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Will I need a new engine? Compression test results

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Old 09-12-2011, 07:07 AM
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dsmZ
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Default Will I need a new engine? Compression test results

I've been burning oil (5quarts/~600 miles~) so I decided to finally do a compression test... after pulling the coils, there was no oil in the tube, but some oil on the lower threads of the plugs (meaning from inside the cylinders). With the amount of oil being burned, you would think there'd be a smoke screen behind me, but I honestly don't see that much--if any...

Two of the plugs looked pretty fouled -- they were changed in maybe February of this year, giving me a random misfire and all four O2 sensor codes

Dry results were
235|190
210|185
210|185
front

Wet results
240|235
250|235
250|220
Front

My warranty ended two months ago.. how much am I screwed?
Old 09-12-2011, 08:05 AM
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Italianjoe1
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Miles on the engine?

Did you always go in the same order?
Old 09-12-2011, 08:12 AM
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0jiggy0
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Wow your burning 5 quarts in 600 miles? Numbers worse then that. Maybe your dsm infected your z. J/k

Those numbers don't sound terribly low to be. See what a leakdown turns up.
Old 09-12-2011, 10:51 AM
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dsmZ
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Haha leave my dsm alone! :-)

Its about 80100 miles on the engine-- and yes, same order. I tested each cylinder 2x to confirm I got the same readings...

I'm assuming the leak down would show if its the valve seals vs the rings?
Old 09-12-2011, 11:07 AM
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dsmZ
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Sidenote: it makes me think it may be the seals because if I leave the car for 2+ days and start it, it bogs down and smokes like crazy, until all the oil burns out the cylinders ... sound about right?
Old 09-12-2011, 11:10 AM
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mike_eee
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sorry being a noob here, how come the op burn 5 quarts in 600 miles...i thought we had only 5 quarts of oil in the sump...unless u have a spacer + oil cooler that's 2 plus extra quarts...or was it a typo...0.5 quarts in 600 miles


Mike
Old 09-12-2011, 11:24 AM
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Italianjoe1
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Oil loading the cyls after sitting sounds exactly like valve seals.

Any chance you over-revved the engine at some point? Long periods between oil changes? Could be valve guide problems.
Old 09-12-2011, 11:44 AM
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dsmZ
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When I say 5qts, I mean enough where its almost nothing on the dipstick, and if I make a sharp turn, the oil light will flash.

Don't believe I've over revved before... I can maybe think of one or two times since I've had the car (2007)... nothing recently. And I've changed the oil every 3-3500 even when I started using synthetic a few yrs back--
Old 09-12-2011, 12:44 PM
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350zion
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Originally Posted by dsmZ
When I say 5qts, I mean enough where its almost nothing on the dipstick, and if I make a sharp turn, the oil light will flash.

Don't believe I've over revved before... I can maybe think of one or two times since I've had the car (2007)... nothing recently. And I've changed the oil every 3-3500 even when I started using synthetic a few yrs back--
Those numbers look pretty good to me, but I'm confused. u say u burn 5 qts. Every 600 miles but u change the oil every 3500 miles... Were u referring to before this problem ?

As others have stated perform a leak down test...
Good luck!
Old 09-12-2011, 12:47 PM
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graffkid732
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What year is your car? Is it Rev up or regular DE?
Old 09-12-2011, 01:28 PM
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dsmZ
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Originally Posted by 350zion
Those numbers look pretty good to me, but I'm confused. u say u burn 5 qts. Every 600 miles but u change the oil every 3500 miles... Were u referring to before this problem ?

As others have stated perform a leak down test...
Good luck!
I used to change it every 3500 miles (since I was asked if I was late on oil changes), but now I just fill it up/top it off every 600 or so... when my "oil & filter reminder" comes on, at 3500, I still do the routine oil change & filter


Its a 2004 roadster DE
Old 09-12-2011, 01:49 PM
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djamps
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2004's aren't known for oil burning. The 'big' problem started with revups.
Old 09-12-2011, 02:10 PM
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Jeff92se
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Originally Posted by Italianjoe1
Oil loading the cyls after sitting sounds exactly like valve seals.

Any chance you over-revved the engine at some point? Long periods between oil changes? Could be valve guide problems.
If the compression looks good, I'd also suspect the valve seals.
Old 09-12-2011, 03:03 PM
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dsmZ
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Is there a write-up on how to do this (including torque specs) anywhere on here/online?

Also, any other parts I should think about replacing while I have everything apart? Gaskets, timing components, etc...

Thanks for your help so far guys!
Old 09-12-2011, 03:28 PM
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DaveJackson
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Originally Posted by dsmZ
Is there a write-up on how to do this (including torque specs) anywhere on here/online?
I was planning on making one of these "when I get around to it" and I've glanced at this link: http://www.650motorcycles.com/LeakDownTester.html
But, I have not looked far enough into it to see how viable it is. I think a leak-down tester is something like $100, so if this is reasonably easy:
Old 09-12-2011, 03:33 PM
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dsmZ
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Originally Posted by DaveJackson
I was planning on making one of these "when I get around to it" and I've glanced at this link: http://www.650motorcycles.com/LeakDownTester.html
But, I have not looked far enough into it to see how viable it is. I think a leak-down tester is something like $100, so if this is reasonably easy:
I was actually referring to a writeup on doing the actual valve seals, not making a tester, BUT I def. saved that link to my favs for future distribution-- thanks!
Old 10-08-2011, 06:31 PM
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Those compression readings are too far apart from each other.
IIRC rule of thumb is "20Psi range between cylinders is max"

Leak down will tell you where the problem lies.

Wouldn't be suprised that at this point the engine is leaking compression in several locations.
Old 10-08-2011, 09:25 PM
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winchman
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I don't understand why oil would leak past the valve stem seals when the engine is off. There's a good supply of oil to the cam and lifter area while the engine is running, but that oil should quickly drain away from the stem seals as soon as the engine stops.

Was there a significant difference in engine temperature between the time you did the left and right banks? I'm having a hard time coming up with an explanation for all three cylinders on one side being so much lower than the other side.
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