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Cat 299c fuel issue

Clearcut · 2025-10-31 03:30

Hi all. Got a cat 299c. Had a new injector pump and injectors fitted roughly 500hrs ago. Has started getting down in power, not revving to full revs and sputtering like it’s running out of fuel. Only does it intermittently but is getting more and more frequent. Have blown out all the fuel lines, drained the tank. Suspect may be the lift/transfer pump, pump works and does pump fuel but low pressure and sometimes possibly inconsistent flow out the hose. Is there a way to test the pump? Don’t wanna install a new one if that’s not the problem. Can I install a small inline pump to see if that fixes it?? Appreciate your input

Replies6
  1. #1Nige2025-10-31 03:57

    Post a Serial Number please. First step. Have you disassembled the head of the fuel filter assembly and blown through all the passages, including all the screwed fittings, to make sure they are not plugged.?

  2. #2Clearcut2025-10-31 06:07

    Haven’t pulled that apart yet. Serial number jsp02299

  3. #3Nige2025-10-31 06:38

    I suggest you do that as a first step. The contamination from the tank ends often up either inside the fittings or the passages in the head. Remove the pump from the top of the filter housing and make sure the passages in it are clean as well. You may not be aware but the electric pump is only used for priming the system after a filter change or if the machine ever runs out of fuel. There is a mechanical transfer pump located inside the HP fuel pump Assy that has the job of sucking fuel from the tank through the filter during normal operation. See the attached.

  4. #4Clearcut2025-10-31 06:51

    Thanks will try that in the morning, is it possible at all to clean the mechanical pump or it shouldn’t be required?

  5. #5Nige2025-10-31 06:58

    The mechancial transfer pump inside the HP pump is inaccessible and apart from that there are no parts available for it. See the attachment. However take a look at this thread and make a decision whether or not you want to do limited disassembly to inspect the condition of the spring (not available as a spare part from either Cat, Kubota, or Denso) that is known to break. HeavyEquipmentForums

  6. #6Nige2025-11-01 05:18

    To add to the above......... If you discover that the spring is broken replacements are apparently offered for sale on eBay. Obviously non-genuine but at least they are in one piece. Is this it.? https://www.ebay.com/itm/1462486826...IJFrjrWvEP+xbiei2aDuxaRTc=|tkp:Bk9SR4ibvOvHZg