Working on this backhoe and its has the quick coupler to remotely (hydraulically) release the lock pins and switch between forks or a bucket. There are two solenoids behind the bucket where the fluid flows to before it hits the cylinder. One of those solenoids are electric. My problem is that there is no power going to that electric solenoid. So I hit the switch on the dash and the lines jerk as fluid hits the first solenoid. But the second solenoid isn't opening. I have 3300 psi like I should. I hot wired the solenoid, so I know that works. But I have no wiring schematic and all CAT had to say was they have had a few with a short to ground in the circuit somewhere. SO does anyone have a schematic or know of anything I can try? Where is the power coming from? a coil? PLEASE HELP
Did you find the problem? Is there a ball valve located on the front where the lines are attached? Sometimes the handle/lever for the valve gets bent or broken off and it is hard to spot that there is even a valve there. Not sure what year/ser# yours is so don't know the arrangement. Here is some info that may assist you if problem is still there. (Engage - While the handle for the ball valve is in HORIZONTAL position, the quick coupler pins can be engaged with the quick coupler pin switch. Press the bottom of the quick coupler pin switch (2) in order to engage the quick coupler pins. After the quick coupler pins are engaged, return the handle for the ball valve to the VERTICAL position (4) in order to prevent movement of the quick coupler pins. The quick coupler pin switch should be in the LOCKED position when you are not disengaging the quick coupler pins. Note: Before connecting the quick couplers, you must relieve the hydraulic pressure. Refer to Operation and Maintenance Manual, "Leaving the Machine" for more information on relieving the hydraulic pressure.)
If you want an electrical schematic then please post your machine Serial Number and an e-mail address. You'll have it in your inbox today.
Hey guys thanks for replying. I went in today and bypassed the electric valve and went straight from selector ball valve to the cylinder with the hydraulic line and works fine for the time being. Curbster, I am aware of that ball valve. I make sure the operators are using it as they should be ( as you described). I traced the two 18ga white wires from the valve as far as I could, including under the floor board but from there I didn't have time (patience) to go further without a schematic. Nige, that would be great if you could send that schematic. My email is [email protected] and I will get that serial number to you within the hour. Thanks in advance for all the help guys. Be back soon
Hey guys my email is [email protected] machine info is CAT420D IT S/N BLN10673
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I'm having the same issue with my 420e
Hey Nige. I have the same problem with my 420e it. ser# cat0420ejkmw02860. I would love a schematic or a fix for this problem. email [email protected]