Spark Plug Hits Piston

[allened]

Ok my number two cylinder is smashing in the spark plug really bad. I just did the time and it is set perfect and I dont understand why it is hitting it. And its not a little hit it really is smashing it all the way down.

 

[GSXSixteenG]

Did you just rebuild?.. Was the block and head just decked? What kind of proof do you have?

 

[allened]

The head was redone with metal gaskets and I like i said it was running then BAM i checked to plugs and sure enough it was crushed I replaced it and started it again and crushed that one. Now if you turn the crank by hand it wont go past the number two cylinder. Its like its hitting the head.

 

[stefanOst]

Easy thing to check would be to make sure you have the right model spark plugs in.

 

[jdigitty]

That happened to me not to long ago. First time I was using e3 sparkplugs that are longer then stock the second time it was wrong gab and over torqued got some ngk pluges gaped right and just tight enough to seal started right up.

 

[GSXSixteenG]

The piston would hit the valves before the spark plug, unless something is already broke and floating around on top of your piston. It could be a detonation problem, but there is obviously another problem persisting now. Redo/double check the timing then compression test to rule out bent valves.

 

[boostd_mitsu]

the timing wouldn't matter if the piston was hitting the spark plug, it would smash the valve if were out of time. i would put the right NGKs in there and see what happens.

 

[allened]

The plugs are the right ones and I did recheck the timing and the values arent bent. Im going to scrap it just get rid of it its not worth the trouble for me but thanks for letting me now your thoughts.

 

[68442]

I suspect a weak injector. If you look at bare head you'll see its pretty hard to hit a spark plug.

 

[Rob10_99]

Sounds like a valve got broken or bent. How do you "know" its in time after it spit 2 spark plugs at you with damage?

 

[#40Fan]

$10 says it blew a spark plug at one time and they either heli-coiled it or put an insert in it. Both ways would/could allow the plug to sit too far in the chamber.

One way to test this would be to pull all 4 plugs and rotate the crank by hand and see if it still trys to stop when #2 is on TDC. If it doesn't with the plugs removed, then the plug depth is the problem.

 

[allened]

Even with the plugs out it will stop at the #2 TDC there is no pushing past it there is no broken value on the piston i used a magnet pen to check.

 

[96eclipzGsT]

Just put a washer under the spark plug.

 

[tenn-gsx]

Is this a new or freshly rebuilt engine? If so who did the work? What size is it? 2.0, 2.3 , 2.4?

 

[Dizorganizer]

If the piston has crushed 2 plugs wouldnt there be a problem with the piston now?

 

[GSXSixteenG]

There is no way the piston can come in contact with a spark plug unless other problems were there. Are pistons are dished in on top and the top of the piston camber is like a dome. The piston would hit valves before anything else. Here is an example image I found online.

 

[donniekak]

Broken ringland floating in the cylinder. Peek in there with a flashlight.

 

[DSM1G90]

..or, take a magnetic probe down the bore and see if anything comes attached to the probe. I bet you got a nut or similar that got loose from the intake area and found it's way into that bore - why No.2 can't come up.

 

[DSMopar]

Just take off the flipping head obviously something is way screwed if you have piston to head contact...

 

[soulefood]

good luck with that bro.. hope you find out what it is.

 

[allened]

Instead of taking of the head first i though it would be faster to drop the oil pan and look up. What i found was the #2 piston had come lose from the crankshaft so it would separate on the top of its stroke and hit the head. From there crushing the spark plug and then bending the four values for that piston. the piston is now screwed up so its going to need a whole new engine unless i rebuild this but im thinking is better to buy a new engine or just sell the car.

 

[donniekak]

Wow, you didn't hear it knocking first?

 

[mindset]

you need a valve job. Find a junkyard head, use the valves from them and have someone who knows what their doing install them in the head you have now. Great time to get ARP's and a new headgasket. Just get an OEM one.

If not I'll give you $500 and I'll come pick it up.

 

[falcon8r]

Instead of taking of the head first i though it would be faster to drop the oil pan and look up. What i found was the #2 piston had come lose from the crankshaft so it would separate on the top of its stroke and hit the head. From there crushing the spark plug and then bending the four values for that piston. the piston is now screwed up so its going to need a whole new engine unless i rebuild this but im thinking is better to buy a new engine or just sell the car.

That bites ! I spent some time around Cosworth 4 bangers in the past and had engines come apart on the warm up lap. A sick feeling in the stomache for sure. These were expensive engines built by big name shops, not me. I just installed and maintained them. It happens. Typicle of human flaws and bad juju. Tres....

 

[Kaotic_red]

Wow, you didn't hear it knocking first?

That was my presumption at first as well but he didnt say anything about starting it.

Now for the OP...its always the stupid things that are over looked. If I were you I would be praying/thanking the car gods that you didnt try to start it and end up with a jacked motor. plugs are cheap...now go to the gas station, buy a lotto ticket and win because you my friend are one lucky SOB.