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ReBuilding two 3304’s

Bergz22 · 2020-10-12 09:18

I just received two 3304’s that need new blocks. Serials are 83Z12823 and 83Z12824. AR 1W-3874 I found two blocks on eBay same part number 7N-5454. I see cat has a new number 1N-3574. I’m checking now to see if they are oem cat blocks. I’d prefer to avoid aftermarket. Are there any differences between the two block numbers I need to be aware of?

Replies14
  1. #156wrench2020-10-12 11:20

    just curious, why do they need new blocks?

  2. #2Bergz222020-10-12 11:35

    They each have a hole in it.

  3. #356wrench2020-10-12 13:09

    That's never good. Rod bolts let go or run out of oil?

  4. #4Nige2020-10-12 13:20

    7N-5454 is a counterbored block. 1N-3574 is a spacer plate block that replaced 7N-5454. "How to" instructions attached.

  5. #5Bergz222020-10-12 17:56

    I'm not sure, another company around here got rid of them and gave them to us. They went with new gen sets.

  6. #6Bergz222020-10-12 17:59

    Thank you. I assumed these engines were spacer plate engines.

  7. #7Nige2020-10-12 19:17

    I think you’ll find they are not spacer plate provided that the 7N-5454 block Part Number in your OP is correct.

  8. #8Bergz222020-10-12 19:50

    I’m not doubting you at all. I just assumed they were. We have an older 3304 that is a na pc engine. It has a spacer plate. These are a lot newer, turbo charged, direct injection. I just assumed. Hard to keep track, we have other variants that are the D330, 311’s Getting really tough to find parts for those.

  9. #9Nige2020-10-13 11:43

    Apologies. Just re-read your original post again. Engines 83Z12823 and 83Z12824 were originally built as spacer-plate engines. The cylinder block listed for them is a 7N-6552 but for field replacement a 1N-3574 is called out. The 7N-5454 blocks that you found on eBay are older counterbored blocks. You'd have to check whether it was possible to "backwards engineer" that document I posted above to revert from a spacer plate cylinder block to a counterbored one. You may well discover that it is not be cost-effective due to all the other parts that might be required to go backwards to acomodate the older design of cylinder block. If you want a block that's a drop-in to both these engines then it should be a spacer plate block.

  10. #10Bergz222020-10-13 12:28

    The only reason I was looking for a 7n-5454 is because that is what is cast on the side of the blocks now. I’ll have to double check.

  11. #11Nige2020-10-13 12:46

    Bear in mind that the same casting Part Number might well serve for various “finished” Part Numbers. If the engines are still assembled can you see spacer plates between the head and the block.?

  12. #12Bergz222020-10-13 13:50

    They are both spacer plate engines. What is the point of having the 7n-5454 on the block? Just curious.

  13. #13Nige2020-10-13 15:44

    So you need to look for 7N-6552 or 1N-3574. It's not unusual for various part numbers to be manufactured from the same basic casting, especially in the case of cylinder blocks and cylinder heads. Therefore the Part Number on the casting is not always a guide of what the finished Part Number will be. Confused..? You won't be after the next eopisode of "Soap" (only TV viewers from the 80's will get that one)

  14. #14Bergz222020-10-13 16:22

    Got ya. Thanks for the help.