Hurt my motor?

[Anonymous]

HEY GUYS,

how bad do you think a 1/4 inch bolt will hurt my engine. i was using a scre and bolt to hold my air cleaner on my carb and well today driving i heard a terrible knock noise. i stop ipen the hood start looking around and notice my aircleaner is loose and the bolt had falling into the car into the motor. i took off the carb to look in the intake its not their so i assume it fell into the block. however it starts no knock now and good power. i am thinking of pulling the plugs and with a flash light taking a peek at my pistons and seeing if their is any lashes or anything. should probly do a compresson test to chekc the cylinders leakage, too. So wat do you guys think happend to that bolt, what could it have done to the poor motor

wes

 

[CoupeBoy]

That terrible noise was the bolt/screw getting beat and pummeled until it either got flattened between the piston and head OR embedded itself into the piston or head on that cylinder. My younger step brother did this to dad's '84 F150 5.8 about 2years ago. They pulled the head and removed the remainder of the bolt and reassembled the motor. Dad ran it that way for about 2 months then he could not stand the pinging noise that came from the motor and pulled. a '76 5.8 now resides in that pickup out of a Grand Torino Elite.

You wont really know the extent of the damage until you pull the head.

-ron

 

[Anonymous]

doesnt seem to be pinging or knocking anymore though, im just worried it will start again

 

[CoupeBoy]

For the price of a headgasket and a few hours you could really find out what happened. Did it damage the intake valve on its way in? Did it damage the exhaust valve while it was getting pummeled? Did it scratch the cylinder wall while it was geting beat up by the piston? Where did the bolt/screw go? Could it get dislodged again and cause the same problem? Will your motor notice if 1 piston weights more then the others?

Seems risky to me NOT to know for sure.

-ron

 

[64.5 TX Stang]

Yeah I have to agree. Pull the head and see what the damage is. I had an Eagle Talon that threw a timing belt and I was amazed at the damage done to the inside of that engine. The forces generated inside the cylinders are tremendous. Even that little screw could do quite a bit of damage.

 

[Junk-Falcon]

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[Anonymous]

Just wondering if the head of a 1/4" bolt can make it through the intake valve. I think valve lift may not be enough. But, the threaded end of the bolt could cause havoc in the valve/seat area.
Doug

 

[AzCoupe]

Speaking from experience, it can do massive damage. You definitely need to pull the head and see whats up. It may be OK now, but if it did in fact drop down into the cylinder, it could eventually sieze the motor. If a small piece gets down in the rings, it will trash the cylinder walls in no time flat. Spend a weekend or two and save your motor. More than likely, you'll need to replace a valve, or two. It may have worked its way back up into the intake runner for the moment, but sooner or later it will find its way back to the valves. Or its in tiny pieces floating around in the cylinder and you just can't hear it now. But if it droped into a cylinder, its still there, doing its best to trash the block.

 

[Titleist16]

I had the tip of a spark plug break of about 9 months ago. It really dinged up the top of my piston. I had to have a new piston put in. I would think that a bolt would really tear upart a piston. You should probably take a look at the piston and probably replace it.

 

[Anonymous]

Well pulled the head and found a cracked valve piston and cylinder walls are ok, the valve cracked from the base to the stem straight down, never seen anything like this in my life. took it to the machine shop they said we are a bunch of idots for installing port devider, but hes the best in and cheapest in town so i have to go to him. while my head is off can you guys think of anything that i can do to maybe add some performance.

wes

 

[Anonymous]

Also compression test failed as well witch is confuseing me because it has 155 on cylinder 1 cylinder 2 has 152 cylinder 3 has 0 cylinder 4 has 40 cylinder 5 has 0 and six has 0 i cant believe my poor motor was even running. the pistons appear to be good i think the rings are good too any better way to test em.

wes