Got an old Hitachi Grey Market track hoe, 40 UR and it was running fine , everything working 3 days ago but when I went to start it up today, the engine started as usual but none of the hydraulics are working and the Battery light on the console is on. We checked the switch where you lower the left control arm down when getting on the seat and it is working (the engine would not have started if the control arm was in the up position). I checked all the fuses under the seat, no problems so puzzled. It broke down on its own while sitting in the shop for 3 days.. The Battery light being on after starting means some electrical glitch somewhere since the battery is fully charged so could it be some stuck solenoid? I can't even put it on the trailer to take to the heavy equipment shop 3 miles from where it is. Any suggestions on where to start troubleshooting this thing? Thanks, Ray
You will hate this, start a hand over hand inspection of your harnesses, will be a few that run in nasty crud loaded holes you will not want to get into where you will find a Rats nest or Mice or whatever kind of critter has likely eaten thru wire or that a Junction plug had pins turned green. Without Electrical to some machines or under a Fault warning the Pilot system shuts down
Check your battery voltage running
I hear you. i had to replace a steady drip hydraulic hose recently and after removing 6 parts to get to it there was a lot of greasy grime to deal with. We already traced the wire bundles, checked all the fuses and thinking it might be a relay or computer that is under the seat. We carefully checked for wire insulation wear and could find none, no mice nests. The Equipment shop is just 3 miles down the road but can't move the machine on to the trailer but will see if they do Mobile work which i am sure they do since this is heavy logging country and lots of dozers break down many miles from the shops.
Thanks, that was one of the first things we did, runs at 12.4 while engine idling. We noticed there was no voltage going to the two small solenoids mounted on the hydraulics manifold so that might be a problem. That is the only solenoids anywhere on the machine. Will need to get a mobile mechanic out there to troubleshoot it. I am clueless about electrical gremlins, just hate paying the $100 + an hour for chasing these things down. so got all the parts off the machine already so we can access all wires quickly. Might be the relay or computer under the seat.
I have a 50ur manuals that might be help if you like . Whats you email address ?
12.4 is below full charge on battery, at a higher idle speed should be no less than 13.6 or the alternator has quit.
I just had a squirrel eat 3 inches of wire to my 2 speed switch on my cat 304 , pain to find and bigger pain to reach and to fix
How many batteries are in the machine? All the Hitachi machines that I've had anything to do with were 24 volt.
That would be great, might help but the local heavy equipment mechanic thought it had something to do with the Pilot hydraulic pump. $102 per hour but will have to hire him if i want this machine to go again. My e-mail address is [email protected] Does your manual have a wiring diagram showing color codes and in Rnglish...Thanks, Ray
Engine starts up quick, doesn't sound like a weak battery. Would this small drop of volts at start have anything to do with the hydraulics just not kicking on? I can take the alt out and have shop test it, will be a bitch to get off but looks like a bad spot on belt so might as well do that anyway before belt breaks. I also have a higher amp battery that is newer that I can put in. This has only 1 battery, small excavator, around 5 ton.
A good way to test alternator output is to measure the system voltage with the engine at idle and at full RPM. After starting it would not be unusual to see an alternator putting out something of the order of 14.5V in order to charge the battery. A battery in good condition should measure somewhere around 12.8V with the key off.