Coolant Leak at Head Bolt?

[knattrass]

Continuing to shakedown the engine in short drives around the 'hood. We noticed a small amount of coolant puddling around the center head bolt between the #4 & #5 cylinders. This center bolt is the rearward attachment for the engine lift hook and is right next to the small cylinder TDC check bolt. Since we know the check bolt is in the top of cylinder - no way it could be the source of leak (right?). We don't recall any passages there, but then again, we weren't really looking that close. Q1-is it possible the check bolt is the leak? Q2-if not, is it ok to pull the head bolt and put more sealant and retorque it (obviously not following the sequence for one bolt)? Q3-the lift hook is bolt straight to the head, no lock washers, right?

[MSeriesRebuild]

Continuing to shakedown the engine in short drives around the 'hood. We noticed a small amount of coolant puddling around the center head bolt between the #4 & #5 cylinders. This center bolt is the rearward attachment for the engine lift hook and is right next to the small cylinder TDC check bolt. Since we know the check bolt is in the top of cylinder - no way it could be the source of leak (right?). We don't recall any passages there, but then again, we weren't really looking that close. Q1-is it possible the check bolt is the leak? Q2-if not, is it ok to pull the head bolt and put more sealant and retorque it (obviously not following the sequence for one bolt)? Q3-the lift hook is bolt straight to the head, no lock washers, right?

Drain the coolant level down some, remove the bolt, clean the threads, apply thread sealant, install & torque. The TDC check plug will not leak coolant (unless you have a serious problem). No lock washers.