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what exactly does a Leakdown test confirm or check for?

Old 04-22-2005, 09:37 PM
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Default what exactly does a Leakdown test confirm or check for?

What issues will it find? Like bent valves, etc?
Old 04-23-2005, 04:13 PM
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It basically checks cylinder pressure, if you are making good pressure and whether or not it is compressing good or it is leaking out. Which in turn troubleshoots bad leaking piston rings, valves not sealing, seating, or possibly opening and closing right. Ive never done one personally but have seen it done by a friend. Good Luck
Old 04-23-2005, 10:05 PM
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somthin i need to do....b/c im burning oil bad at WOT
Old 04-23-2005, 10:08 PM
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just do a cc check first see how far off they are from each other before you do a leakdown You may find one bad one also look at your plugs if you have a bad hole it may show up on your plug, just my two cents.

Or maybee you just need a catch can.
Old 04-23-2005, 11:37 PM
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A leak down test test the cylinders ability to hold a seal.
If it cannot hold a seal, it will have a high % of leakdown on the gauge. The air that is leaking past the culprit causing the poor seal will tell you what the problem is. Be it a valve, cylinder head gasket rings, etc.
Old 04-24-2005, 08:39 AM
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yes but why start with a leakdown? first I look at the plugs then commpression.
Old 04-24-2005, 08:52 AM
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Originally Posted by SStheBest
somthin i need to do....b/c im burning oil bad at WOT
Have you ever heard/felt detotnation during acceleration? You could have damaged your rings like I did. I would leave a huge cloud of swirling smoke when I went WOT.

Agostino Racing Engines, being a great shop, fixed it 100% free of charge under warranty and rebuilt my entire motor. THANKS AGAIN...ARE!

But, when they did a leakdown check on all 8 cylinders were leaking down between 35-50% The rings were SHOT!

When I would start my engine and take the oil cap off I could feel air blowing out of it like a 200mph leafblower.

I burned a quart every 300-400 miles.
Old 04-24-2005, 08:53 AM
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Originally Posted by SStheBest
somthin i need to do....b/c im burning oil bad at WOT
A leakdown check is easy to do, it takes a matter of minutes to do a couple drivers side cylinders.

Do it man.


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