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3306 Rocker Arm issues

cinahcem · 2024-07-22 12:32

Hi I have a D6R LGP with a 3306 in it that i am seeing for the first time. The engine had blew a head gasket and when i went to put the rocker shaft back on i had noticed that the plug on the back mount bracket was missing so i am not sure if it is supposed to be in there. The serial number of the engine is 08Z99534. If anyone has any info on this that would be great. I can't imagine it has ran this long without it, but it could have rattled out and is now in the pan.

Replies15
  1. #1pumkinhead2024-07-22 13:13

    plug 5?

  2. #2Nige2024-07-22 13:57

    Yes and no. Engine 08Z99534 relates to machine Serial Number 9PN00598. If that machine S/N is correct then the rocker shaft and fittings are as per the attachment. The plug for that arrangement is a 3K-8460.

  3. #3cinahcem2024-07-22 15:51

    No not that one, This plug here

  4. #4cinahcem2024-07-22 15:53

    That’s correct the d6r serial number is a 9pn00598, the weird thing is it wasn’t in it but yet the machine has been running for god knows how long and there is no wear on the rocker arms

  5. #5Nige2024-07-22 16:14

    Is that threaded hole a 1/2" - 20 TPI by some chance.?

  6. #6cinahcem2024-07-22 16:29

    Correct, in the parts book it says 1/2”-20 thd, not sure what the is

  7. #7Nige2024-07-22 16:38

    That's for the 3K-8460 plug which is a serviceable part of the 7C-7011 Bracket Assy #1 Article annoucing the change attached.

  8. #8cinahcem2024-07-22 16:44

    So the strange thing is this dozer came in for a blown head gasket and that plug was missing, I can’t imagine how the front rockers never seized up

  9. #9Nige2024-07-22 16:45

    The oil pump must have plenty of extra flow capacity is the only answer I can think of.

  10. #10cinahcem2024-07-22 16:47

    Yah for sure, well thanks for the help

  11. #11cinahcem2024-07-25 13:51

    Strange question but on this engine would you get a fuel knock from the pumps if your absolutely sure and injector nozzle was good?

  12. #12nicky 68a2024-08-05 13:40

    I know nowt about these 3306’s,but those rocker shafts do vary abit between applications. I’d hope the rocker is the precise part number for the particular engine or oil starvation can occurs as the oil holes are abit different on them. Be sure it’s getting enough oil dribbled out on all rockers

  13. #13nicky 68a2024-08-05 13:47

    Am I correct in thinking you’ve bought the D6 with a head problem? Is that the correct rocker shaft I wonder? Have they swapped it before giving you the job? It’s worth checking

  14. #14cinahcem2024-08-25 12:35

    I think it was an updated rocker shaft as this machine has 19000 hours on it

  15. #15cinahcem2024-08-25 12:36

    I think it was an updated rocker shaft as this machine has 19000 hours on it