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checking piston rings

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If I wanted to check the piston rings on an engine that is outside the car in the garage, what is the easiest way to do this without a "complete teardown"? I mean I want to know and see if one or more rings are broken. Can I just take off the heads and then remove the pin in the piston and pop them out that way?

 

Rich :)

A leak down test will test the cylinder's ability to hold pressure, not only is this useful for checking rings, but also valve guides and seals.

  • Author

Yeh, but do I have to take it to someone for that? Who would do that?

 

Rich

if you have an air compressor you can do a leak down test yourself with the right adapter. if you hook up a starter/trans to the motor and make sure it has oil you can probably attempt to test compression if you know what you're doing. just give the starter power to turn the motor over enough for a compression test. prop the throttle plate open. i wouldn't do that unless you're comfortable doing it of course.

 

yes you can remove the pistons like you say, after you pull the heads. take note of orientation and location of each piston before removal.

 

if you rotate the engine by hand, you can individually inspect each cylinder wall as the piston goes up and down. look for scuff marks and the condition of the cross hatching. any compromising of the cylinder wall will point to some piston and/or ring problems that you would definitely want to address.

A leak down test will test the cylinder's ability to hold pressure, not only is this useful for checking rings, but also valve guides and seals.
Piston rings and valves = yes, Valve guides and seals = no
  • Author

Think I will have to lean on the idea of taking off the heads and looking for abnormal scoring on the walls. Cannot hook up a starter to it, and that is a good idea!

 

Thanks!

 

Rich ')

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