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Discussion Starter #1
My #'s ranged from 170-183 all around. I did this w/ the car warm, but I had to re-warm the engine halfway thru because I was going so slow.

They seem a little low, but at least they're all w/in 10% of each other. My only question is, how long do I need to turn the key to build max psi? I was doing this by myself and couldn't watch the gauge.
 

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The rule of thumb is eight rotations of the crank at a minimum, I believe. Did you hold the throttle open while doing it? if not, this can account for a low reading.

Hope this helps.
 

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You should crank it until the needle won't rise any further. It never takes more than 5 or 6 on my car. My readings are all between 190 and 200. Hot or cold. Hot will usually make them a little closer to one another.

I do mine with all plugs, coils and injectiors disconnected. All plugs removed and WOT while cranking. Because there is only one cylinder with compression you should be able to hear each compression stroke on that cylinder.

Ed
 

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Discussion Starter #5
I stated earlier that I couldn't see the gauge. I was doing this by myself, so I can't see when the needle stops rising. I don't know what each stroke or rotation sounds like.

So how long do 4 strokes take, 1 sec, 2 sec, what? Please give me a length of time so I know how long to turn the key.
 

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Length of time is going to depend on how old the battery is, how much abuse the starter has seen, ect........ It would be easier to get your neighbor to help. Have him/her turn the key until the needle stops rising.
 

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With all of the plugs out crank the car. It will be smooth sounding with sounds from compression at all. When you install the compression gauge only that cylinder will have compression so you'll hear that compression stroke each time it come around. It's pretty easy to hear.

Ed
 

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Discussion Starter #8
Ok, I'll give it another try this weekend.

Does the compression stroke have a distinctive sound to it?
 

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I also did it myself and i just let it crank for about 3 seconds. Just for your reference, my readings are about 190-ish for all 8 cylinders.
 

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Phydeaux said:
Ok, I'll give it another try this weekend.

Does the compression stroke have a distinctive sound to it?
Yes it does.

Because your doing nothing but squishing air you'll hear the crankshaft slow a bit and maybe even a little hissing.

Ed
 
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