Help!! Engine Miss

Tony Curcio · 01-28-2012, 06:35 PM

It sounds like you've isolated everything external to the engine- after 67 posts it's hard to take it all in.

As you said, the valve train is your next suspect. You've had the valve covers off- did you run the engine while they were off? This is a quick way to see if a lobe is flattened, a pushrod bent, a stud pulled out of its threads, or a broken valve spring. You'd probably be able to spot these things even if you just cranked it with the covers off. Any of these will make a popping sound in a consistent rhythm.

An overtight valve just sounds like crap, hard to describe, but a valve is not closing, so it's just weak and shakey.

One more thing I remember chasing long ago- a head gasket that is blown between two cylinders. Spits out the exhaust and intake of the two affected cylinders.

All of the above have a distinctive sound. If it was possible to post an audio file, many here would probably recognize it.

Hope you solve it soon, and hope you'll post it when you do.

01-28-2012, 06:35 PM	#31
Tony Curcio Member Join Date: Mar 2002 Location: West Chester, PA Posts: 271 Likes: 1 Liked 4 Times in 1 Post	Re: Help!! Engine Miss It sounds like you've isolated everything external to the engine- after 67 posts it's hard to take it all in. As you said, the valve train is your next suspect. You've had the valve covers off- did you run the engine while they were off? This is a quick way to see if a lobe is flattened, a pushrod bent, a stud pulled out of its threads, or a broken valve spring. You'd probably be able to spot these things even if you just cranked it with the covers off. Any of these will make a popping sound in a consistent rhythm. An overtight valve just sounds like crap, hard to describe, but a valve is not closing, so it's just weak and shakey. One more thing I remember chasing long ago- a head gasket that is blown between two cylinders. Spits out the exhaust and intake of the two affected cylinders. All of the above have a distinctive sound. If it was possible to post an audio file, many here would probably recognize it. Hope you solve it soon, and hope you'll post it when you do. __________________ Tony Curcio 1860 STK