Heavy Equipment Forums Heavy Equipment Community

Cat 730C Engine Issues

ldequip ยท 2025-07-21 20:14

working on a cat 730C (CAT730CLTFF00470). customer had replaced the turbo and said it was smoking badly. He called and i gave a quick look and removed the turbo again as it was leaking oil. not sure if he messed it up but it was a brand new from Cat turbo. the engine did not start smoothly at all with new turbo and could hardly keep itself running at idle. he says it didnt do that before. i gave it a strong dose of injector cleaner and tried again. after 30 minutes or so it cleared up. and i thot possibly but with 15K hours it may need a new set of injectors. it still is not running well. customer says it is making oil -- assuming he means the pan is filling with fuel ... anything else to think of before we go for those injectors? anyone have the tech book for that C13? it does have a jake

Replies3
  1. #1Nige2025-07-22 08:29

    With 15k hours on it I would suggest that the engine is due for an overhaul. At this point throwing a set of injectors at it might fix something but it would be a Band-Aid as far as the rest of the engine is concerned. Has anyone thought about having an oil sample analysed to confirm whether or not the oil has signficant fuel in it.?

  2. #2ldequip2025-07-23 12:31

    Thanks for the reply. Will try to check that out. customer is very optimistic. The truck is overall not terrible when its working.

  3. #3ldequip2025-07-24 23:48

    stopped by the machine today. didnt have a lot of time but checked a few things. Fuel pressure at secondary fuel filter. Engine idling 110psi. Book calls for approx 85 psi. high idle 150 Psi.(book 95 - 105psi) remove fuel return hose no return fuel at high or low rpm. removed check valve where fuel exits head... just a small bit of sludge no fuel. seems we have a blockage of some kind in there.