Ticking sound -- NOT A SLIPPED SLEEVE
#41
05-06-2016, 08:52 AM
I don't buy the argument that valve train noise would have stopped when the HT line was disconnected. If it's something mechanical in the valve train then it's going to happen regardless of spark.
That said, I would start with exhaust gaskets. Simpler to address. Spray them with copper coat first.
That said, I would start with exhaust gaskets. Simpler to address. Spray them with copper coat first.
#42
05-06-2016, 09:03 AM
I don't buy the argument that valve train noise would have stopped when the HT line was disconnected. If it's something mechanical in the valve train then it's going to happen regardless of spark.
That said, I would start with exhaust gaskets. Simpler to address. Spray them with copper coat first.
That said, I would start with exhaust gaskets. Simpler to address. Spray them with copper coat first.
what do you mean you "don't buy that?"
Does your engine differ in that it has 1 set of valves for all 8 cylinders? I'm pretty sure that mine has a set for each cylinder, so unless it is the rocker arm as a whole, valve train noise in a lot of circumstances can be isolated to a specific cylinder.
#43
05-06-2016, 09:10 AM
I don't buy the argument that valve train noise would have stopped when the HT line was disconnected. If it's something mechanical in the valve train then it's going to happen regardless of spark.
That said, I would start with exhaust gaskets. Simpler to address. Spray them with copper coat first.
That said, I would start with exhaust gaskets. Simpler to address. Spray them with copper coat first.
I'll be finding my 12mm this afternoon and check them. I still feel it is a mechanical issue, though because it sounds like metal tapping. The sound seeks to be coming from the head and I was pleasantly surprised to not have any exhaust sound on the first startup, but honestly I have had exhaust sounds before and couldn't even figure out which side they were coming from.
#44
05-06-2016, 09:25 AM
If the noise is in the valve train, it should have stopped on that cylinder when you pulled the HT wire. Now, if the whole rocker arm assembly were not torqued down, maybe. What about the exhaust manifold and gaskets? did you check the torque on those bolts again? it's pretty loud...maybe exhaust leak
Last edited by Charlie_V; 05-06-2016 at 09:51 AM.
#45
05-06-2016, 12:14 PM
Faulty/ collapsed cam follower, rocker arm pushrod insert/s worn, were the followers replaced with genuine ones or generic GM ones? The other issue that can arrise after machining deck heights and cylinder heads is that lifter clearances become too tight . Have a read https://www.google.com.au/url?sa=t&s...97D6vqVO8gixkQ
this article that he posted has mostly to do with adjusting lifters so I don't know what hes thinking, really. But I didn't want to ask. Obviously he thinks that the preload has changed since you have swapped so many parts, but I don't know anything about that, myself. You aren't going to adjust your lifters but if you at lease check your clearances you may find something. That new cam may not be syncing/vibe'ing with the stock valve train components. The mechanic that advised you to upgrade the springs....why don't you give him a call and tell him about the tapping noise and see what he thinks.
this article that he posted has mostly to do with adjusting lifters so I don't know what hes thinking, really. But I didn't want to ask. Obviously he thinks that the preload has changed since you have swapped so many parts, but I don't know anything about that, myself. You aren't going to adjust your lifters but if you at lease check your clearances you may find something. That new cam may not be syncing/vibe'ing with the stock valve train components. The mechanic that advised you to upgrade the springs....why don't you give him a call and tell him about the tapping noise and see what he thinks.
Last edited by chubbs878; 05-06-2016 at 12:28 PM.
#46
05-06-2016, 12:38 PM
Faulty/ collapsed cam follower, rocker arm pushrod insert/s worn, were the followers replaced with genuine ones or generic GM ones? The other issue that can arrise after machining deck heights and cylinder heads is that lifter clearances become too tight . Have a read https://www.google.com.au/url?sa=t&s...97D6vqVO8gixkQ
this article that he posted has mostly to do with adjusting lifters so I don't know what hes thinking, really. But I didn't want to ask. Obviously he thinks that the preload has changed since you have swapped so many parts, but I don't know anything about that, myself. You aren't going to adjust your lifters but if you at lease check your clearances you may find something. That new cam may not be syncing/vibe'ing with the stock valve train components. The mechanic that advised you to upgrade the springs....why don't you give him a call and tell him about the tapping noise and see what he thinks.
this article that he posted has mostly to do with adjusting lifters so I don't know what hes thinking, really. But I didn't want to ask. Obviously he thinks that the preload has changed since you have swapped so many parts, but I don't know anything about that, myself. You aren't going to adjust your lifters but if you at lease check your clearances you may find something. That new cam may not be syncing/vibe'ing with the stock valve train components. The mechanic that advised you to upgrade the springs....why don't you give him a call and tell him about the tapping noise and see what he thinks.
#47
05-06-2016, 12:39 PM
#48
05-06-2016, 12:48 PM
what do you mean you "don't buy that?"
Does your engine differ in that it has 1 set of valves for all 8 cylinders? I'm pretty sure that mine has a set for each cylinder, so unless it is the rocker arm as a whole, valve train noise in a lot of circumstances can be isolated to a specific cylinder.
Does your engine differ in that it has 1 set of valves for all 8 cylinders? I'm pretty sure that mine has a set for each cylinder, so unless it is the rocker arm as a whole, valve train noise in a lot of circumstances can be isolated to a specific cylinder.
I'm not in any way saying that valve train noise cannot be isolated to a single cylinder; I'm saying that pulling off the HT lead won't aid you with that isolation unless the noise is something to do with a spark condition.
#50
05-06-2016, 01:23 PM
I mean that if the noise is a mechanical origin, it will occur regardless of spark (as I said). Pulling off the HT lead is not going to affect the valve train.
I'm not in any way saying that valve train noise cannot be isolated to a single cylinder; I'm saying that pulling off the HT lead won't aid you with that isolation unless the noise is something to do with a spark condition.
I'm not in any way saying that valve train noise cannot be isolated to a single cylinder; I'm saying that pulling off the HT lead won't aid you with that isolation unless the noise is something to do with a spark condition.
I would love to debate that. I'm a little busy at work now so it will have to wait.