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#Post#: 13774--------------------------------------------------
Piston Failure Analysis
By: Chainsawrepair Date: December 12, 2012, 1:32 pm
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Piston Failure Analysis
Just a little guide to help people out. In 2 links to read
below in this post.
#Post#: 13776--------------------------------------------------
Re: Piston Failure Analysis
By: davbell22602 Date: December 12, 2012, 1:40 pm
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[quote author=Cut4fun_ link=topic=1377.msg13774#msg13774
date=1355340734]
Piston Failure Analysis
Just a little guide to help people out. Should be 2 links to
read.
[/quote]
Thanks for sharing that info.
#Post#: 32884--------------------------------------------------
Re: Piston Failure Analysis
By: Chainsawrepair Date: January 27, 2014, 1:11 pm
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What do you think? Aftermarket P + C on 360 intake side. He
says exhaust side looks good. Ate something? Says crank
bearings are not loose, but are not very smooth.
[img width=525
height=700]
HTML http://img.tapatalk.com/d/14/01/25/original/zy3y5e3e.jpg[/img]
#Post#: 32910--------------------------------------------------
Re: Piston Failure Analysis
By: jmester Date: January 27, 2014, 7:21 pm
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I would say ate some thing for sure. Would be looking on the
flywheel side for what happen. I would lean toward a piece of
the cage has came out.
#Post#: 32917--------------------------------------------------
Re: Piston Failure Analysis
By: Chainsawrepair Date: January 27, 2014, 8:06 pm
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[quote author=jmester link=topic=1377.msg32910#msg32910
date=1390872097]
I would lean toward a piece of the cage has came out.
[/quote]
Thats what I was thinking.
#Post#: 32921--------------------------------------------------
Re: Piston Failure Analysis
By: jmester Date: January 27, 2014, 9:33 pm
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I say the flywheel side for the deep score by the ring lands on
the flywheel side. Looks like it came up the lower transfer. But
you are probably already ahead of me.
#Post#: 32923--------------------------------------------------
Re: Piston Failure Analysis
By: aclarke Date: January 27, 2014, 10:45 pm
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Bearings aren't smooth because of the crap they were fed.
Intake port shape is clearly evident in the damage profile on
the piston. Foreign object damage wouldn't be to concise
#Post#: 32930--------------------------------------------------
Re: Piston Failure Analysis
By: KilliansRedLeo Date: January 28, 2014, 9:01 am
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Had a Jred 2171 that came in here a while back with almost
identical damage but on the clutch side. Bearings rough also.
Turned out that the ball retainer in the clutch side main
failed. (Metal retainer not plastic) Got caught (I think)
between the skirt and the jug on the up stroke more than once.
Most of it was still in the crank well. Also scored up the
bottom of the crank well.
#Post#: 32931--------------------------------------------------
Re: Piston Failure Analysis
By: 660magnum Date: January 28, 2014, 9:21 am
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My experience with the ball bearings is that the cage is the
first thing to wear out. It is best to change the bearings
before roughness or looseness failure because the damage the
metal of the cage does. Even the plastic cages actually mess up
the edges of the rings. So if you have a plastic Polymide cage
failure, you should also replace the rings as you will find the
edges to no longer be sharp.
Any high time engine should have the case split and the bearings
and seals replaced even if you are just slipping ring(s) in it.
The higher rpm the engine is run, the faster the cage wears.
#Post#: 32937--------------------------------------------------
Re: Piston Failure Analysis
By: KilliansRedLeo Date: January 28, 2014, 10:11 am
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Agreed, 660!
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