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Munched valve

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  #1  
Old 07-07-2012, 12:04 PM
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Default Munched valve

Munched a valve in the front cylinder of my 49 Pan. Valve was broken off and it embedded on its edge deep into the top of the piston.

Other than the obvious damage to be repaired, what else should be gone over? I've been told that it shouldn't be necessary to go over the bottom end. From looking it over I see little side play on the rods and almost imperceptible to no up and down play on them.

I've got the heads in for repair and complete valve job and ordered new cylinders and pistons. The jugs were already bored out .070 with the front one getting damaged when the valve got munched. I will be checking the push rods for straightness and replacing if necessary.

Is there anything else I need to look into?
 
Attached Thumbnails Munched valve-hpim4236.jpg   Munched valve-hpim4212.jpg   Munched valve-hpim4214.jpg  
  #2  
Old 07-07-2012, 11:45 PM
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Do you know what caused the probelem?

Good that you are cehcking pushrods and such but how do you know (for sure) that metal fragments are not floating in your bottom end/ That sir is some serious &hit. Not sure I would run it without splitting the cases to ensure that metal fragments were not going to cause a soon-to-be motor failure.
 
  #3  
Old 07-08-2012, 02:10 PM
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I believe the problem was a worn out valve guide. Lots of slop. As for the bottom end, nothing got past the piston. All scratches in the cylinder are few, small, and not very deep. piston rings are still in great shape. I did drain the crankcase and did a visual inspection with a flashlight. Found nothing unusual. I think I'll fish around with an extendable magnet to see what might come out.

Spoke with a reputable person with over twenty years of experience working on old Harley motors. He told me not to worry about it. If I decide to do just the top end, I will split the cases this winter.

Thanks for the reply.
 
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Old 07-08-2012, 04:58 PM
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Default oil filter

Does this bike have one ?
 
  #5  
Old 07-09-2012, 07:27 PM
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No, but it will before it gets started again.
 
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