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OLD CAT 4 cyl Grader Running Issue

Discussion in 'Motor Graders' started by Auctioneerhere, Apr 16, 2011.

  1. Auctioneerhere

    Auctioneerhere Well-Known Member

    Joined:
    Jan 26, 2009
    Messages:
    131
    Occupation:
    Auctioneer
    Location:
    Miles City MT
    Ok her it goes, I have had this grader for wuite a while. It ahs always run fine, gutless but smooth.

    Last year I was running it and it just flat ran out of power & I quickly shut it off.

    Fast forward to this year, I changed out the fuel filters, fuel is good, no water.

    It will run, but it is low on power & seems to have a miss. It's kind of a popping sound like a burnt valve...It also is blowing some white smoke.

    It is a 3U series 4 cyl engine, I am guessing it has a bad injector / dirty injector.

    Any advice? I don't have a book so I am not sure if I need a special tool to take out the injector I think is dirty.

    I really don't want to sink a ton of cash into this machine, but at the same time it is so old I feel like I have to keep it going just because.
     
  2. spitzair

    spitzair Senior Member

    Joined:
    May 4, 2007
    Messages:
    960
    Location:
    Squamish BC (Home), Slave Lake, AB (Work)
    I'm not sure what engine you have in there but I'm guessing it's probably similar to what I have in my D6 9U Dozer... I changed the injectors about 8 or 9 years ago when I couldn't get the machine running properly. They were actually quite easy to get out. You undo the line and then there's a big hollow nut holding the injector and a piece of pipe in. Undo the big nut and you should be able to pull the injector and pipe assembly out if memory serves... If it's a D315 engine it should be fairly similar to the D318 that's in my D6... Hopefully somebody who knows more about this will be able to help.
    Cheers!
     
  3. rare ss

    rare ss Senior Member

    Joined:
    Apr 1, 2011
    Messages:
    460
    Location:
    Western Australia
    have you checked the transfer pump pressure?.. if it has a miss you can crack the injector line for each cylinder to isolate the problem cylinder and go from there
    if you have a pre-combustion type head (preheat) the injectors are relatively easy to remove, just give the area and really good clean, remove the fuel line, remove the locking nut if it wont come out you can re-fit the fuel line (and old spare fuel line is handy for this) and get acouple of heel type prybars underneth the nut of the fuel line and carefully pry it out, or if you got a spare old fuel line you can make a slide hammer type injector puller by straightening out the fuel line and threading it through weight with a hole through it and securing the end with a washer and nut or brazed up end ect
    you can use the same technique for a Direct Injection type head but the pencil type injectors tend to be alot harder to get out without a decent slide hammer type injector puller
     
  4. Auctioneerhere

    Auctioneerhere Well-Known Member

    Joined:
    Jan 26, 2009
    Messages:
    131
    Occupation:
    Auctioneer
    Location:
    Miles City MT
    It is not a pre heat type of head, I did crack the lines to isolate what cyl. is missing.

    This is an OLD grader 1950's is my guess.
     
  5. grandpa

    grandpa Senior Member

    Joined:
    Oct 15, 2009
    Messages:
    1,931
    Location:
    northern minnesota
    If you've found which cylinder is giving you the grief like spitzair says and pull that injector. They are pretty straight up to work on..... those needed a long handed wrench to reach down to get on the external bleeds on those old girls tho.
    .