No compression in two cylinders

JOE WARF

MEMBER
2006 DODGE CHARGER
5.7L
V8
2WD
AUTOMATIC
120,000 MILES

Rebuilt the motor, new pistons, rings, bearings, had the cam checked and heads checked. I switched out the mds lifters for regular ones, removed the solenoids under the intake replace them with plugs. Fired up the motor and it ran really rough, had lots of white smoke coming out the exhaust. I ran it thinking it would clear up but it did not. Would not even idle. I did a compression check and six were good and two had no compression, front two cylinders on passenger side I believe numbers 2 and 4. So I removed the head and everything looked fine. The intake ports for those two cylinders the plastic seems to have melted, ports are not smooth like the rest.
Hoping someone can tell me what caused this and what I need to do to fix this.

3 Replies

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

They melted from heat, but the question is from where did the heat come from?

Did you air up the cylinders before removing the head to see where the compression is leaking?

Roy

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Thursday, May 9th, 2019 AT 3:43 AM

JOE WARF

MEMBER
2 POSTS

Thanks for responding. Answer to your question, no I didn't, wish I had. Been thinking maybe and intake valve was sticking open, that would cause it you think but having two intakes right next to one another doesn't seem likely. I checked the valves and to the naked eye they seem okay. Springs also look fine. Checked head for warpage and they were fine. Checked block and it too looked fine, used straight edge on both. Head gasket had no signs of being blown, don't know if that could be the problem anyways, think I would have just gotten low compression instead of none at all. Same thing if head had a crack in it. Want to think the mds removal could have caused this somehow but don't see how it could. So I thinking it has to be the valve, both intakes. I'm really guessing at this point. Sure hope to get an answer.