IthacaJeff 151 #1 Posted May 27, 2020 HI folks: Got an interesting situation, I've not seen before. Began blowing 15A fuses -- standard blade type -- in my 416-8. At first I checked all the grounds I could, things seemed okay. But then today, I noticed that the fuses would blow (3 times) only when under load. I'm pulling a spring tine harrow drag through the garden and normally things are good. But then the drag hangs up, the Kohler goes under load, and then the fuse blows and the tractor stalls. BUT. . .if I lower the throttle to idle the engine will remain running. If I increase the throttle the engine will stall. The fuse is indeed blown. Thoughts? Share this post Link to post Share on other sites
squonk 41,737 #2 Posted May 27, 2020 (edited) What is the fuse actually for? The only thing that will blow a fuse is too much amperage. A short to ground will allow to much current to flow. An electrical circuit like say a stator winding that gets hot can expand enough to touch it's frame and short. Also if that same winding is comprimised it's built in resistance may drop causing increased current flow causing a fuse to blow. Another thing to check is for is the fuse holder. I know 520 fuse holders get all kinds of crap in them grass dirt ect. Blade fuse are really susceptable to bad connections in the fuse holder. Bad connections cause heat. Heat = current and fuses will blow. Edited May 27, 2020 by squonk 2 Share this post Link to post Share on other sites
IthacaJeff 151 #3 Posted May 27, 2020 (edited) According the wiriing diagram there are only three connections through the fuse. One is to the seat switch, which as been disabled for at least a decade, the next is to the solenoid, and then the next seems to be in contact with some DC voltage coming off the alternator. I'm a bit confused by that last connection, though it is part of the hidden away tangle of wires that I have not fully investigated. The fuse holder is held to a metal rail by way of a metal spring clip on the fuse holder. I just pulled the fuse holder off the rail and got a small spark. That does not seem normal. Is that metal spring clip serving as a ground ?? Does not seem right. Not sure why a bad fuse holder would fail when the tractor was under load. ???? Before I replace the holder I need some insight if the spring clip is a ground or simply a clip. Thoughts? Edited May 27, 2020 by IthacaJeff Share this post Link to post Share on other sites
squonk 41,737 #4 Posted May 27, 2020 Could be because the engine would vibrate somewhat under load and possibly that wire is rubbing on some metal. I would investigate that wire. Also even though that seat switch is disabled, that wire to it may still have power on it and can be rubbing somewhere on it's way to the seat 1 Share this post Link to post Share on other sites
IthacaJeff 151 #5 Posted May 27, 2020 Sounds like a plan, Squonk. I'll give it a shot. Share this post Link to post Share on other sites
Tractorhead 9,065 #6 Posted May 27, 2020 Did you looked if throttlelever will hit a wire in full throttle position? Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,148 #7 Posted May 27, 2020 A wiring diagram Share this post Link to post Share on other sites
squonk 41,737 #8 Posted May 27, 2020 The diagram Garry provided shows the headlights on that fuse also. Very likely culprit. Wire runs up to the hood. Heat and vibration. I've seen shorted light sockets and even the bulbs themselves. Share this post Link to post Share on other sites
kasey54 305 #9 Posted May 27, 2020 The spring clip on that fuse holder should no way spark. Could be all your trouble right there. 1 Share this post Link to post Share on other sites
squonk 41,737 #10 Posted May 27, 2020 7 minutes ago, kasey54 said: The spring clip on that fuse holder should no way spark. Could be all your trouble right there. If there is a completed circuit with power present in one clip, yes it will spark. If there is a reduction of resistance in the circuit (short to ground ) The fuse may actually blow as you insert it. Share this post Link to post Share on other sites
kasey54 305 #11 Posted May 27, 2020 I assume he meant the clip that fastens the fuse holder to the chassis. Maybe I misunderstood. Share this post Link to post Share on other sites
kasey54 305 #12 Posted May 28, 2020 I think there are two issues, #1 the blown fuse. #2 engine quits at full throttle , but runs at low throttle with blown fuse. Share this post Link to post Share on other sites
IthacaJeff 151 #13 Posted May 28, 2020 Thanks, folks. I think I found the culprit. Even though the seat safety switch was removed a decade ago and the wires tied together, the wires were frayed. I simply wrapped those up. For good measure I used electrical tape to isolate the fuse holder clip from the chassis. Don't know if that would do anything, but couldn't hurt. I'm not sure why this would only solve the problem that only seemed to come when under load, but it could have to do with more shifting and the tractor jerking on the drag chain. Regardless, no problems with pulling the drag for more than an hour. 2 Share this post Link to post Share on other sites
