Compression ?s
09-19-2007, 11:49 PM
#1
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Compression ?s
The story; When my car is at WOT it pushes oil thru the dip stick and the valve cover breather (no,I did not over fill it with oil). I bought a new pcv valve, still the same problem. So by then I'm scaried its theengine so I checked thecompression. All cylinders checked in at 175-185 except for cylinder 1 & 8, they checked in at 165. My friend say it was fine but I want a second opinion, and if it is fine then what else can it be?[&o]
09-20-2007, 12:05 AM
#3
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RE: Compression ?s
ORIGINAL: r.barn
You need to do a leak down test.
Where you pump compressed air in and measure the percentage drop.
Thats a real test to see whats giving you your blow-by and excessive crank case press.
You need to do a leak down test.
Where you pump compressed air in and measure the percentage drop.
Thats a real test to see whats giving you your blow-by and excessive crank case press.
09-20-2007, 12:18 AM
#4
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RE: Compression ?s
I found this definition on the web: You are losing pressure in to the engine
and causing excessive crank case pressure, so you need a leak down test
While a compression test is a dynamic test (engine moving), a cylinder leakdown test (C.L.T.) is a static test (engine at rest). The compression test measures how much pressure the engine can produce while cranking; in contrast to the C.L.T., which measures how much pressure is lost in the engine internally.
and causing excessive crank case pressure, so you need a leak down test
While a compression test is a dynamic test (engine moving), a cylinder leakdown test (C.L.T.) is a static test (engine at rest). The compression test measures how much pressure the engine can produce while cranking; in contrast to the C.L.T., which measures how much pressure is lost in the engine internally.
09-20-2007, 02:02 AM
#5
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RE: Compression ?s
ORIGINAL: r.barn
I found this definition on the web: You are losing pressure in to the engine
and causing excessive crank case pressure, so you need a leak down test
While a compression test is a dynamic test (engine moving), a cylinder leakdown test (C.L.T.) is a static test (engine at rest). The compression test measures how much pressure the engine can produce while cranking; in contrast to the C.L.T., which measures how much pressure is lost in the engine internally.
I found this definition on the web: You are losing pressure in to the engine
and causing excessive crank case pressure, so you need a leak down test
While a compression test is a dynamic test (engine moving), a cylinder leakdown test (C.L.T.) is a static test (engine at rest). The compression test measures how much pressure the engine can produce while cranking; in contrast to the C.L.T., which measures how much pressure is lost in the engine internally.
09-20-2007, 09:29 AM
#6
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RE: Compression ?s
You probably need to delete the pcv system and install 2 breathers. On supercharged aplications the stock pcv system isn't going to all blow by gases to escape fast enough.
Definitly do a leak down test, your rings maybe still letting to much blow by through.
Definitly do a leak down test, your rings maybe still letting to much blow by through.
10-02-2007, 10:56 PM
#7
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RE: Compression ?s
I think this is the problem. The pic is showing where the pcv valve inserts into the intake manifold. What is inside, is a bunch of wired mesh, im guessing its acting as a filter but does not let it breath enough. Has anyone seen this? Is it ok if I take this out?
10-02-2007, 11:43 PM
#10
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RE: Compression ?s
ORIGINAL: 04gtstang
DAMM!!! Is there any other way around it? That means that a shop have to do that right? Have any other supercharged guys ever experienced this?
DAMM!!! Is there any other way around it? That means that a shop have to do that right? Have any other supercharged guys ever experienced this?
you just block off the PCV crap and run a breather on both valve covers...
