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Swapping in a 3306 in place of a D333C in a Cat 977K questions

sawdustmaker ยท 2016-07-18 02:10

I have a '68? model Cat 977k (ser. 11k663) that spun a rod bearing. the crank is pretty well toast. (100 thou under spec). Cat wants an arm and a leg for a crank for this old turd. However, i can get a 3306 pretty easily. from what i can tell they are very similar engines. If i had a running complete 3306 would it basically be a direct bolt up or am i really mistaken? what about accessories?

Replies14
  1. #1tctractors2016-07-18 16:06

    It's an easy swap. tctractors

  2. #2Nige2016-07-18 18:22

    To make things easier I would suggest that you want a 3306 engine from a 977 installation, probably an 14X-prefix 977L, although IIRC even late-model 11K-prefix machines wewre equipped with a 3306. At least that way it would have the correct fuel settings, turbo, and accessories to make it almost a drop-in to your 11K-prefix machine.

  3. #3sawdustmaker2016-07-18 20:12

    Thanks for the help. I hope I can find one out a 977. Does anyone know if the injection pumps bolt up the same? If so, could I use my pump and turbo?

  4. #4Jimbo2016-07-19 12:25

    Not much help, but I have actually seen a 977K with a 6-71 Detroit stuffed into it as a replacement motor

  5. #5oldirt2016-07-20 11:45

    now that would be a rather large step backwards..

  6. #6seatwarmer2016-07-20 12:11

    Eish , the diesel to noise convertion would be great

  7. #7sawdustmaker2016-09-06 22:44

    Im having trouble finding info on the original motor. From what i can find it was 10.5 liters, 170 HP at 1800 rpm and 5?0 ft/lbs of torque. Does anyone know what the no load rpm is? Or have an educated guess... Any other info would be appreciated.

  8. #8Cmark2016-09-07 00:56

    Scrape the paint off the top of the injection pump around the fuel lines and see if there are any numbers stamped there.

  9. #9sawdustmaker2016-09-07 01:41

    I dont see anything. You mean here? View attachment 158565

  10. #10Cmark2016-09-07 02:05

    Bad link

  11. #11sawdustmaker2016-09-07 02:11

    ill try again.

  12. #12Cmark2016-09-07 02:33

    Yes, on that machined surface around the four injection lines. Looks like yours is pretty rusted though. The marks will be faint. You will have to clean it to bare metal with a scotchbrite pad or similar. You are looking for a number, then a letter, possibly T, then another four numbers. *T****.

  13. #13sawdustmaker2016-09-07 02:58

    I don't see any numbers.

  14. #14Cmark2016-09-07 05:19

    Thats a shame. It would have made the job simple. Unless anyone here has a better idea, you will have to find someone at your local dealer who is willing (and has the knowledge to) dig out the old microfiche reader and boxes of films to look up the information for you. If you're polite but insistent, you should be able to get what you want. It is a Cat product and the info is out there.