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D4 7U questions

oldtanker ยท 2015-09-15 13:33

Engine oils for both the main and pony? Can I run 15-40? That's what I fun in all the farm tractors and TLB so it would be great if I could run it in the D4 too. Filter #? Source for things like a PTO setup. Source for manuals. Thanks Rick

Replies5
  1. #1Old Junk Man2015-09-15 17:55

    I run shell rotellat in all my diesel and Gas tractors. The pony engines on the D2 -D4 nd 9U D6 are horizontal and the bores tend to become egg shaped. If they are badly worn you will need thick oil. Ive run them 50-50 with a additive like STP. nothing to clog up. the pony engine on a 7U doesn't even have cam bearings. Cam journal rides in cast iron block. I have a D4 power unit. The same as a 7J dozer 4&1/4 inch bore engine. and the pony was not any good bad crank worn bores . I took off the intake and gutted the block removed the cam pistons and rods. put the heads back on and filled it with 50-50 oil & STP. then bolted a flat plate to the top of the pony. mounted a big one cyl winsconsin electric start electronic ignition engine . I routed that engines exhaust through the intake. ran a fan belt from the one cyl to the pony engines front pulley. and its the best setup I ever used. the winsconsin can run as long as I want. and starts the power unit just fine. Cat pony engines always where tempermental. and the carb & mags are now 50+ years old. You can find manuals for sale on E Bay.

  2. #2oldtanker2015-09-15 18:17

    Thank you. I've had several people contact me about the manuals and I waiting to find out more. That's the oil I run in all my other stuff. 2x Ford 8Ns, Farmall M, JCB TLB and Farmall 1206. Ya I know about old stuff. Both of the 8Ns are 1948's and the M is an early model. Thanks Rick.

  3. #3old-iron-habit2015-09-15 22:43

    A unique solution. Do you have any pictures you can post?

  4. #4moriboy2015-09-16 20:54

    We used to run 15-40 in our old dozers in both the main and pony engines. Never ran into any issues that were oil related.

  5. #5oldtanker2015-09-17 02:16

    OK thanks! Rick