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Cat 345B shut off and won’t start.

Race5118 ยท 2020-08-10 20:24

My 345 is acting up again and I can't figure it out. It was running and it shut off just like the key was shut off. The throttle position indicator on the monitor is showing 00. I went through the troubleshooting chart for it and everything checks out with the dial. It's not getting any fuel it will fire with ether but it won't run. I changed the cam position sensor and swapped the ecm with another known good one. It has plenty of fuel and oil. I'm kind of lost here, any help would be greatly appreciated.

Replies16
  1. #1Race51182020-08-10 21:03

    Also I checked codes on the monitor and I am getting 4207 pumping pressure pwm sensor open circuit during power on and 420E engine speed knob isn't in one of the 10 positions.

  2. #2heymccall2020-08-11 00:25

    Does the hoe have the factory auxiliary hydraulic system with the led panel and buttons in the compartment behind the cab? If so, the throttle goes through that computer, even when auxiliaries aren't in use. It can be bypassed under the cab, but, it has been over 15 years since I had one of them. Water enters the auxiliary controller and screws around with the speed dial outputs.

  3. #3heymccall2020-08-11 00:29

    And, iirc, if that has a 3176 (you didnt bother giving the serial number), the fuel pressure relief valve sticks in its housing (as it wears in/out) leaving you with too high of fuel pressure (which lifts injectors out of their cups), or too low of fuel pressure (which causes a no start).

  4. #4heymccall2020-08-11 00:31
  5. #5Race51182020-08-11 05:18

    It does have the auxiliary hydraulic controller, I haven't ever paid much attention to it but when the machine shut off it didn't seem to be powered on. I thought that was weird but I couldn't remember if it ever had the display on while running. It is a 3176c I haven't ever had any starting issues even after sitting 7 months over winter, so I doubt the fuel check valve is in that bad if shape. I'll read the manual in that auxiliary hydraulic control and see what I can figure out.

  6. #6heymccall2020-08-11 08:07

    On my 3176C in my 4SS 345B, I had 2 injectors lift upwards, bending the hold down bolt. Resealed them all, and new bolts, and less than 20 hours later, same thing. Resealed and new hold down bolts. Then, a no start condition. Upon removal of the check valve plug, the plunger was found to be worn tremendously, and was now stuck open, resulting zero fuel pressure. The plunger wore into the housing. The new one is a full cartridge that puts the plunger inside. I recall easily installing fuel pressure gauge to see the actual fuel pressure.

  7. #7Race51182020-08-11 11:29

    I'll check it out.

  8. #8DEMLONE702020-08-11 13:23

    On the right hand console u have a back up switch for the aux sys . Put in MAN and it would work without problems if u don't use the aux system

  9. #9Race51182020-08-11 17:15

    Found the problem main power relay went bad so no power to ecm or auxiliary hydraulic control module.

  10. #10heymccall2020-08-11 18:56

    ??? Only switch I'm aware off is override? that puts the pumps at a fixed value and requires the adjacent switch to toggle the throttle up and down.

  11. #11DEMLONE702020-08-12 14:22

    U have a switch to override the aux system

  12. #12heymccall2020-08-12 15:25

    Even though I have no B machines left, I would like to learn. Can you show me where the switch to override the auxiliary hydraulics is?

  13. #13DEMLONE702020-08-12 15:49
  14. #14DEMLONE702020-08-12 15:55
  15. #15heymccall2020-08-12 17:56

    My memory may be off, but I don't remember that switch being in any of my 322b, 330b, or 345b machines, all equipped with auxiliary controller as i posted above. I had 9 of them, some to over 20k hours, and I had just about every interior component out of them. Is it possible that was part of a different auxiliary system?

  16. #16heymccall2020-08-12 18:02

    Mine (none of them) had that switch. Again, mine all had the 4 setting, 1way, 2way integrated auxiliary hydraulics. I cant help but wonder if that isn't on machines with just a one way lower tier auxiliary system? Pretty sure that I still have one of those auxiliary boxes somewhere, as they were trouble prone enough that I had to carry one. They were $700 last time I bought one. ++-+--, iirc, got you into the settings.