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compression test results

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Old 09-26-2007, 02:49 PM
  #1  
Cornbread01
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Default compression test results

I did the compression test after finding two of my plugs have carbon deposits.
can any give me any input on the results
well i did a compresion test and this is my findings
on cylinders 2 and 6 there were carbon deposits

dry test
1 175 5 165
2 175 6 170
3 170 7 165
4 170 8 165

wet test

1 175 5 165
2 175 6 165
3 170 7 165
4 170 8 165

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Old 09-26-2007, 03:42 PM
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MrChubs1
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Default RE: compression test results

I'd say everything looks fine. In fact, if you did the tests correctly, your chambers are sealing perfectly (valves and rings). This is actuallynot possible and I've never seen perfect numbers from dry to wet, but that's what you're reporting.

Normally the wet numbers will be a little higher across the board.

How did you do the wet test? Maybe you didn't get enough oil in there. Also, was this done hot or cold? Hot is best, but cold is more common since it's a little easier.
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Old 09-26-2007, 05:56 PM
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97targa
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Default RE: compression test results

I don't like compression tests. I like Leak down test better! They are more accurate
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Old 09-26-2007, 06:34 PM
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Cornbread01
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Default RE: compression test results

i did all the test after getting engine to running temp.... pulled all plugs.. the did dry test starting at 1 going threw 8 wet test i added about a table spoon of oil then tested #1 then added oil to #2 then tested and so on
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Old 09-26-2007, 07:33 PM
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99mustanggt
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Default RE: compression test results

It doesnt make sense that cyl. 6 would loss compression during a wet test.I've never heard of that before.
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Old 09-26-2007, 08:53 PM
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racer02GTstang
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Default RE: compression test results

looks like they are fine.. if you have more than 20 difference then you can have a problem...
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Old 09-26-2007, 09:00 PM
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97targa
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Default RE: compression test results

ORIGINAL: 99mustanggt

It doesnt make sense that cyl. 6 would loss compression during a wet test.I've never heard of that before.
Sounds like the dry test was bogus, or it had blowby already up in the rings to begin with!
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Old 09-26-2007, 09:06 PM
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Cornbread01
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Default RE: compression test results

blow by is very posible that one is the one that has a plug that always gets the carbon deposites on it. awaiting my oil catch can to see if the plug do it again... \
ps i know you can make one (catch can) but i just bought one for 20 buck so no biggy
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Old 09-26-2007, 09:14 PM
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97targa
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Default RE: compression test results

ORIGINAL: Cornbread01

blow by is very posible that one is the one that has a plug that always gets the carbon deposites on it. awaiting my oil catch can to see if the plug do it again... \
ps i know you can make one (catch can) but i just bought one for 20 buck so no biggy
This is why I would do a leakdown test! pull off your oil fill cap and put your lips to it and compare to other cylinders. A good cylinder you will feel a very slight breeze. A not so good cylinder you will feel like someone blowing on you, plus the air will make tons of noise in the line. I bought my leak down test kit at HarborFreight.com It was $29
ps i checked out your gallery photos and the first thing I seen in the thumbnail section is that crease in your rear 1/4panel. that would drive me nutz.
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Old 09-26-2007, 09:44 PM
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Cornbread01
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Default RE: compression test results

yea some lil kid where i live bumped it with his bike drove me crazy i hate it..... urrrrrrggggg
but what can you do...
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