Ok I pulled the engine apart and guess what!!! nothing wrong. My initial thought was valve train noise but listening to it while running with the valve covers off I couldn't tell. I could hear the noise down low but if I put my ear on the intake I could hear loud clicking. Someone mentioned it might be a valve and that might be. I can tell you the exhaust gaskets were new and didnt show any signs of leaks.

It sounded like loose rocker arms but all were tight. Maybe like Smitty said I needed to take it out and see what happens. This engine had milkshake in it and some of that could still be in the lifters. However its if its a valve I dont want one to drop into the cylinder so I guess Im gonna spend more money to get them checked. Im thinking now I need to have the heads checked or use a known good set now. I have the original gen v 454 mag heads that have the same casting number that had a valve job done. I may use them next time if they are the same heads from gen v to vi.

However I did find that the timing chain had slack in it. I dont think it would have been enough to hit the cover but anything is possible. It was enough for me to change the timing chain.

Tom you have these engines and they sound the same? both of them? The 454 mag didnt have this sound at one time. and Im afraid to run it like that. My intial thought was the lifters were loosing prime or still had milkshake in it causing it to not pump up but when I pulled the valve covers off while running all were squirting good oil.

Mine are Gen IV engines and have always sounded like that. I've run the boat 160 hours over the last three seasons with no issues. I refreshed the heads on the port engine because of gasket seepage that was evident on the block. The sound never changed.

Do you know if the heads have been off before? The valvetrain isn't adjustable and if the heads have been shaved during a rebuild, that could contribute, maybe. I know both of mine have had heads done (one was from a stuck valve and the other from burning oil).

I had the heads off and had them pressure checked. I installed marine head gaskets but I didnt have the heads or block decked as the engine was said to be good. Now Im starting ot think that sound might be from the heads. I couldnt find anything else to state otherwise and as Articfriends stated the speed of the tick leans towards cam side up. Im having the engine rebuilt now and will probably go .030, new pistons, vatted, re-ring bearing it and put it back together. IF i still have that tick Im gonna run it. I do plan on using the gen v heads off the 454 mag mpi this time. I had a 3 angle valve job done on them and the springs checked.

Ive never seen a factory single roller chain that DIDNT look loose as Fuk, thats pretty normal for these.

Well I might have to see if i can find a better replacement.

What does this mean ?

I just means its not locked up. I was moving very very slowly just not spinning freely like it did but I do get it.