2006 Branson 4720i won't start...head scratcher.

[Texas Tractor]

HI newb to this forum, not to tractors, I own a 2006 Kubota L5030 w/backhoe bought used and 2006 Branson 4720i which I bought new has been a great running tractor with few issues over the years. Until last week wife was running it with a roller pump spraying our pecan orchard, she parked it for a break, went out to start it and it was completely dead.....Fast forward today, I've been working on it all day. Battery is about 85-90% at 12.47 volts, turn the ignition on, no lights, no fuel pump sound, no dash lights...nada....so I went through the fuse box checked every one of them, pulled the dash apart ohms checked the ignition switch, verified battery voltage at the ignition switch affirmative 12.47v....went through all the electrical connections under the dash pulled apart and cleaned them. Went back to the battery verified ground to frame and engine has good connection by ohms and voltage check. went to starter same results, pulled the fuse box, ground fine. I suspect it is an open circuit somewhere in the wiring loom, like a broken wire or perhaps a bad relay, or maybe usable link? Just spitballing right now. I'm kind of at a loss of what to check next. Any advise would be greatly appreciated.

 

[grsthegreat]

is there a master fuse on that machine. most tractors have them and alot of times there located near the starter.

possible a fusable link like this

Fuse And Fusible Link - Branson 00 Series Operator's Manual [Page 139]

Branson 00 Series Manual Online: Fuse And Fusible Link. When replacing the fuse, use only one of the same capacity. WARNING Stop the engine and check the main fuse(fusible link). Open the fuse box cover and check the fuses. Replace any burnt-out fuses with new ones of required...

www.manualslib.com

also , is that a battery voltage under load? have you tried another battery. i havwe had lots of batteries that show 12.5V + under no load drop to nothing under a load. i myself have a carbon pyle tester and a midtronics battery analizer. id be lost without them, as i service lots of generators with these ghost problems like your tractor

 

[Texas Tractor]

is there a master fuse on that machine. most tractors have them and alot of times there located near the starter.

possible a fusable link like this

Fuse And Fusible Link - Branson 00 Series Operator's Manual [Page 139]

Branson 00 Series Manual Online: Fuse And Fusible Link. When replacing the fuse, use only one of the same capacity. WARNING Stop the engine and check the main fuse(fusible link). Open the fuse box cover and check the fuses. Replace any burnt-out fuses with new ones of required...

www.manualslib.com

also , is that a battery voltage under load? have you tried another battery. i havwe had lots of batteries that show 12.5V + under no load drop to nothing under a load. i myself have a carbon pyle tester and a midtronics battery analizer. id be lost without them, as i service lots of generators with these ghost problems like your tractor

Unable to test the tractor under load as it won't complete the circuit when the key is turned, it acts like no battery connection at all, which is why I pulled the dash apart after verifying I had at least enough voltage at the battery that I should get a click or lights, or some kind of indication that the battery has power, as I mentioned won't even show dash lights , no horn, no headlights, flashers or anything. I have my 200 amp battery booster hooked up and still got nothing. I used my Fluke 87v Max to test the battery, so I know it at least is accurate under no load. I had a similar issue a few years back, but it ended up being a ground on my fuse box. Im not sure about any master fuse. Ive been tracing the wiring loom looking for broken wires bad connections etc...I do have one main connector that has about 15 wires going through it, I may need to replace it, because when I attempted to disconnect it, it started to break, guessing the old plastic couldn't take the heat, its next to the engine above the starter. Im worried that might just be the issue, will be a PITA to replace.

 

[Texas Tractor]

Update...succesful attempt at wire tracing. I found a connection right above the problem deteriorating cluster connection of wires that had electrical tape on it, I. exposed the connection and for whatever reason it had worked its way apart. I reconnected the wire and now have lights. Came in for a break to update the problem is solved, I have to go back out and put everything back together. Glad I will have more years of use for my tractor, was getting close to dammit wrench tossing...

 

[grsthegreat]

glad to hear

 

[Slowpoke Slim]

Glad you got it fixed. Thanks for the update. Maybe it was just vibration over time? Or was there corrosion in the connection too?

 

[Red_rider]

This kind of problem can drive you crazy. In the 18 years I've had my 3510 there have been 2 occasions where I was out working, shut the tractor down for 10-15 minutes, came back and it wouldn't start. Every time it has been a ground issue, usually to the frame. Yesterday it happened again, but this time it was the cable on the battery post. It wouldn't tighten enough to keep it tight (original cable) so I replaced it with one I had for one of my antique cars - 12 volt of course.

 

[grsthegreat]

I purchased a brand new set of cables for my tractor, cause the original set is as tight as I can make it. The lead clamps do tend to stretch. Next time I replace battery I’m installing the new cables.

 

[Branson Bob]

I purchased a brand new set of cables for my tractor, cause the original set is as tight as I can make it. The lead clamps do tend to stretch. Next time I replace battery I’m installing the new cables.

I suppose it would be possible to get some lead sheeting and make some cylindrical sleeves to add some girth to the posts. It would be cheaper than new cables anyways and the conductivity should work fine. Just a thought.

 

[LouNY]

The battery cables that clamp shut with a thru bolt I have been know to remove the bolt and squeeze it shut then use my hacksaw to cut the slot, repeating a couple of times then opening back up and they will clamp down nice and snug again.