Scarred Push Rod rubbing?

Big Blue24

Big Blue24

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Jan 5, 2008
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When I was replacing the valve springs on my 95' Junker drag truck, I noticed some scarring on the intake pushrod on #3 cylinder. This was the only pushrod with scuff marks and it doesn't appear to be bent. I also checked the valve stem seal and it looks good and valve moves freely.

I put it back together with the scuffed pushrod and the truck runs normally, just concerned for down the road when this motor will have big boost and higher rpm.



Tell me what you guys think.
 
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if you rockers are torqued and valve seats/ valve are ok then your ok almost looks like it was done on the tear down or asy. or clean up process. make sure the pivot balls and sockets are good!
 
Pivots, sockets, and everything looked great with very minimal signs of wear.

Just a little alarming to find one pushrod out of the whole lot with signs of rubbing.
 
also do the drop test, make sure it has a tink tink sound and not a thud if it thuds junk it.
 
It's straight, I carefully checked it out. As far as drop tink vs drop thud, never heard of that one. Maybe I'll have to remove the rocker pedestal and pull the pushrod for a "drop" check.
 
Like forrest said the are cheap. just replace if you have a doubt

My machinest told me about the drop check I cant remember why he said to do it and I know i had a few thud and they where replaced.
 
CL2000 said:
Like forrest said the are cheap. just replace if you have a doubt

My machinest told me about the drop check I cant remember why he said to do it and I know i had a few thud and they where replaced.
Click to expand...

One does this test to be sure the rods are not filled with oil.
 
Roll it on a piece of flat glass, good way to check for straight.
 
I wouldn't sweat it either, the pushrods are actually pretty stout and it probably just got scratched while assembled.
 
What worries me about that picture is the mechanism of damage. I would not just call it good and forget it, something has obviously happened. A fubar happened, and more could be in the wings
I would think along the lines that for some reason the push rod changed its arch. If it’s straight now, its did not heal itself, so it’s not the push rod. So let’s move to the possibility that when installed it was on top of the lifter for a brief amount of time and rubbers , but that would required it to be caught as some time and the rocker relashed.
Next, the possibility exists that the valve briefly stuck open enough that the lash grew to the point that the pushrod jumped up on top of the lifter, or canted to one side so as to rub the wall. There are several reasons that the valve could have stuck open, first a sticky guide, and second a foreign object , could have stuck the valve open briefly .
The drop test is an old deal to see if the push rod has lost its heat treat. The stock push rods are soft anyway, so that is really not a good test.
If this is isolated to one push rod then I would look close, its several, then you need to go with a good set of Chromemolly ones , they are not much more than a set of new stock ones .
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The wear marks are peculiar to say the least.
 
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Is the damage around the height of the Headgasket? I had a bad headgasket once that scuffed up the push rod when some of the material blew out into the push rod hole.
 
The damage does seem to be around the height of the head gasket. The gasket is fine though; who knows what has happened to this motor over the 243K miles it was driven before i bought it!
 
DSC00725.jpg
This is one of mine.I am going to check it again in spring.The marks on yours look to be the same as mine just deeper.
 
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