Engine Is My Cam Broken?

[93silverlx50]

So I've got a crappy running car that I've got a long thread on. I will skip to the question. So could my Cam be cracked in 2?

I pulled off my upper and lower intakes and valve covers. I was adjusting my rockers that were loose and when I hand cranked the motor, I found that the rockers on cylinders 3,4,7 and 8 were not moving. I watched the lifters and saw zero movement there too. I pulled a lifter from #3 and swapped it with #5. That lifter rises and falls in #5 when I hand crank the motor the good one from #5 doesn't move in the #3 cylinder position. I thought my lifters were bad until I swapped them. Then without a lifter in #3, I put a pushrod where it would go and slowly hand rotated the motor. I didn't see any movement or any noise from the pushrod which I think in theory should ride and fall with the cam, is that correct? So could my Cam be snapped? Before I started taking the motor apart, it ran like it was only running on abou

t half it's cylinders.

On a side note, I also found my block has a pretty crack through the valley. How terrible is that?

 

[Steel1]

Cam lobes could be worn down. Given the cracked block engine has to be torn apart anyway so I guess you'll find out. Feel bad for you, that sucks.

 

[93silverlx50]

Anyone run a car with a crack through the lifter valley? How bad is it really? What are the possibilities if I buttoned it back up and ran the car like that? (I have to clue how long it's been cracked)

 

[Dan02gt]

I've never heard of a cam breaking in half but I guess it's possible. The fact that the valve train in the back half of the motor is not moving would definitely make me think that in your case it is broken. Add that to the crack and my advice would be to invest in a short block.

 

[MustangIIMatt]

Anyone run a car with a crack through the lifter valley? How bad is it really? What are the possibilities if I buttoned it back up and ran the car like that? (I have to clue how long it's been cracked)

It will only get worse. Time to start shopping for a replacement.

 

[Mustang5L5]

How much power were you running? Your crack is the typical spot most 5.0s tend to split at. Usually it happens in the 450-500HP range, and High RpM is usually the catalyst that starts it.

 

[vristang]

check that you don't have any stuck valves?
Time to tear that thing apart... salvage what you can, block is done.

 

[93silverlx50]

How much power were you running? Your crack is the typical spot most 5.0s tend to split at. Usually it happens in the 450-500HP range, and High RpM is usually the catalyst that starts it.

I dunno. Maybe 400 to 450. 306 block with TF Heads (ported), S Trim at about 14ish lbs of boost.

 

[93silverlx50]

check that you don't have any stuck valves?
Time to tear that thing apart... salvage what you can, block is done.

This sucks... lol.

 

[Mustang5L5]

I dunno. Maybe 400 to 450. 306 block with TF Heads (ported), S Trim at about 14ish lbs of boost.

Yup, that would split a block.

 

[mikestang63]

That's a nice planter you have there SIr.

 

[Trojan Horse]

It's time to invest in a Boss 302 or another aftermarket block if you plan on running forced induction at 14 psi.
The block you have as others have said is toast and if you continue running it you will only damage more parts when it completely fails, as it will probably sooner rather than later. Sorry about your bad luck.