Kubota L4600DT starting issue

[tammyemond]

I reckon I have to agree, put sme garlic on the seat. it might ward off the evil.
That does not make sense. OPC and Neutral safeties have two separate paths but interlinked. Some relays , I believe is latching but can't unlatch quickly. The OPC has a timer module also. I am wondering if that causes it. Anyway $20 is not bad ivestment for that relay. You can check the old relay against the new one. At least you will have a spare relay for future if your existing is good.

I think he found the problem. The positive battery cable has two wires, the main large wire that goes to the starter and a small wire that is connected with a plug (pictured below). The last two times it acted up he unplugged it and plugged it back in and it started, kinda like it might be vibrating loose. The parts diagram doesn't show that wire and neither does the diagram for the wiring harness so we're not sure where it goes. You said your tractor is similar to ours, I was wondering if yours also has that wire and if so does your WSM show where it goes. The parts diagram only shows battery cable and when I looked up the part number it's $184. Rich was wondering if he could just bypass the plug and connect the wire directly to the battery. Also, I'm going to start a new post, He was driving it home from a field about 3/4 mile from our house he was in high 3rd gear when it somehow jumped into 4WD and locked up the front end and now the 4WD doesn't work. At least it still runs in 2WD so we can still get our jobs done. I'll explain more in my new posting.

 

[JC-jetro]

I think he found the problem. The positive battery cable has two wires, the main large wire that goes to the starter and a small wire that is connected with a plug (pictured below). The last two times it acted up he unplugged it and plugged it back in and it started, kinda like it might be vibrating loose. The parts diagram doesn't show that wire and neither does the diagram for the wiring harness so we're not sure where it goes. You said your tractor is similar to ours, I was wondering if yours also has that wire and if so does your WSM show where it goes. The parts diagram only shows battery cable and when I looked up the part number it's $184. Rich was wondering if he could just bypass the plug and connect the wire directly to the battery. Also, I'm going to start a new post, He was driving ind t home from a field about 3/4 mile from our house he was in high 3rd gear when it somehow jumped into 4WD and locked up the front end and now the 4WD doesn't work. At least it still runs in 2WD so we can still get our jobs done. I'll explain more in my new posting.

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Tammy, I looked at my set up. I basically have a ground battery and do not have that split right at the battery. what I actually have is that split happens right at the starter. There is a split in your case and in my case to feed the dash panel and all the electronics and safeties. The positive conductor to the starter obviously is the thickest dia as it carries a lot of amps during start up. The rest uses battery but there is no rush current involved. Anything passed the bypass is fused below the dash and cowling. I have a copy of battery from Kubota site attached here for your benefit. Like yours it only identifies batter cable and fitting for $184. You do not need to buy that. it does not show if that block is fused. Remove the plug to it to see if there appears any fuse component there. I doubt it very much.
my recommendation is t take positive battery terminal off, wire brush it good and shiny with a dremmel tool and inspect the plug and contacts for sign of rusting. You do not need to remove the plug to by-pass it. just get a short 6'' long, 14 gauge romex cable and connect it to the battery and by pass wire keeping the plug intact.
This probably can be the actual reason that from time t time you do not get juice to the front display panel. You also need to follow that by pass wire from the dide of the engine to where it goes to the front to see if there is any sign of wire being snagged by brush at some point. I think you are on the right track. Good luck to you and hubby.

 

[tammyemond]

Tammy, I looked at my set up. I basically have a ground battery and do not have that split right at the battery. what I actually have is that split happens right at the starter. There is a split in your case and in my case to feed the dash panel and all the electronics and safeties. The positive conductor to the starter obviously is the thickest dia as it carries a lot of amps during start up. The rest uses battery but there is no rush current involved. Anything passed the bypass is fused below the dash and cowling. I have a copy of battery from Kubota site attached here for your benefit. Like yours it only identifies batter cable and fitting for $184. You do not need to buy that. it does not show if that block is fused. Remove the plug to it to see if there appears any fuse component there. I doubt it very much.
my recommendation is t take positive battery terminal off, wire brush it good and shiny with a dremmel tool and inspect the plug and contacts for sign of rusting. You do not need to remove the plug to by-pass it. just get a short 6'' long, 14 gauge romex cable and connect it to the battery and by pass wire keeping the plug intact.
This probably can be the actual reason that from time t time you do not get juice to the front display panel. You also need to follow that by pass wire from the dide of the engine to where it goes to the front to see if there is any sign of wire being snagged by brush at some point. I think you are on the right track. Good luck to you and hubby.
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He said it appears to just be a regular plug, no fuse. The wire goes into the large wiring harness that's at the top of the battery picture so it's hard to tell exactly what's what. The positive cable to the starter looks fine. I'll take a closer look at the plug tomorrow to make sure that there isn't a fuse anywhere in it. If we're not sure, would it be OK to add a fuseable link to the jump wire? Your tractor is so clean, I don't think ours has looked like that since it was new.

 

[JC-jetro]

He said it appears to just be a regular plug, no fuse. The wire goes into the large wiring harness that's at the top of the battery picture so it's hard to tell exactly what's what. The positive cable to the starter looks fine. I'll take a closer look at the plug tomorrow to make sure that there isn't a fuse anywhere in it. If we're not sure, would it be OK to add a fuseable link to the jump wire? Your tractor is so clean, I don't think ours has looked like that since it was new.

I was there when the stork brought my kubota on a crate and I was there when they were delivering it in the shop and actually helped putting it together. My tractor still looks pretty good as it was always barned and I am not making a living using it. I took 100s of pics from all possible angles and directions when everything was open for future reference 11 years ago and to corroborate the info with WSM and Owners manual.

I am 99% that is is just a plug. That conductor serves all but the starting circuit. I would not cut off the plug but keep the plug and by-pass to prove our diagnosis. I think this is a lot more probable cause than the safety switches and the relays. You can add a fusible link if you would like. if you do with the fusible link that is readily available then take the plug out but don't cut it off ( just unplug) and save it in case. The good thing with fusible link is if there is something else that has a short to the ground then it would give more clue if there is anything else. Even with fusible link all the circuit passed the branch circuit are all fused also. See no harm doing it.