I have a cat E 120 B that has been very good to me until now.The machine has sat for about 3 months and when I went to start it the batteries were dead.Note: One battery is 4yrs old the other is 1yrs.When I had them load tested they said the just needed to be recharged.So I did just that and put back in and the machine seems completly dead.Not even power in the cab.Anybody else run into this problem?
I hate to suggest the completely obvious, but since you've had them out and put them back in, are all the connections good and clean and tight?
Every thing is clean and tight.I just tried both batteries in my Backhoe and the start it just fine.What are some common probs to have between the batts and the cab?When I put the key to the on position I have no power at all,lights etc!!
starting problems most excavators now days have whats called a battery relay (ie) electicial controled master switch somewhere close to the batterys check that then start looking into the wireing should be one small wire to supply the switch then it actavates the relay and turns everything else on. There is also a fuse for that circuit. If that all ok then start looking for broken or chewed through wires
Your biggest problem is your batteries NEVER EVER run a old battery and a newwer battery together and expect the machine to start. You need to replace both batteries with new ones. A battery that is 4 years old is junk I don't care how good you charged it. The 4 year old battery draws juice out of the 1 year old battery and drops your voltage way down. Low battery voltage will kill your starter which will cost you a bunch of money and frustration getting it repaired.
Check the ground, ground the batteries direct to the starter with jumper cables to make sure you have good ground. No power at all, no lights etc sounds like a ground problem or in line fuse. They are around the battery and are much larger than car fuses sometimes 50 to 60 amp. Also check ground cables and wires for rodent eating wires.
Thanks for the advice Ford Lt-9000!!So what you are telling me is NEVER EVER run a old battery with a new one because this will cause me to have no power in the cab even when both batteries are charged.I do thank you for the advice but not the dad attitude.Please keep your advice more on the positive side.I do understand what you said but that is not the problem!If I am reading you wrong I am sorry,if not please find someone else to belittle.Thanks for all the feedback from everyone else so far!!!
I have been pulling wrenches for a long time and any time I hear people with starting problems is from batteries. If you can reach the starter cellenoid short it out to see if you have any juice to the starter. Are you sure the machine doesn't have a night switch that maybe you don't know about but someone else seen it and turned it off ? Its hard to describe to look for maybe when you took the batteries out you accidently bumped a wire and it broke off and come loose. Oh ya I didn't mean to belittle anybody but its common knowledge to never run a old battery with a new battery.
Do you need two keys to start it?Most of the Cat stuff has that master key that looks like a pickle fork,can it be a simple thing like that?I don't know what an E 120 b is but if you have not run it for three months you could overlook something like that.I am not trying to insult you,we all need some help once in a while. Ron G
Thank you all members for the advice given.I tried the trick that jmac suggested and the machine fired up.Now my machine has a relay that the ground from the battery goes to.I will order a new one as it seems to be the problem I hope?It smelled a little burnt when I took it out to clean it up.Has anyone had a problem with this and also what is the function of this relay?Thank you again for the help everyone.
Relay The relay you are talking about is the battery relay (see post above) it is used as a master switch and they do go bad it is just like a large starter selonid in side.