Dropped a cylinder

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DartIan

DartIan

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Hello,
So I came home from work the other day and when I turned the car off it clunked hard and backfired out the dual carbs. And smoked out the hood. Now she runs awful and #6 isn't firing. It is getting spark and the spark plugs firing but no fire. Now this has happened a couple times where it clunked stopped but this time it was worse and the cylinder no longer works. I'm thinking valve got stuck and bang but I don't know **** from Sunday I'm still a newb I'm still learning.

1974 dodge dart with a 75 slant from the factory. She was a late bloomer. Has the offy dual carb on it. Nothing crazy other than that. It was advanced 4 degrees cause the offy instruction told the installer to.
 
I guess the easiest thing would be a compression test. It won't fire with out compression.
 
75 will have the peanut head. EZ enough to pull a plug, and put your thumb on the hole and feel for compression bumping a coilless motor. BAd valve will bleed off compression.
 
Like pishta said, and don't be scared about taking the valve cover off, take a look at the rockers and spin the push rods and see if you have one bent or broken. You may even have a stuck lifter if you find a bent or broken push rod.
Look for a hole in a rocker that could have let the push rode come threw also.
 
Tell us more how you determined #6 isn't firing, but is getting spark. I suggest not trying to use slang, especially since you admit being a newbie. I almost passed over your post because the title "dropped a cylinder" sounds strange, like maybe a cylinder liner slipped.
 
I ran the motor and started pulling plugs to see which cylinders weren't firing and #6 was the one causing it to rough idle. I then pulled the #6 plug wire put a spark plug on it an it was sparking. Pulled the #6 plug and it look fine no abnormal coloring. The only noise I heard was the occasional ticking of lifters I don't know if that a bad thing cause I just adjusted them to spec using slantsixdans guide on slantsix.org. Nothing looked weird when I did it and it clunked stop sometime before that too. I didn't strip the rocker I don't believe when I did it. I went over the assembly a couple times. I'm going to pull the valve cover tomorrow to see if there's anything visibly broken. When it runs it runs rough and I have driven the car on 3 cylinders for a couple weeks due to a bad ICM and it didn't sound like this.
 
A bad valve guide seal shouldn't cause it to not fire in the cylinder. It is for oil control only.
I would have another look, maybe there is something mechanically that caused the seal to fail like a stuck valve and the rocker smacked the top of the valve and seal destroying it.
 
Im with dartnut. A seal wont cause a misfire. I would pull the plugs and inspect...
 
The valve guide seal is the only issue. It doesn't hold compression. It is sparking like I said I tested it and the plug looked fine.
 
valve guide seal has no effect on compression
but I bet it can point you in the right direction
 
You said you checked number six with another spark plug and then pulled number six plug and it looked fine.. Just because it looked fine doesn't mean its firing.. Check the plug in the engine at number six and make sure its firing...
 
So i pulled the plug and put it on another car and it worked like a charm. but if its firing and the valve guide seal blew apart then what would cause it to not run if the valve guide seal has nothing to do with compression? wouldnt it still fire and run? like i said i ran the motor and pulled the plug and the motor didnt sound any different whatsoever making me think its just not working. and when i pulled the rest of the plug wires it dropped and had a noticable difference. Anyhoo here is the picture of the carnage i found sliding into the rods. do you think a piece wedged itself in and when it ran it held the rod up and smashed a valve? if so would i be able to see the valve mashed up on the spring?
 

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I personally don't think the seal has anything to do with your problem.. Have you checked compression on that cylinder??
 
No I don't have a compression tool I need to buy one and ill report back when I can. I'm just afraid it'll come to me buying a whole new set up.
 
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