losing my motor

[Dave C]

someone please tell me anything else that could be causing this. It's a 351m that is not firing on the number 4 cylinder. I replaced all the plugs, the plug wires, the cap, and the rotor. I can pull the plug wire on that cylinder and the motor runs the exact same. I will be doing a compression check in tomorrow but i'm hoping this is still a problem I can solve without tearing into the motor. Any ideas?

[Dave C]

with what I could do here I found out the following
The rocker arms are bolted down, nothing is loose
There is gas in the oil again

[ImNotRight]

Well, if you pulled the vavle cover then there goes the one other easy thing I could recommend, a pushrod falling out. (it actually seems to happen quite often)

BUT, considering all that, I'd say time for rings (or a hole in the piston), followed by burnt valves.

[Dave C]

I just did a compression check, it's at about 110 psi, so maybe the motor is salvageable after all. The current theory is that the lifters on that cylinder aren't pumping up and thats keeping it from firing.

[187racing]

check your valvesprings. Those engines break those pretty frequently and it will cause a miss.

[Dave C]

I was looking at the distributor and noticed the magnetic pickup for the ignition was loose. I can't remember what it's called but it's the piece that the vanes rotate against, the epoxy on it has broken loose and it's sliding around. think that could be the cause?

[wetnsloppy4x]

Those engines also like to bend pushrods. Make sure they're all straight as a precaution.

For a quick and dirty method of diagnosing lifter bleed down, try cranking the engine over with the valve cover off. Watch for rocker arm movement on the problem cylinder.

Oh, I almost forgot... Dave, does #4 have spark for sure? Try pulling a wire and use a screwdriver to ground it out.

[wetnsloppy4x]

Whoops, it looks like you just replied with your own answer while I was typing my last reply.

Look for damage on the inducer (little thingy with vanes). If it smacked the pickup module chances are it's wounded.