[99v6stang]

Okey so my engine blew up when i was installing a new cam, i was wondering if anyone could tell me what i did wrong by looking at these pictures.
http://www.putfile.com/pic.php?img=6759409
http://www.putfile.com/pic.php?img=6759408
http://www.putfile.com/pic.php?img=6759407
http://www.putfile.com/pic.php?img=6759407

[tomzac]

How long did it run before letting go? Did it run at all? If it ran, what did it sound like? Is the piston the major cause of failure? What does it look like? Adding a cam will increase the engine's air intake. Did you get it retuned? Some clear pics of the piston will probably tell what went on inside the chamber. It might be a nasty case of bad preignition with our hard/brittle pistons. They are not very forgiving to detonation.

[stephen]

Originally Posted by 99v6stang Okey so my engine blew up when i was installing a new cam, i was wondering if anyone could tell me what i did wrong by looking at these pictures. http://www.putfile.com/pic.php?img=6759409 http://www.putfile.com/pic.php?img=6759408 http://www.putfile.com/pic.php?img=6759407 http://www.putfile.com/pic.php?img=6759407

From picture one it looks like a piston came apart. Is that correct? I appear to be looking down a cylinder bore from the top with the rod in place but no piston. It also appears that there is some crankshaft damage near the rod journal. In addition the cylinder head and spark plug on the corresponding cylinder appear to be damaged. Possibly this secondary damage is from debris from the broken piston.

As to the cause. It sure looks like a collision between a valve and piston due to incorrect valve timing or incorrect valve lash.

[Onemanzu]

Originally Posted by stephen From picture one it looks like a piston came apart. Is that correct? I appear to be looking down a cylinder bore from the top with the rod in place but no piston. It also appears that there is some crankshaft damage near the rod journal. In addition the cylinder head and spark plug on the corresponding cylinder appear to be damaged. Possibly this secondary damage is from debris from the broken piston. As to the cause. It sure looks like a collision between a valve and piston due to incorrect valve timing or incorrect valve lash.

well said... from the pictures it looks like there was contact made between internal parts on the engine... which isn't a good thing by any means

[tomzac]

Valve contact is a good guess. I've seen some pretty damaged valves from a incorrectly timed interference engines with little more than valve dings in the top of the pistons. But most of these were engines with forged pistons. It doesn't take much to shatter the stock ones.

[CosmoRide]

If you need a new engine go to lkqonline they have the best deals,
or you could go to rpm-mustangs and get the 4.2 stroker

[02ponypackage]

so much for a "built" motor of yours

[Luvdmustang]

sorry your engine blew up. was this a first time installing a cam?

[itschristorres8]

could be lots of things...
may have been a blown head gasket allowing heat to target that one spot
or a worn rod journal that some how hit your head even then the damage would be worse if that was the case. looks like there was just a weak spot there and the heat target'ed it and lead to that.

hows the block?
maybe a new head and head gasket is all you need

[99v6stang]

Yea, the piston was ripped apart and most of it was shot out the oil pan. At first i thought it was a problem with the timing, but there are no marks from the valves on any piston, and the valves from the cylinder that blew up are in perfect shape as well. The engine blew up right after starting. It started, sounded terrible, shook, then blew up, and all this took place right after installing the cam. The cylinder walls are also still in great condition so i am very confused on how this happened. I was also thinking that maybe same part or tool somehow fell in there, but i dug out everything and felt around with a magnetic stick but retrieved nothing but chunks of piston and rings. I did no get the car retuned, but i dont believe that would cause such a problem. I will be taking ths engine out tommorow to install my 4.2 so i will try to get more pictures then. I just want to know what cause this so it doesnt happen on my new motor.

[Luvdmustang]

this is something i never heard of, let alone actually dealt with. I cant think of anything that would of caused it