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CAT 299D3 cranks but no start

ChidJ · 2026-02-05 13:18

Serial BX901588 After googling, it seems like this is a common issue but the associated simple solutions dont seem to be working (turn the key and sit for 2 minutes, put fuel in it, etc) Ran out of fuel yesterday while mulching (gauge doesnt work). Ive had this happen before and it was no big deal. Just fill it up, turn the key, wait for it to prime, crank and go. This time it is not starting. Not sure what to check at this point so I need some guidance. There are no error codes. Just the typical yellow message saying its cold. In the attached picture the yellow arrow points to the lift pump, right? It hums for a bit after I turn the key to the first position as it normally does The red arrow bowl area does have fuel in it. I took it off, dumped it all out and put it back on and it has fuel in it again. Whats next to try? Im deep in the woods with no help but y'all

Replies17
  1. #1ChidJ2026-02-05 13:47

    I've also seen some suggestions elsewhere to "blow out the line". Which one are the talking about? There are several lines into the fuel tank. Attached is the tank diagram.

  2. #2Nige2026-02-05 14:03

    See below. the fuel suction line is #12. It might pay you to blow all of them out in addition to removing the fittings in the fuel filter head and blow through all the passages.

  3. #3ChidJ2026-02-05 14:06

    Got it. Will do. Can I just say, Ive been sitting here shivvering in this CAT thinking, "come on Nige, please be around" haha

  4. #4Nige2026-02-05 14:26

    Also when you put it all back together leave the delivery hose between the filter and the HP pump inlet off then do a couple of KEY ON cycles and see what comes out of it in terms of flow rate. It might also need a filter change if it has sucked debris up from the bottom of the fuel tank. Part Number 541-6596.

  5. #5ChidJ2026-02-05 14:34

    To clarify, the hose I should leave disconnected and monitor is the hose number 1 on the diagram?

  6. #6Nige2026-02-05 14:40

    That’s the one, or at least so it appears.

  7. #7ChidJ2026-02-05 14:55

    All lines blown out. No obvious obstructions. Left hose 1 off. Did a couple key cycles, no flow at all. I put my thumb over the hose end and dont feel any pressure. Whats next?

  8. #8Nige2026-02-05 15:02

    Does the electric priming pump #13 (located directly on top of the fuel filter head) run when you turn the key ON without attempting to start the engine.? It should run for about 30 seconds then stop. If it does run then you need to remove it from the fuel filter head and check there is no debris blocking the passages inside it.

  9. #9ChidJ2026-02-05 15:03

    Yes, It hums along for a bit and then goes silent. Ill pull it off and take a look

  10. #10Nige2026-02-05 15:05

    See reply above. Sounds like there is a passage blocked inside it.

  11. #11ChidJ2026-02-05 15:15

    Here's a picture. Im not sure what its supposed to look like but is that clogged?

  12. #12ChidJ2026-02-05 15:47

    Just took all the little bits contained in the white part of the assembly and cleaned them. We now have flow! Not quite out of the woods yet. I seem to have lost the blue o ring

  13. #13ColdBlackWind2026-02-07 10:01

    When, not if, you get it running my suggestion would be to start at the tank and clean/replace everything between tank outlet and HP pump. I have gone through this. Unbelievable how much trash ends up in the fuel. Good luck.

  14. #14ChidJ2026-02-07 10:33

    Its up and running. CAT wouldnt sell me just the O ring. Said I could only buy the full assembly so I went and got a generic O ring (well a bunch because I didnt know the precise size) and got it sealed up. In the end, I think the little bit of debris in that pickup tube going to the pump was stopping that little plunger from travelling back and forth. She's back up and running just fine. THANK YOU SO MUCH

  15. #15Nige2026-02-07 11:06

    When you get the chance I suggest that you should drain the water & sediment from the fuel tank because that's where all the particles are coming from. The perfect opportunity would have been when you ran it out of fuel but that's gone now. Have to wait for the next time.......

  16. #16HarleyHappy2026-02-07 11:12

    No offense but there should never be a next time to run out of fuel. In all my years working on diesels, running out of fuel always sucks. That and fuel gelling have given me fits over the years. That said, running out of fuel is an operators issue. I try and make sure my fuel gauges all work. Right now, my skid steer is pissing me off because it seems snow collects above the sender and shorts the gauge out intermittently. So I have to run it by the shop and blow off the sender and the gauge works again. Tried siliconing a plug over the exposed terminal but that didn’t seem to work, now going to try and rig up some sort of cover.

  17. #17ColdBlackWind2026-02-07 11:37

    Once I got my fuel system cleaned out I run only fuel that I pump into dedicated containers. I drain my fuel filter EVERY time I use the machine. I keep the fuel tank topped off. I treat my fuel with Clear Diesel. I clean the filter ahead of the lift pump every 8 hours. After replacing an HP pump after 2400 hours at $3000 and seeing the corrosion inside the pump I figure you can’t be too careful.