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  #1  
Old 10-14-2010, 03:11 PM
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Compression test without valve adjustment first...

I purchased a cheap compression tester from Harbor freight on Tuesday. I'm really excited to check the health of my engine but haven't received my wrenches to do a valve adjustment first.

Is it a total waste of time to check the compression without doing a valve adjustment first?

digi

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  #2  
Old 10-14-2010, 04:54 PM
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Yes, its a waste

Wait and do the Valves.
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  #3  
Old 10-14-2010, 05:09 PM
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If you have a feeler gage, you can tell if any of your valves are out of adjustment. If they do not need adjustment, there is no reason not to do a compression test.

You may waste the time that it takes to pull the valve cover, affected vacuum hoses and throttle linkages in this process.
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Old 10-14-2010, 08:33 PM
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Quote:
Originally Posted by digieditny View Post
I purchased a cheap compression tester from Harbor freight on Tuesday. I'm really excited to check the health of my engine but haven't received my wrenches to do a valve adjustment first.

Is it a total waste of time to check the compression without doing a valve adjustment first?

digi
Hi
Were it me, I'd run a warm (85C.) compression check just for the fun of trying out my new guage. The valves have to be really off before they will affect compression readings and its not that much work to do over should need be.
Joseph
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Old 10-15-2010, 03:21 AM
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Quote:
Originally Posted by jkubica View Post
Hi
Were it me, I'd run a warm (85C.) compression check just for the fun of trying out my new guage. The valves have to be really off before they will affect compression readings and its not that much work to do over should need be.
Joseph
I agree, but learning is half the fun- I would take a compression test warm (unadjusted) and then a warm adjusted reading-always satisfying to see a low cyclinder pop up 50 or more pounds via valve adjustment
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Old 10-15-2010, 03:46 AM
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Hey,
Why dont you check your oil level after you drain the motor before you add the new oil?
You could check your tire pressures just before they fit new tires.

Maybe check your battery acid SG before you charge it.
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Old 10-15-2010, 09:32 AM
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Hey,
Why dont you wipe before you poop?
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  #8  
Old 10-15-2010, 09:39 AM
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wow, guys, kinda rough with the ribbing...
he's got a new tool.
I LOVE NEW TOOLS! ya gots to play with them when they arrive!
I just got my new spring compressor... I am itching to tear something apart.
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  #9  
Old 10-15-2010, 09:53 AM
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Smile

Quote:
Originally Posted by layback40 View Post
Hey,
Why dont you check your oil level after you drain the motor before you add the new oil?
You could check your tire pressures just before they fit new tires.

Maybe check your battery acid SG before you charge it.
Hi
Well now, I was talking about the joy of learning and trying out a new tool.

However, if you do get good compression numbers before a valve adjustment - and assuming good oil pressure and no noise like rocks in a tin can - you know have a generally sound engine.

If the compression numbers are not so good, then you need to check for valve clearance, faulty valves, stuck or worn piston rings, leaking head gasket & etc.

Not to say of course that valve adjustments and other normal maintainence shouldn't be done as MB recommends.

As to your other suggestions, I do see some value to each one - except I would check the oil level before draining.

The above all in a friendly spirit.
Joseph

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