Timing chail/ camshaft problem

[metalhd]

Hi, new here

however I have a 97 v8 and the front bank of cylinders is not firing and the timing chain and camshaft are not moving.
any and all help would be greatly appreciated!

 

[St Louis SHO]

It now needs an engine. The cam sprocket has spun on the camshaft causing the valves to smash the pistons.

 

[luigisho]

Welcome. Unfortunately what's stated above is correct. There is a cam defect that has a welding fix but it has to be done before the camshaft/sprocket fails.

 

[mustangracer91]

yeah, happened to me too, I bought mine and less than a week later, idling in my driveway...it stalled out and never started again, checked it out, and the back cyl head did the same thing and my back cylinders, pistons and valves are *****'d.

 

[metalhd]

Great, not eactly what I wanted to hear, but thanks. One question, I pulled the front valve cover and bumped the starter, the whole timing chain that drives the cam is not moving either, so is the actual break someplace else than the cam? I understand what you are telling me, and I expected to see a broken cam, but was surprised that the timing chain wasn't moving either.

Next question, what does it typically cost to have this fixed?

 

[siebert37]

Someone can correct me if im wrong but basically the sprocket on the cam slips, not breaks. Therefore the timing is off on the valves, and since this is an intereference engine, the pistons come into contact with the valves and bend the valves. I would guess that the reason why the chain is not moving is because one or many of the pistons are lodged against the valves.

 

[SHODWN]

Great, not eactly what I wanted to hear, but thanks. One question, I pulled the front valve cover and bumped the starter, the whole timing chain that drives the cam is not moving either, so is the actual break someplace else than the cam? I understand what you are telling me, and I expected to see a broken cam, but was surprised that the timing chain wasn't moving either.

Next question, what does it typically cost to have this fixed?

HUH? The Large chain is not turning? JIC, with the valve covers off you will see three chains, 1 large chain that wraps through the motor and drives two large sprockets, one on the end of each cam. You will also see two small chains that tie the two cams together in each head.. what chain is not moving?

100% of the time its a small chain that ties the two cams together that will not be moving.. if the larger chain is not moving you have another issue. and really after thinking about it, the only way for that to happen would be a broken crankshaft timing sprocket. But Ive never heard of anything like that yet..

 

[metalhd]

What I did was remove the front valve cover (well, lift up actually) and while having someone bumping the starter (the motor does turn over freely) watched the chain and sprocket on the passenger side of the engine compartment while the motor was turned over. This is the chain I am refering to that did not move. Is the main drive sprocket on the driver side of the motor? Was I looking at the wrong side? At the time, seeing that left me rather peeved and not wanting to look anymore. The motor will run as it is, albeit very poorly.

 

[rubydist]

The chain that you were seeing is the chain that runs between the intake and exhaust cams on the front bank. It is not moving because the sprocket on the cam that is driven by the long chain has spun on the cam.

If you were lucky, you can pull off the head and replace it with a good one. If you were not lucky, there will be damage to pistons and/or rods that will require the engine be replaced.

In either case, make sure you have the cam sprockets welded as soon as you get it together, to avoid a repeat experience.

 

[venom]

What I did was remove the front valve cover (well, lift up actually) and while having someone bumping the starter (the motor does turn over freely) watched the chain and sprocket on the passenger side of the engine compartment while the motor was turned over. This is the chain I am refering to that did not move. Is the main drive sprocket on the driver side of the motor? Was I looking at the wrong side? At the time, seeing that left me rather peeved and not wanting to look anymore. The motor will run as it is, albeit very poorly.

You can see the main timing chain that runs around the crank through the oil fill hole with the front valve cover installed. The other chain is not visible through there (at least not easily). Rather than deal with the valve cover holding up and crap just remove the fill cap and use a flashlight through there to confirm that chain is moving when the starter is bumped. On the other end of that head is the water pump pulley, now confirm it IS NOT Turning when the starter is bumped.

If so you have just confirmed that at least 6 valves in that head are probably bent and one of the cams has failed.