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Cat d6m dozer engine

jagmohannavindra8 · 2026-03-23 20:45

Hey guys, I’m going to do an overhead on a cat 3116 engine but there is no information plate on the valve cover. Can’t find info on catsis. Can anyone help with the specs on 1.Fuel timing 2.Full load static fuel Dozer S/N 4JN01082 Engine S/N 4TF43807

Replies14
  1. #1HeavyMetalRepair2026-03-23 20:51

    Do you have all of the 3116 tooling? It’s been a while but there was a lot of specific tooling for those. But there was a special instruction in the tooling kit with specs and instructions

  2. #2jagmohannavindra82026-03-23 21:08

    I have a mechanic coming to do the adjustments. He is equipped with the tooling kit and says he’s good with it.

  3. #3Nige2026-03-23 21:10

    I may be wrong but i wasn't aware that fuel timing and full load fuel were part of the overhead.

  4. #4jagmohannavindra82026-03-23 21:33

    There is louder than usual tappet like knocking at idling and also black smoke both at idle and when pushing load. The engine oil and filter were changed last 130 hours and fuel filters also changed. The mechanic suggested that we need to check the valve clearances and fuel adjustment and make sure there within specs.

  5. #5Nige2026-03-23 21:40

    So he was talking about the fuel injector settings in that case, not so.? Unfortunately that information is contained in what's colloquially known as the "0T Spec". It should be on the data plate but in the absence of said plate you'll need to talk to the Cat dealer. Give them the engine Serial Number and ask them to look in TMI for the 0T spec for that engine, then print it out. Sorry that's the best I can do. Note that the 0T Spec is specific to that engine Serial Number. It's not a case of getting "close enough".

  6. #6jagmohannavindra82026-03-23 21:46

    Okay thanks. I will be calling the cat dealer tomorrow. Cheers

  7. #7HeavyMetalRepair2026-03-23 22:21

    He should also check the fuel pressure with a gauge. The smoking makes me think possibly the air fuel ratio controller.

  8. #8jagmohannavindra82026-03-23 22:38

    Okay I’ll let him check the fuel pressure

  9. #9Nige2026-03-24 11:54

    Thinking a bit more about this as a first step the dealer will have to first access the dyno test sheet for the specific engine S/N. The first line on that sheet contains the 0T Spec, it's actually listed as "Spec Number". See the example below.

  10. #10greasynails2026-03-27 06:49

    Timing 2.581 FLS .261 Have you checked that there isn't any compression getting pushed into the fuel rail? These are bad about leaking where the injector hits the cup. Hopefully your mechanic has the tooling to recut the cups and coin the injectors in?

  11. #11jagmohannavindra82026-03-27 20:31

    Thanks for the info on the injector specs. The mechanic placed a piece of clear tubing at the fuel return and there was small bubbles going through at idle and it increases with more throttle. All the fuel lines were checked and no leaks were seen. He said that it was probably the orings that seal the injectors to the cup. We remove the injectors and found that 4 orings were badly damaged and 2 were burned out. I called the cat dealer and they have the orings in stock. He doesn’t have the tooling to cut the cups but can probably get his hands on the tool kit. I have to wait a till Monday to know.

  12. #12greasynails2026-03-29 19:50

    Once these are done properly, the o-rings at the lower tip are actually pointless. You need to cut the taper on the cup so it matches the taper on the injector. The o-ring will make a carbon dam and keep some heat off of the injector, but the actual seal should be a wide section of metal on metal. This is also why you need to coin the injector in. The retaining bolt doesn't have the ability to push the injector in hard enough to deform the cup and make a good seal. You shove it down with the tooling, tighten down the hold down, then let the tooling off. Make sure when you synchronize, you check all the rack linkage for free movement and no worn/loose components. And center the ball in the rack slot so they don't drag.

  13. #13jagmohannavindra82026-04-04 11:13

    I wanted to give an update: The engine is working great now. I had to get another mechanic with the tool to cut the cups and coin the injectors in. Injector and fuel settings were adjusted to spec. There is no compression going to the fuel rail. There is just a little black smoke during hard acceleration but as I understand that is to be expected. Thanks to everyone for their help. Cheers

  14. #14greasynails2026-04-05 20:59

    Good deal. The 3114/3116 gets a bad rep sometimes, especially in on highway apps. As you can see it's finicky to get the top end put together right. If you do it correctly, I've seen these things run a surprisingly long time.