Bent valve?

[redmustangt]

I had a rattle in my engine on the passenger side so I took out my passenger side plugs to make sure none of them were loose. I went inside while the plugs were out and my buddy decided to screw with me and turned my car on. I shut the car off pretty quick. I then put it back together and tried to start it, it wouldnt. Then I spun my crank pulley and it will spin both left and right but when it hits a certain point the engine locks up.
Would this be a bent valve or maybe something worse? Any help would be appreciated

 

[stangman11]

What kind of rattle was in your engine when it was running before you took the plugs out can you describe it? Did it sound like valve train or bottom end of the engine. Also turning your car over while the plugs out should not do any damage what so ever mechanically to the engine. Your computer may be confused with all the false values it was receiving with the plugs out. Try leaving the battery dissconnected for around 30sec-1min and reconnect. This should clear your computer values and reset itself and try to start it again.

 

[trinity_gt]

When you took the plugs out were any mechanically damaged? Electrodes folded, gaps closed, porcelain shattered etc?

Sounds like something is loose inside one of the cylinders and it's getting sandwiched between the head and piston at TDC. What else is there to the story? Can you backfill a bit: Does the engine have nitrous or a blower? Custom tune? When did this "rattle" start (e.g. right after a 75-shot at the track...)?

 

[redmustangt]

No the plugs were fine. The noise I was hearing sounded like an exhaust leak from the header. I was hoping that it was a loose plug instead because that would be easier than checking my headers. The car doesnt have nitrous or a blower. It has a mail order tune.
I am certain that nothing fell into the engine. I left the battery unplugged and the car wont start still wont spin in a full 360.
Also when the car was spun over all of the drivers side injectors and plugs were hooked up. The car started on 4 cyl with only the drivers side firing

 

[stangman11]

When its turning over now you said it wont turn the engine over a full 360 degrees? While cranking do you hear any noises comming from the valve train or any odd noises at all from the engine? Binding? Metal to metal contact, a rattle or anything?

 

[redmustangt]

No I dont hear any noises. The starter will spin the engine until it hits the point where it locks and then the starter whines like it is trying to spin but is being held in place

 

[stangman11]

I would have to agree with Trinity GT then it sounds like something is being wedged in the cylinder. At this point to prevent furthur damage to the engine by trying to turn it over I would start to remove the head on the one side and see whats going on. The only other thing I can think of is possibly a binding of the timing chain, which may have been your noise from the get go and when the car was turned over with no plugs in it put a kink in the chain or slightly broke the chain. Its hard to say you wont find out unless you take that head off.

 

[redmustangt]

Ok well Ill start that tonight. I post what I find.

 

[redmustangt]

Well I took the head off and it looks like the intake valve on the piston closest to the fire wall just nicked it. The piston isnt damaged it just had a spot on it where all the carbon has been scraped away. The valve is a little messed up though. My buddy owned up to it and is buying my new valve though. When I took my head off I also found a crack in my header that was making the rattling noise.

 

[fast97gt]

Don't forget to buy new head bolts, also to kick your buddys ace, I would
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[stangman11]

Glad to hear you found the problem but there is no reason that the valve should have hit the piston just because the plugs werent in the head. That motor is an interference motor so the only way it would allow contact from the valves to the head in a jump in timing. I would take a look at your cam timing to make sure its correct and if the chain and tensioner are in good shape. Seeing at that you have the one head off already you might as well do the timing chain and both head gaskets. I mean why not your already in there.

 

[stangman11]

Yea and give your buddy a nice kick to the teeth for being dumb. lol

 

[redmustangt]

stangman11 I think that you are right about the timing being off. When you set the timing the drivers side cam dowel marks are supposed to be at 12 oclock and the passenger side cam is supposed to be at 11 oclock and the passenger side piston closest to the radiator (just making sure) is supposed to be TDC right?
When I took my passenger side head off I left the chain on the driver side head so I could check the timing and when the #1 piston is a TDC the drivers side cam is at 1 oclock which would mean that it did jump timing.
Unless I am wrong. I got my info for setting the timing from http://home.comcast.net/~srchop16/S4B31B32.pdf

 

[trinity_gt]

If the timing is suspected to be off, you might want to pull the camshaft on that head to check the journals for evidence of oil starvation. Pull the timing chains and sprockets and verify that the keyways and keys are in good shape too... Maybe it didn't "jump" but rather a keyway gave when a camshaft seized...