 (red/white)/25 (red/red)/15 (pink/pink) There may be a metal link in the bottom of the fuse block between the 30 and 25 amp fuse holder, eliminating the red wire into the 30amp slot Edited December 31, 2015 by cheesegrader 4 Share this post Link to post Share on other sites
