50 hr head torque

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    • January 13, 2013 at 3:29 pm #30715
      dogdoc
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        Started the recomended torque check of my Jinma 254, 3 cyl y385 engine.  Bolts 2 and 3 are under the valve rocker arm and cannot get a socket on them.  I tried with a crow foot wrench but with force needed it just wants to cam out.  I really do not want to pull the rocker assembly off.  Can anyone help on this one.

        Thanks

      • January 13, 2013 at 5:00 pm #35598
        ronjin
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          I would take the rocker assy off so that when you do the re-torque you will feel sure that the bolts are all evenly done.

          RonJ

          ronjin

        • January 13, 2013 at 6:18 pm #35599
          Tinbender
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            The rocker assembly has to come off to re-torque the head. If you are uncomfortable doing this you need to find someone who is. Any competent mechanic will have no problem doing this, and with only three cylinders it won't take long.

          • January 13, 2013 at 9:53 pm #35601
            DavidPrivett
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              well if you are torquing the head it is time to set the valves to so it is just a few more steps to get it all done

            • January 14, 2013 at 9:08 am #35602
              dogdoc
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                I live in southern Westchester county NY, with as I joke “winter views of the Bronx”  Tractor mechanics are as common as corn fields around here.  The last time I did valve work was when my dad and I did a valve job on our 64 Pontiac Tempest wagon.  Being the pack rat I am I still have the feeler gauge.  So I guess it is time to cowboy up and get it done.  I've read several protocols and am most concerned about being sure I am at TDC on the compression stroke of cyl #1 at the start, should be down hill from there.

                Thanks

              • January 14, 2013 at 10:05 am #35603
                Carl Darnell
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                  Just putting a click type torque wrench on the head bolts and pulling until it clicks will only tell you if you have a very loose head bolt. If all the head bolts are loose your head gasket is probably leaking. If the bolts don't move and the head isn't leaking your ok. 

                   

                  To really know what the head bolts are torqued to you must mark one hex point and the head surface then loosen that bolt and torque it to the spec. If the point of the hex is before the mark it was over torqued. If the point of the hex aligns with the mark on the head it was correctly torqued. If the point of the hex is past the mark on the head the bolt was under torqued.

                   

                  You don't have to follow the firing order. Just look for both valves to be loose and set them. Turn the crank until you see one cyl with the exh valve closed and the intake open. Turn the crank until the intake valve is closed and you will be on the compression stroke and you can set the valves on that cyl. Do the same with the other cylinders.

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