problems with my engine HELP!!!

[buff531]

Hey guys,
i have been having some troubles with my engine in the past. To give everyone a brief update as to what happened read below.

i was driving when all of a sudden i heard a very minor tinking noice (sounded like a very minor exhaust leak) then all of a sudden it became extremely loud!! when i stepped on the gas to get over to the side, it was like i had no back pressure and had to give it alot of gas just to move the dam car! anyway my car ended up dieing and would not start the next day. i charged the battery and tried cranking it. The engine wanted to crank but the starter wasnt doing anything, ( you heard it turn on when you tried to start the car but nothing happened). so i took the serpintine belt off along with the spark plugs. the rearmost spark plug on the drivers side was completely bashed up. i turned the engine by hand. It turned counter clockwise just fine, however when i tried turning it clockwise... it would turn then just stop and not move.

so i proceeded to pull the drivers side head and finished this task last night and this is what i saw...

in the rearmost cylinder on the drivers side (same cylinder with the bashed plug) there was a piece of metal about 1" wide and 1/4" thick that was in there. the top of the piston had millions of "lil divits" from the metal bouncing around in there. they valves on the heads were rusted. (is this from the spark plug being completely demolished and not using this cylinder with a spark?)

i dont see anything wrong with the top end of the engine. and cannot locate where that metal piece came from... i am attempting to attach pics with this post lets hope it works...

so where do i go from here? do i need a complete rebuild? how much does something like this cost? would it be wise to bore it out to a 331 and just build the engine up now? how much would this cost roughly???

thanks in advance.

 

[buff531]

heres a couple of pics of the piston....i know they are small but i took them with a camera on a phone....

 

[rd]

Sounds like the timing chain jumped a tooth or two.

Or a valve galled to a valve guide and the piston hit it, or a valvespring died, and let the piston hit the valve. Been there, done that, still have the marks in the piston, two head swaps later......

If the plug broke first, pieces of it could beat up the piston.

Probably need to take some more of it apart, and look over everything from the valvetrain down.

 

[buff531]

Well i looked at the valves on the heads, and i really didnt see any marks. They just looked rusted..

Where should i go from here? i have the engine out of the car. i removed all accessories, upper and lower intake, valve covers, push rods, and the drivers side head... what should the next step i take be?

can i leave the piston the way it is and fix it or does this need to be completely machined?

 

[just4bob50]

you can still use that piston as long as all damage has been contained to the top of the piston, meaning that debri didnt work its way between the side of the piston above the ring and the cylinder wall. if the cylinder wall is not scored you sholud use a dremel tool with a small fine grit stone to knock down any high spots to below the plane hieght that the piston was originaly. we had to do it to my brothers low 11 sec. gt after he missed a shift and the engine over reved. he had the car for almost 2 more years before he sold it and never had anymore problems with the short block.

 

[buff531]

ok ill turn the engine by hand to see if the cylinder walls are scoured...

if they are does that mean i need to get the block machined?

im still trying to figure out what caused the metal piece to get into the engine... and why it wouldnt start.. can you guys help me dianose this portion of it?

 

[buff531]

back to the top...

anyone have any clues where i should look for where this metal piece came from?

im going to try to crank the engine by hand when i get home to see if it completely turns...

 

[buff531]

Update

when the engine was still in the car i tried cranking the engine by hand and it wouldnt turn all the way clockwise... after pulling the heads and finding the piece of metal in there... the engine turns fine.

i checked for scoring in the cylinder walls and it was VERY VERY VERY minimal... i really couldnt feel much i think if i took some like 1200 grit sand paper i can get the scores out...

you thin kthat metal piece prevented my engine from cranking?

why were the valves on that damaged cylinder rusted??? is there anything inside the head that could break loose?

looking from some assistance here guys

 

[StockLX]

well, it can only get in there one way. through the intake tract. trace back up the intake to the throttle body... make sure there is nothing missing or broken. was the engine just recently assembled, or has the heads been off recently? (just wondering if something fell down and got lodged into the intake while having service done, and just recently came loose and went the rest of the way into the engine. jeesh, would be awful hard for it to make it past that valve without causing major damage. are the seats scored up on that valve?

 

[buff531]

what exactly do you mean by the seats of the valves??? as in where the valve sits when its compltely closed? ill have to get a valve spring puller and check that out...


however i had a theroy.. im going to check my throttle body.. since i dont have a blow off valve on my blower, maybe i was at full boost and let off the throttle really fast (like i missed a shift) and it could of broke something loose... ill let you know what i find out going to go look at it on my lunch!!!

 

[buff531]

both plates on my throttle body are still in tact... where else could i look... do you think the metal piece could of came from the blower? everything looks fine from what i can see inside the blower though.

 

[StockLX]

hmm.... Id doubt it could be anything from inside the blower, but i wouldnt rule it out unless you have had the blower apart and checked it out.
do you have an egr valve on your car? is that completly intact?

 

[buff531]

ive been out of the stang sceen a lil while... what exactly is the EGR valve again and where is it located?

also could i use my stock damaged piston if it doesnt have any damage done to the side of it?

How do you "hone" your cylinder walls?

 

[Zero_chance]

Easiest way to hone would be to get a hone from a parts store that you can mount on a drill. Probably wouldnt be that great of an idea to do it with the engine in the car. Youd need to have the piston out and if you didnt have the oil pan off, a lot of crap would collect there

 

[chobracobra]

my old lawn tractor did that once. The screws that hold the throttle plate to the throttle shaft flew off somehow, and proceed its way down the carb and into the compustion chamber. noisy scary sounds followed, and when i took off the head, the piston was thrashed up and the head was pretty bad too. The cylinder wall was ok so i just grinded down what i could on the head and piston and have been using the engine for 4 years now. i would check all screws and fittings inside the engine, and if everything is there, it may have a been a foregin object somehow someway. what do you mean when you say the valves are rusted??

 

[buff531]

with that metal piece bouncing around it compltely demolished my spark plug... i guess the plug wasnt even firing... since nothing was being ignited... eventually the valves on the cylinder head started to rust.....

 

[Zero_chance]

Yeah but chances are the metal wasnt in there the entire time or you would have noticed it long befoire it started to rust. You sure it isnt carbon?

 

[chobracobra]

so your sayin, after the inncident you pulled the spark plug and ran it on 7 cylinders? or you just let it sit with the spark plug out?
EDIT://nevermind...stupid question i read it some more

 

[buff531]

OK guys... i got another update.

i pulled the pistons last night. the one that was damaged would not rotate at the pivot point... i couldnt even force it... what does this mean? would this help us figure out where the metal chunk came from. Both piston rings were in tact on the piston so that is out of the question as to if the piston ring was the metal piece.....


to answer the other questions... im not to sure if its carbon. i dont know what carbon looks like. thats why i posted pics.. i always figured carbon was a black residue... hoever this was a silverish material that was hard like a rock ( i think it even had a couple of gold spots in there, maybe from rubbing on something or glazing from all the heat)

i left the spark plug in the hole. i didnt know it was bashed up until my engine died and i pulled the plugs to find out what cylinder was wrong...

 

[bluevenom867]

i pulled the pistons last night. the one that was damaged would not rotate at the pivot point... i couldnt even force it... what does this mean? would this help us figure out where the metal chunk came from. Both piston rings were in tact on the piston so that is out of the question as to if the piston ring was the metal piece.....

You mean the wrist pin?

Sounds like the same thing that happens on a motor that goes through sever detonation.