What caused this?

 

Lots of possibilities but first we need to know is this was from an all stock engine or something modified and if it's from a motor with lots of miles on it or something freshly rebuilt.

 

20k on a stock rebuilt 460, this is also the cylinder that the injector was stuck open on...

 

Strange.. obviously the pushrod got displaced from the rocker or the lifter but it'll be hard to tell what happened first. Is the lifter OK? Check the amount of lift from that one as a test for a wiped cam lobe.

 

Best I could tell is the injector wiped out the seal or guide on the intake valve and some how caused the exhaust valve to bend...which in turn put to much pressure on the lifter...the lifter on the exhaust valve wiped out the cam...strange part is this is the push rod for the intake valve... So am swapping out the cam and head from my old motor with the bad ring and dumping this thing!

 

Pretty good indicator on what went wrong, but where is the rest of the story? Bent valves? Stuck injectors? Must have missed something.

Anyways, it's pretty interesting that a stuck injector and a bent pushrod show up on the same cylinder. You say this is the intake valve pushrod? Maybe the stuck injector washed down the valve stem and it stuck, bending the pushrod? No idea how any of this would relate to a bent exhaust valve.

Sounds like you have a spare motor. If you are confidant that the heads and cam are serviceable, swapping them over would be the right thing to do, although freshening the valve job and using new lifters would be advisable.

 

Its all a good guess, I first found out I had a leaking injector...so we swapped out the injectors, after that the first guy that hacked the motor swap bent the fuel rail, broke my dist., starter, tps, and a slew of other parts...so I have been swapping out and fixing everything... I had a vac gauge and it was pulling 19.5 to 20.5, noticed the fuel line in the front part of the rail had a kink in it and the stud on the drivers side front was broken. So I started to swap out the intakes between the two motors when I noticed the bent push rod, after I replaced the push rod I cranked the motor over and noticed the exhaust valve wasn't moving so I pulled that rocker arm rod and lifter, the rod was fine (strangely) the lifter was cupped and had a hole in the bottom...so (was hoping, but turns out not) that the lifter was bad and the cam was fine.


The intake valve looks gummy compared to the rest of them.


1.) Why would the intake push rod be bent?
2.) Why would the exhaust valve bend, misfire, hydrolock?

 

side note no clapping cracking or slappin noises ever came from the motor

 

If you have lifter issues, they could be pumping up and you loose your lash and push/hold the valve open when it shouldn't be. Thus the piston tries to close it and bend the pushrod.

Just a scenario after reading about your failed lifter issue. If one is bad, you could have others with issues. Thus the scenario above.

If the guides are tight that usually won't bend a pushrod. It will bend the valve because the lifter/cam is rotated down where it should be and not cause a problem with the pushrod.

 

if the valve gets bent would that not bent the push rod before causing lifter failure and cam where?


plus with that kind of vac. readings I would assume the compression is good...I don't know I am not a full time or part time tech for that matter...

 

All depends on the orientation of how things broke.

The valve would have to be stuck so that as the camshaft was rotating and trying to lift the pushrod it would then bend the pushrod trying to move the stuck valve. Once the pushrod was out of the way, the lifter would not have any reason to wear out. With the lifter being trashed it sounds like it failed in some manner first.

I would assume the valve would still be stuck right now if it through the pushrod out. Is it? You should be able to tap on the tips with a hammer and get each to snap open. If it goes "thunk", then you have a stuck one.

 

I've had that happen on a Chevy 350 I had a while back. It was hydraulic lock according to the shop. I wouldn't think it would matter what the brand is.

 

Here is my bestest guess, (after pouring over what seems like thousands of posts), the intake valve gummed up and/or wiped out my seal, the leaking injector kept dumping gas into the cylinder and started to hydrolock, once the gas got into the oil a chain reaction started, the lifters started to fail this cause the one to loose pressure and the hydrolock put to much pressure on the other lifter which may have had something stuck to it or the pressure was just to much and caused lifter to fail

 

Well, that's a pretty long reach given the evidence in hand. Hydrolocking will cause some pretty severe symptoms, like bent connecting rods It is also nearly inconceivable that you could fill a cylinder on a running engine with fuel from a stuck or leaking fuel injector, but stranger things may happen?

Sounds like you have recently installed a replacement engine that already had 20K mileage on it. Questionable work from the engine installer did not help, but I think the engine supplier did not give you an accurate description of the condition of the engine. Let's face it, low mileage is a pretty easy claim to make and condition of a used engine can be very hard to judge. Might be worthwhile to talk to the engine supplier if there was any warranty on the engine you obtained. Not saying that there is any reason to expect warranty on used parts, but if it was from a reputable business, they may have a policy in place. If it was from a private seller, they are exempt from any warranty responsibility unless you have it in writing.

 

+1 sounds like that lifter ran dry, no oil flow to the upper valve train, the lifter worn down until it had a hole in it, the rocker arm freezing on its pivot next time around the lifter came up bent the rod.

By the time got the cover off things had cooled allowing things to move freely again.

Someone asked early on to see pictures of everything involved, lacking more to go on no one could say for sure.

We need to know things like where the rod was found, proper position, condition of the rocker arm condition of its pivot point. How much fuel in the oil, any other damage beyond that one rod/lifter.

Fairly safe to say the piston had nothing to do with it, it would hit the valve on to much of an offset to drive the valve up pretzel that rod.

Excessive fuel would be cycled through as long as the valves opened and closed a little bit, goes to fuel in oil, if enough fuel to hydro lock that cylinder? the oil would be loaded with fuel.....that and the connecting rod for that piston would resemble that push rod!

Anyway using information provided, complete lack of lubrication to that lifter is what I believe did it in.