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Junkyard 5.7 hemi with 22-68% leak down, just rings?

furious70

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I don't have experience with doing leak down tests and guessing what might be wrong.
JY engine with 22-68% , 68 being just one cylinder. More than rings?
Thanks
 
With the leak down tester installed you should be able to hear where the air is leaking from on the cylinder with 68% leakage. Are you looking to purchase this motor or do you own it?
 
Ring butted together, popping piston crown.
Got a bore scope?
They are cheap anymore and a wise investment that has paid for itself
a dozen times over and saved many horrible purchase decisions!

You do not need a high resolution or tech tool.
 
I don't own it and have not seen it in person.
It's a 2017 so was hoping valve seat wouldn't be an issue.
Sounds like I need to ask them to scope it or leave it be.
 
58% is probably a valve issue, whether bent/burned or just not fully closed... Could be as minor as a bit of carbon was knocked loose when removing the plugs and lodged itself between a valve and valve seat... (probably not)

The other seven cylinders put a teaspoon of oil in each one, spin the motor over & retake the test...

If the engine is cheap enough it's still a good core & if all ya gotta do is repair a valve it might be worth the effort.... Then again I like repairing stuff of I can save some $$$$
 
I don't own it and have not seen it in person.
It's a 2017 so was hoping valve seat wouldn't be an issue.
Sounds like I need to ask them to scope it or leave it be.
You can get your own scope that plugs into your phone, under $20 on Amazon.
 
I'm not opposed to one needing some work, I'm boosting it anyway so an excuse to go in and change the ring gap helps.
Will be installing a 392 Cam as well. I suppose a new valve isn't bad, if that's it
 
All used engines are cores to me. This just forces you to freshen it up and it's a bargaining tool to buy it cheaper. 2017 is MDS.
 
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