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Any tricks to up the HP of a D343 Cat?

Hallback ยท 2017-11-11 20:17

Trying to squeeze a little more horsepower out of our yarder. Anybody have any tricks to get these things to crank up?

Replies9
  1. #1Junkyard2017-11-11 21:09

    Nitrous! Lol jk. First make sure overhead is set right, fuel pressure is right etc. If I'm not mistaken you can adjust various things pump wise that will give it a little more power. Governor, maybe timing, air fuel control. I'm not intimately familiar with them but I'd imagine it's similar to later model Cat mechanical stuff in that regard. I know you could tweak on the old 1693's. I know when we'd turn one of them up we'd look for a good chocolate brown smoke and we'd stop there. If they're like the 93's, 3406A etc they don't like to run very hot. 160-180 IIRC.

  2. #2old-iron-habit2017-11-11 23:13

    Ask your question on the ACMOC site. A few Cat mechanics frequent there that worked in HP increases and factory upgrades.

  3. #3Hallback2017-11-12 07:22

    Thanks guys! It is a really good running old girl and I just need a few more HP out of her. Don't we all? Old iron, what site are you referring to?

  4. #4John C.2017-11-12 11:08

    ACMOC Antique Caterpillar Machinery Owners Club. http://www.acmoc.org

  5. #5old-iron-habit2017-11-12 17:48

    As in post above. Quite a few members up in your neck of the country to. Many of the HP tractors are in the western part of the country mostly to pull Ag equipment faster.

  6. #6Bluox2017-11-12 21:22

    Try the easy stuff first,change fuel filters, air filter,clean the primary screen and check fuel tank. If the transmission or torque convertor oil and filters have not been changed lately that helps power wise. Any idea how many hours on the engine?Before you start changing fuel settings be aware these engines will burn down if they are over fueled.You need a boost box and a photo-tach to check engine settings.You also need to know what engine you have, fuel systems are somewhat different.But I guess the main question is how fast do you need to pull out stumps? Bob

  7. #7Hallback2017-11-12 21:43

    Ox, Those are all very good things to check IE the primary screen transmission filters Etc. Regular fuel filters get changed often but digging deeper will probably help

  8. #8Bluox2017-11-12 22:49

    Had one yarder engine lose power start black smoking finally discovered the chaser sat on the air cleaner lid to eat lunch and the lid slid down the pipe cutting off the air to the filter. Had a 343 engine start running bad found the quill shaft on the cam drive twisted changing the timing. So weird things happen. Good luck Bob

  9. #9Fuel Oil2017-12-09 18:46

    Pre cup engines frequently crack pistons when over fueled, just be careful how much you turn it up.