Komatsu wb140-2

[dirtmonkey]

Guys, I've got a head scratcher here.
Just took delivery on a ( new to me ) 140. Once we got it off the trailer, the battery light came on.
The sellers driver turned the key on and off and the light went out only to come again 20 minutes later.
As I was driving the hoe to its parking spot for the nite, the light came on and the tractor just died in place.
Now, I've good 12.7 volts at the battery, master kill switch, starter,and fuse links ( master fuses 60 amp etc ) and to the relays . All of this is under the hood. Now in cab I have no voltage to the fuse / relay / circuit board. No voltage to the key/ ignition switch ( which I have already replaced).
This thing is dead , totally. No lights , no relay clicking , nothing. I'm at max trouble shooting ability here and just plane P****d off. The seller is willing to work with me to get this going but not till next week and I've got get this thing working. Plus I'm alittle OCD and just want to know what's wrong.
Any ideas :Banghead:bash:crying:cussing


And yes I know , we should have bought a Case but that's another story so please hold those comments for another day. Thanks , Dirtmonkey.

 

[Deon]

Dirmonkey, You just need to walk away for a few hrs or maybe overnight. You probably have a simple problem. Just go to it rested and with an open mind. Check for a ground strap or wire that connects the cab to the tractor frame. Also trace the power wire to where it enters the cab. You may have a large connector entering the cab. Hopefully someone here knows something about your model but your problem is probably just a broken wire or corroded connection.
Be patient and you will find it. You know the saying, the faster you go the behinder you get. Good luck.

 

[dirtmonkey]

Thanks ! You're right , it's gonna be something stupid. Just hard to walk away some times:Banghead
BTW nice paint job ! Looks good :thumbsup

 

[old55pete]

Dirtmonkey, the WB140 is a good machine. I have several customers that have them and love them and say that thye will never go back to Cat, John Deere or Case. That being said, Just like any machine they have their problums. Unfortunatly electrical is one of them.

Start at the starter, there should be at least three, sometimes four wires on the selanoide( sorry about the spelling) a 6 guage wire to the alt, a 2/0 to the Batt and a 10 guage wire to the to the cab. aheck the 10 ga wire and make sure that it is not broke at the starter. then trace it to the fues block in the cab and mke sure that it isent broken or coroded. If that dont work, let me know. I have the maint manual on cd at the shop. We can go on from there. Good luck

 

[dirtmonkey]

Thanks for the reply !. We're good from the starter to the main fuse block under the hood. But , I have no voltage at the fuse/circuit board( under steering wheel ). No power or light on the LED's. What sucks is this thing is stuck out side in the snow and now we' re going to get rain tonight. Can't catch a break!
Btw, I really don't have a problem with the 140's. we had one on rent for along time and liked it. I was hoping to find a used Case because age and parts/experience availability. I feel like we bought a good hoe for price and hours , it's just used and everything that comes with it. But we were ready for that.
I took the day off to clear my head but please keep the help coming. With your help we'll get there. Thank you ! :notworthy

 

[Deon]

old55pete, Can't dirtmonkey use jumper cables of some sort to bring power into the cab to temporarily get it going and bring it in somewhere. If he can get power to the interior fuse board for shifting the reverser etc. then he should be able
to jump the starter and move it inside. What do you think?

 

[old55pete]

Deon, in one word, yes, but dont use jumper cables, kind a like a bull in a china store if you get my drift. Make a jumper wire out of 12 guage wire and run it from the battrie to the back( power pole) of the ignition switch and that will get it going to get it inside to trouble shoot it. Once inside get the loader bucket in the air and secure the safty on the ram. It's a pain in the a............ rear to work on this machine with the bucket on the ground. If what dirt monkey is saying is true, then it is a possibility that the control power circute is faulty and there is no power from the outter fuse/relay box under the hood to the ignition switch as the fuese box in the cab is energised by the ignition switch. I hope that this helps out some

 

[dirtmonkey]

Good morning ! Back at it again. So if I understand you , the fuse board gets power from the the key switch. My confusion is there is no power at all at the switch. Nor the fuse board. Please excuse my ignorance. Is there a fusable link in the system ? Just throwing that out there. :beatsme:dizzy

 

[old55pete]

Yes, there is a fuesable link from the starter to the ignition switch. to check it, use a multimeter or a test light,, it is better to use a multimeter as it will tell you the voltage. test the voltage at the batt first and that plus or minus a volt is what you should have at the ignition switch. if the voltage is good, check the ground. as the dash pannel is plastic there needs to be a good ground from the switch to the chassie. I hope this helps.

 

[dirtmonkey]

Update !!!

:update:update Well it's was something simple and :duh. 30 amp fuse under the hood. Pulled it, could not see the break. But, did not ohm it out :duh :duh:duh. The man that sold it ,came all the way from Texas to do what I should have done in the first place. I should have known better ( damned tunnel vision !). Thanks too all who tried to help and and 100 steak dinners to the man who showed me how dumb I can be ops.
Now I've gotta see what's blowing the fuse. :bash

 

[old55pete]

Good to hear. enjoy your machine.

 

[Deon]

Glad you found the blown fuse. Things are always complicated when you don't know the simple part.
If the fuse blows again you will need to bring it in somewhere and inspect the wires and wiring harness for damage, rubbing etc.
I like to look things over and keep everything in order in hope to prevent unwelcome breakdowns.
It's called preventative maintenance. :beerchug

 

[dirtmonkey]

I hear ya :drinkup. Once I got her going , I started going through the normal drill checking things out. I think I found what's blowing fuses too. The work lights. Once you turn them on ,the battery light will come on. It causes one hell of a draw on the motor. So bad you can hear it. Like an A/C comp coming on. So for now , no work at night till I can rewire.
Thanks for your help and kind encouragement Deon !
Old55pete .. Thanks for your help and sharing your knowledge !
:beerchug

 

[MrKomatsu]

Tunnel vision happens to the best of us........Glad to hear it is working.....