546cowboy 301 #1 Posted May 15, 2009 Hi there I have a 1990 520H that I bought with a blown engine. I found an engine and have it running now but the gas gauge,amp gauge and tachometer don't work. The hour meter works fine. I have downloaded the wiring schematics but they aren't very good and the wire colors don't match what's on my tractor. Has anyone had a similar problem? Any help would be appreciated. Share this post Link to post Share on other sites
Bow_Extreme 534 #2 Posted May 15, 2009 The 520H wiring schematics can be difficult at some points to understand but they aren't too terribly bad to deal with. Number one, are you sure you have the correct wiring diagram for your tractor? usually the best diagram is located at the end of the tractor manual for your model number and serial numbered tractor. the reason some of the colors may or may not make sense is because some of these wires are one in the same, just different colors in different segments but yet they are one segment, if that makes any sense. The wiring at the gauges is usually very accurate. It's just time consuming and tideous to trace all the connections down. Verify your info and take your time. It's not too bad of a job in the end. It's sometime's easier to open up the wiring wraps ( not the sheath that cover's the wire but the harness wrap that usually keeps all the wires bundled together. This allows a full inspection of each wire and connection. Remove all connections where necessary, clean, inspect, test, and coat liberally with di-electric grease. Make sure when your all done to re-wrap the harness wiring for a nice clean look and to prevent future damage from occuring. Goodluck!! Share this post Link to post Share on other sites
04fxdwgi 0 #3 Posted May 16, 2009 Hi there I have a 1990 520H that I bought with a blown engine. I found an engine and have it running now but the gas gauge,amp gauge and tachometer don't work. The hour meter works fine. I have downloaded the wiring schematics but they aren't very good and the wire colors don't match what's on my tractor. Has anyone had a similar problem? Any help would be appreciated. Cowboy, I am looking at the diagram and the only thing common to all the gauges EXCEPT the hour meter is the ground wire. Looks like you have a broken / bad ground. Try using a jumper from negetive battery terminal to the gauge common ground on anything except the hour meter. That should get them to work. Good luck Bill Share this post Link to post Share on other sites
Kyforeman 0 #4 Posted May 16, 2009 I would look close at the ground wires as well as there are two that attach right under the fuse block and I think if memory serves me right the bolt also holds down the micro safety switch for the PTO lever. It seems that a lot of the 520's are plagued by wiring issues. On mine I had problems such as your and others where the previous owner had cut the engine harness in two and was going to try to use the big Onan in one of the Green Tractors. His luck ran out there as the crankshaft was different and I was able to get my 520H for a great deal less. It took a little work to repair the wiring but it was really worth it. I had a lot of help from Bow Extreme and had it up and running fine in a day after tracing the wiring out and making the needed repairs. On the tachometer, make sure it is hooked up correctly off of the voltage regulator as its easy to get it switched around there. Mine has a Volt gauge instead of an Amp gauge so my Wiring would most likely be a bit different, but if your is a Volt gauge, make sure your connections at the 9 wire engine harness are clean and tight. As Bow Extreme said above some of the wires do change colors and the one coming form the charging system is one such wire as it goes from a red to a white on the block, and the white on the other side of the connector turns into a purple on mine. I ended up taking the 9 pin block off completely as it had overheated from a few wires there being loose. The fuel gauge I can offer no opinion on as that's the only one that worked on mine in the beginning. I'm sure you can find your problem if you keep looking and if not just get back o here and someone will be more than glad to help you figure the rest out. Lastly to the Best Darn Wheel Horse board on the net. Also we like pictures so get some pictures as we don't see as many 520's as the others it seems. hope you get it straightened out and have a Great Weekend. Greg in Kentucky.. :omg: Share this post Link to post Share on other sites
Raider12 13 #5 Posted May 17, 2009 You mentioned you found a replacement engine for this 520? From my understanding, you have to have an Onan engine for the Wheel Horse in order to have all the bells to work. I may be wrong here, maybe someone else can add to this? Share this post Link to post Share on other sites
