Bad miss or knock... (Video)
- Thread starter 87jumpy
- Start date
I took the fuel rail off and saw this...
#4? Intake Push rod bent.
Can I pull the retainer off, replace the push rod and torque it back to spec or do I need to put the engine in time first?
Would this cause #8 to misfire?
I took the fuel rail off and saw this...
#4? Intake Push rod bent.
Can I pull the retainer off, replace the push rod and torque it back to spec or do I need to put the engine in time first?
Would this cause #8 to misfire?
which valve cover is this?
Charles
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That's what your video sounded like. Classic intake valve sound.
And depending on firing order one cylinder will certainly throw a contribution on another. Hopefully you can replace the pushrod and all will be well. Check that rocker VERY well. I don't know how the 6.4 looks, but on the 7.3 (cheesy rockers I know..) the little "cup" in the rocker at the fulcrum is prone to "crushing". Check things like this as well.
Talk to others who have experience with the 6.4 so you know what the common modes of valvetrain failure are and look for them before buttoning it back up. Check the other cylinders for signs as well.
And depending on firing order one cylinder will certainly throw a contribution on another. Hopefully you can replace the pushrod and all will be well. Check that rocker VERY well. I don't know how the 6.4 looks, but on the 7.3 (cheesy rockers I know..) the little "cup" in the rocker at the fulcrum is prone to "crushing". Check things like this as well.
Talk to others who have experience with the 6.4 so you know what the common modes of valvetrain failure are and look for them before buttoning it back up. Check the other cylinders for signs as well.
Last edited:
Erikclaw
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Damn, that was a little more than just a bent pushrod. Was it driven after you first posted the bent pic?
Nope, pushed it onto a trailer and hauled it to the shop
Charles
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Cracked heads mean little, and the pistons were probably melted for a while. The pushrods were probably all you noticed, and all that needed immediate fixing.
Truck would have probably driven exactly like normal with the other problems, unless one of the cracks went all the way through, or the pistons got down to the top ring.
My heads have been cracked for years now. I don't even bother trying to replace them anymore. They've been back on once or twice after they were taken off and seen to be cracked. Other than welding in seats and grinding them back flush, I don't see a practical solution, so don't see much sense in worrying about cracked heads that don't penetrate a coolant or intake passage. New ones will probably crack again in short order.
Was the compression down? Why did the engine get torn apart in the first place?
Truck would have probably driven exactly like normal with the other problems, unless one of the cracks went all the way through, or the pistons got down to the top ring.
My heads have been cracked for years now. I don't even bother trying to replace them anymore. They've been back on once or twice after they were taken off and seen to be cracked. Other than welding in seats and grinding them back flush, I don't see a practical solution, so don't see much sense in worrying about cracked heads that don't penetrate a coolant or intake passage. New ones will probably crack again in short order.
Was the compression down? Why did the engine get torn apart in the first place?
Charles
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Oh, I got you.
On Edit:
I went back and re-read the first post, and it seemed like everything was cool, except for jumping in the truck one morning and having the classic poop, poop, poop sound out the intake. Unless you were just already planning to pull the heads, I would have probably replaced the bent pushrods and rolled out, lol.
