High compression in one cylinder, smoke in exhaust

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jusroln
Posts: 4
Joined: Tue Sep 18, 2018 8:20 pm
Car: 2007 G35x

High compression in one cylinder, smoke in exhaust

Postby jusroln » Tue Oct 09, 2018 7:26 pm

So, my engine threw a rod and bit the dust. I replaced it with a used engine that sounds good but is blowing smoke. I get a big puff at start up and a lot of smoke when accelerating. I dropped the exhaust and determied it was coming form the drivers side. I think the head gasket is good (no oil/coolant mixing, block test didn't show any exhaust gases,...). Did a compression test. All cylinders are around 160psi on my gauge but cylinder 6 is at 185 psi. Tested each cylinder 3 times. Cylinder 6 builds to 185 and then it leaks down rather quickly. When I pulled the tester out it had oil all over it and around it. So, does this sound like valve seals or valve stuck open or does it sound more like a ring issue. Just need to decide if I'm pulling the motor and returning it or if I could get by with replacing some valve seals.


jusroln
Posts: 4
Joined: Tue Sep 18, 2018 8:20 pm
Car: 2007 G35x

Re: High compression in one cylinder, smoke in exhaust

Postby jusroln » Tue Oct 09, 2018 8:34 pm

Forget to give vehicle info. 2007 G35X auto.

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telcoman
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Re: High compression in one cylinder, smoke in exhaust

Postby telcoman » Wed Oct 10, 2018 2:41 am

Return it

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audtatious
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Re: High compression in one cylinder, smoke in exhaust

Postby audtatious » Fri Oct 19, 2018 12:01 pm

Honestly it can probably be either. You can try using a scope to inspect the piston and any scoring or issues going on. Otherwise you would have to pull the head for further investigation. If the ring/piston is fine then a head job should fix it up.


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