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2011 Cat C4.4 low oil psi warning

willw · 2021-10-14 06:11

I recently purchased a chipper with a Cat C4.4 tier 3 Diesel engine serial 44408717. The issue I am having is at idle when hot the low oil pressure warning light comes on for the psi being 14 at 775rpm. At 2400rpm I have around 50psi. The psi spec I have for the engine is 43psi at full throttle hot. I don’t have an idle spec. When I bought the chipper the engine was partially assembled original owner had mechanic pull apart for the low oil psi code. The rotating assembly was together with new pistons and bearings. I finished reassembling the engine with a new oil pump and new relief valve. Following the troubleshooting tree I have replaced the engine oil cooler for good measures because I couldn’t really see a way to flow test it. This made no difference in the oil psi. I have over filled the crankcase by a gallon to see if I had a suction problem and that also made no difference. I guess what I am asking is has anyone had issues with the c4.4 or Perkins base engines that would cause low oil psi before I remove engine and disassemble to mic crank and check cam bearings and maybe idler gear bushing?

Replies10
  1. #1heymccall2021-10-14 09:33

    Cut open oil filter. Just spent $22k on c4.4 in my 506 hour, 2011 bandit drum chipper. Unit has oil pump in assembly with counterbalance shafts. One bushing on the counterbalance shaft that also has oil pump goes south. The counter balance shaft then "leans" putting the oil pump innards against the side of the case. Either way, shut it down.

  2. #2willw2021-10-14 09:52

    I don’t have the original oil filter from last owner but saw no signs metal in the system. When installing the balancer shaft assembly it spun free and didn’t seem to have play in the shafts. The oil pump in the assembly didn’t look worn but I replaced it and the relief valve for good measures. Again not seeing any sign of contamination. When you say “leans” into the housing, will the pump wear into the 4 bolt pump cover or into the housing assembly? I do think I will be pulling engine and inspecting everything closer just want to exhaust all other options while engine is together running. Thank you

  3. #3DB22021-10-14 09:56

    Honestly at that point I would be looking at a repower. We have one of those C 4.4’s and the parts are ridiculous. It’s gonna get a Cummins BT 3.9 pretty soon. Only because I have a couple that were salvaged out of other equipment.

  4. #4willw2021-10-14 16:46

    What are you seeing for oil pressure at low idle and high idle with the c4.4s you have? Just wondering what normal is.

  5. #5DB22021-10-14 18:46

    I can check next time we have it running.

  6. #6heymccall2021-10-14 20:14

    The same paddle balancer shaft that goes to oil pump, on mine, failed the bushing on the end toward the flywheel.

  7. #7DB22021-10-14 20:34

    With only 506 hours ?

  8. #8willw2021-10-14 20:38

    Pulled the pan down tonight and I don't feel any excessive wear on the balancer shaft bushings when trying to wiggle by hand. I plan on getting plastigage tomorrow to check mains and rods. I have an electric pump that I hooked up to the filter housing to try pressurize the lubrication system with oil. With the pan off all mains and rods seemed to have comparable leakage. Only thing I did notice was more oil coming from timing gear train area than any rod or main bearings. I've never seen an oil system with the pan off and didn't know if this was normal or if I should be looking into cam bushing or idler gear bushing. The balancer shaft seemed to have comparable leakage at all for journals.

  9. #9heymccall2021-10-14 22:09

    Yup, 506 hours. Special order that canceled in 2010, then a handful of short term rentals, then we purchased it in 2016. Morons didn't see the 34 low oil pressure events because the Murphy display self destructed, and no one said a word. I had a chance at Cat goodwill until the ecm report.

  10. #10DB22021-10-14 22:34

    Ouch