Heavy Equipment Forums Heavy Equipment Community

C9 hole in block. How??

Gingerbeer · 2021-06-11 07:41

Hi guys, Bad day today, grader went down with an oil slick behind it. 140M AWD with a C9. After inspecting we found a hole in the rear rhs of the block. hydraulic oil has entered the block somehow as when running this was mixing in with the engine oil. How does this happen? Any ideas on cause? I know I have a hefty bill ahead of me however before throwing another motor in I’d love to know any ideas on cause?

Replies22
  1. #1Tinkerer2021-06-11 10:59

    I don't know. But I can post enlarged images for a better view.

  2. #2heymccall2021-06-11 12:49

    Only time I windowed a block like that was when the balancer separated, on a 6059 Deere. But, the main cap came out with it (still ran, though). You say hydraulic oil overfill the crankcase. Are any hydraulic pumps timing cover driven?

  3. #3Nige2021-06-11 12:52

    Only real way to find root cause is to tear down the engine and see what’s broke inside. The hole in the block didn’t happen on its own, something inside has given it a bit of a nudge and a hydraulic lock would be at the bottom of the list of suspects unless it was possibly fluid on top of a piston that bent a connecting rod. Piston cooling jet failure and the piston in that hole seized.? Out of interest how many hours on the engine.?

  4. #4Nige2021-06-11 14:58

    A suggestion. Before the failed engine is removed it should have ET hooked up to it and download a Product Status Report. It is quite likely that amongst the Diagnostic Events and Diagnostic Codes recorded in the ECM just at the point where the engine failed is a smoking gun that will point to the root cause of the failure.

  5. #5Gingerbeer2021-06-11 17:08

    13,000hours on the engine. hydraulic oil from the hydraulic tank is going straight into the crankcase and straight out this hole. Thanks

  6. #6Nige2021-06-11 17:41

    It could still possibly be a result of the failure and not the cause of it. 13k and the engine will be getting tired. Engine overhaul on C-Series in graders can be anywhere 14-16k. I still think it will be an idea to get the PSR from the engine ECM before it is removed from the machine.

  7. #7Gingerbeer2021-06-11 17:44

    Yep will certainly get our fitter to do that. Thanks for the comments. Hopefully we find out what happened

  8. #8Nige2021-06-11 17:57

    I’m sure everyone else here is as interested as you are to get to the bottom of it. I’ve seen so many opportunities missed to gather information for failure analysis that I thought the PSR was worth mentioning.

  9. #920/802021-06-11 19:11

    Thanks for posting, interested in your findings causing your C9 to fail, we have had our fair share of troubles with the C9 and C7 engines in our M series graders, keep us informed. thanks

  10. #10Gingerbeer2021-06-13 00:23

    Not many updates other than I ascertained that the block is windowed on both sides.. Still cannot explain how the hydraulic oil is getting into the crankcase, or what would have caused this.

  11. #11Nige2021-06-14 12:20

    I think you'll only get to the bottom of it once the engine is disassembled. Don't forget to have your fitter download the PSR from the engine ECM before pulling it though.

  12. #12Gingerbeer2021-06-14 12:56

    Yep still waiting for our fitters to get out there. Project is in central Australia, 1800km from capital city.

  13. #13N140MM2021-06-22 18:44

    We had a 140M doing that here, it was still under warranty. I think it was 10 years ago so my recollection may be foggy - there is a hose or line that runs from the flywheel housing back to the sump. It had been kinked when it was installed new, and would slowly fill the engine full of hydraulic oil. It was a big bill to fix it, I think the engine or transmission had to come out. Warranty had a fit.

  14. #14Gingerbeer2022-02-16 23:41

    Hi guys, Just wondering if anyone knows if a C9 truck motor block (9DG) would be interchangeable with the 140M Grader motor? Old Motor: TXD00792 Proposed Swap: 9DG10886

  15. #15Nige2022-02-17 10:54

    Are you just proposing to use the cylinder block (and maybe other parts as well) from the truck engine to rebuild your grader engine OR, - are you asking if the truck engine is a drop-in..? The 9DG truck engine is 341 BHP @ 2100 RPM with 1083 ft lb or torque @ 1400 RPM. Your grader engine is 274 BHP @ 2000 RPM with 1052 ft lb of torque @ 1200 RPM. Drop the truck engine into the grader as-is and you are looking at major power train issues. Good news. The cylinder block, crankshaft, camshaft, cylinder head, & injectors are the same between the two engines. Bad news. The ECM, rods/pistons, piston cooling jets, fuel pump, front housing, water pump, turbo, & engine oil cooler are different. Obviously minor stuff such as the sensor arrangement and engine wiring harness will be different.

  16. #16Gingerbeer2022-02-17 17:58

    Nige thanks so much for your expertise and quick response. We have been expecting we would simply bolt on the Grader components, ECU to the bare long block for the Truck motor, and then drop it into the Grader. Hoping that this would suffice?

  17. #17Dave Neubert2022-02-17 18:22

    Looks like a rod came through being on both sides

  18. #18Nige2022-02-17 19:49

    In the words of the famous poet - "T'will not work"........... At least I wouldn't recommend trying it. Why.? The Truck engine rod & piston setup has a 17:1 compression ratio, the grader engine compression is 16.1:1. This will be as a result of the requirement for an additional 70 BHP (almost 25% more) power developed by the truck engine over the grader engine. So if without any changes you try to use the grader turbo and the grader ECM to control the fuel injectors and are pushing air & squirting fuel into the engine that expecting to come across a 16.1 comp ratio it will in fact find a 17:1 comp ratio. That's going to cause all sorts of combustion issues in my opinion, possibly leading to higher than expected exhaust temperatures and all that entails. Valve or turbo failures, etc, would be a distinct possibility.

  19. #19Nige2022-02-18 19:42

    I need to clarify my “rods/pistons are different” statement. More specifically the connecting rod, con-rod hardware, crankshaft bearing, small end bearing, and piston pin/circlips are the same. The piston crown, piston skirt, piston rings, and piston cooling jets are different.

  20. #20Gingerbeer2022-02-20 20:46

    Thanks Nige. Much appreciated your considerate time spent on providing this info. I think we will rebuild the truck block to suit the pistons and rods matched for the Grader application.

  21. #21Nige2022-02-20 21:03

    A wise decision I think. If you need any detailed info on any of the attachments, etc, when you get into the rebuild then please ask.

  22. #22Cmark2022-02-21 00:38

    Look after your old injectors. There's a worldwide shortage of them ATM.