The other day a fellow employee left the flashers on on the JD 4720 at work. Upon discovering a completely dead battery, instead of charging it he tried to jump start it with a truck. This info has been passed on to me since I was not present at the time. When he turned the key to start, he says smoke came from the right side of the tractor between engine compartment and dash. Now we have nothing. No dash lights, gauges,flashers,zip nothing nada. I've checked everything I could, but it is dead as a doornail. I did find a 30 amp fuse blown and replaced it, but it didn't help. I have power to the ignition switch and starter, but this thing is completely dead. Am I missing a fusible link or in-line fuse, or did he fry the control module. I am at a loss. Anyone out there have a similar problem or an idea where I should look next? Thanks in advance for your help.
Backhoe Uh-oh backhoe no go
- Thread starter GGrip
- Start date
- Views: 2733
irwin
Veteran Member
I'm assuming this is owned by your employer? If so, who is the mechanic for the shop vehicles..you?
No dash lights..lights etc... means an open circuit..could be a fuse, or fuse link.
I suspect the employee crossed the battery leads when he jumped it. If that's the case many things could be damaged including the very expensive engine controller.... but lets not despair yet.
Get out the service and parts manuals and look for and test the starter trigger wire does it have power when key is in crank position? With the key in run position does the related components have power? ... find and check all the fuses, relays and fuse links.. all of them.. you said you found a blown 30a fuse.. where does the power come from to that fuse? You need to get out the test light and trace out the main circuits.
Also find out exactly what the "jump start" guy did .. where did he connect the jumper cables..make him point out the connection points he used.. if it was to the battery make sure he didn't touch something with a hot cable by accident... look for signs of heat damage along the harness and at the connections.
If this is beyond your abilities or comfort level just get it to a trusted tractor mechanic.
Whatever you do.. good luck
No dash lights..lights etc... means an open circuit..could be a fuse, or fuse link.
I suspect the employee crossed the battery leads when he jumped it. If that's the case many things could be damaged including the very expensive engine controller.... but lets not despair yet.
Get out the service and parts manuals and look for and test the starter trigger wire does it have power when key is in crank position? With the key in run position does the related components have power? ... find and check all the fuses, relays and fuse links.. all of them.. you said you found a blown 30a fuse.. where does the power come from to that fuse? You need to get out the test light and trace out the main circuits.
Also find out exactly what the "jump start" guy did .. where did he connect the jumper cables..make him point out the connection points he used.. if it was to the battery make sure he didn't touch something with a hot cable by accident... look for signs of heat damage along the harness and at the connections.
If this is beyond your abilities or comfort level just get it to a trusted tractor mechanic.
Whatever you do.. good luck
Yes it is owned by my employer which is a school district. I have recently been named the "mechanic". I realize the symptoms point to an open circuit. If Arnold the "Governator "would stop trying to balance the states' budget by taking money from education, the district could probably afford to purchase the parts and shop manuals. Unfortunately, time is not on our side ,as this equipment is used daily. No manuals or wiring schematics are available on line so I thought someone might be able to point me in the direction of the fusible links, if they exist. I'm trying to avoid completely dismantling everything searching for something that may not be there( the fusible links). Just a nudge in the right direction will help. I found nothing noticeably burned but cannot see the complete wiring harness. I don't know how much smoke was present or if the tractor started and died, or if he shut it off, or if it started at all. These guys at work are not very observant. They usually hide the broken equipment instead of letting someone know that its out of commission. I'm lucky the even told me about it. I do love a challenge, but these guys take it to another level. Thanks for the input, though, I do appreciate you taking the time to share your knowledge. I'll let you know what I find.
Browsing the on-line parts catalog might help. There appears to be a main wiring harness with fuse block.
This link will take you to the 4720 section of the JD web site. Click on "Parts Catalog":
John Deere products for homeowners: Features for 4720 Compact Tractor (66 hp)
This link will take you to the 4720 section of the JD web site. Click on "Parts Catalog":
John Deere products for homeowners: Features for 4720 Compact Tractor (66 hp)
beenthere
Super Star Member
- Joined
- Aug 16, 2001
- Messages
- 18,512
- Location
- Southern Wisconsin, USA
- Tractor
- JD_4x2_Gator, JD_4300, JD_425, JD_455 AWS, added JD_455, JD_110, JD_X485(sold)
Yes it is owned by my employer which is a school district. I have recently been named the "mechanic". I realize the symptoms point to an open circuit. If Arnold the "Governator "would stop trying to balance the states' budget by taking money from education, the district could probably afford to purchase the parts and shop manuals. ........QUOTE]
Welcome to the forum.
I hope you track down the problem and can get it fixed.
Curious as to why a backhoe tractor is necessary in a school district for education?
irwin
Veteran Member
Hope this helps... this is a link to JD's "Parts look up" for the 4720 .. John Deere - Parts Catalog
Look through the "sectional index" it has some helpful info.
Good luck.. sorry I can't be more help..I don't have the necessary 4720 repair manual.
Look through the "sectional index" it has some helpful info.
Good luck.. sorry I can't be more help..I don't have the necessary 4720 repair manual.
turbo36
Veteran Member
- Joined
- Apr 20, 2004
- Messages
- 1,391
- Location
- Michigan
- Tractor
- JD X739 AWS (3), 2016 Toolcat, JD 2038R
Yes it is owned by my employer which is a school district. I have recently been named the "mechanic". I realize the symptoms point to an open circuit. If Arnold the "Governator "would stop trying to balance the states' budget by taking money from education, the district could probably afford to purchase the parts and shop manuals. ........QUOTE]
Welcome to the forum.
I hope you track down the problem and can get it fixed.
Curious as to why a backhoe tractor is necessary in a school district for education?
Let me guess - doing ground maintenance?
beenthere
Super Star Member
- Joined
- Aug 16, 2001
- Messages
- 18,512
- Location
- Southern Wisconsin, USA
- Tractor
- JD_4x2_Gator, JD_4300, JD_425, JD_455 AWS, added JD_455, JD_110, JD_X485(sold)
Let me guess - doing ground maintenance?
:laughing:
Like a school district shouldn't be hiring out rather than inefficiently trying to do backhoe work ? Bureaucracy at it's best.
I'd suggest promoting private businesses that will hire people to do such work, and leave the education of children be the school district responsibility. That goes with the athletic fields that are so expensive to maintain, with each district trying to get the latest and the best track and field that money can buy (or can't buy seems to be ok too). Sorry for the off-subject post.
joes_427_vette
Veteran Member
- Joined
- Aug 10, 2004
- Messages
- 1,273
- Location
- Midwest
- Tractor
- IH Cub Lo Boy, 955 John Deere , TC 55 DA New Holland, Bolens HT 20 and 1456
Sounds like an expensive day at school. NOW you can hire the professional business to repair the expensive tractor before the smoke turns into a fire later on. I would think a new wiring harness is in order along with associated relays, fuses, and electronics. Good luck and keep the cost down. The teachers need a raise.
The backhoe is used to dig up irrigation lines in the athletic fields. Yes the poor teachers need a raise, but everyone that keeps the system running can do without. I didn't expect to have to endure snide comments or defend my job to those of you who feel yourself superior to a grounds keeper. Don' let me keep you from climbing back on your high horse to look down upon the rest of us. A heartfelt thank you for those with helpful information. To the rest of you dropouts, go back to the shallow end of the pool...