What is this motor noise?

[GTBill]

chain noise? - YouTube

it's on my 2003 gt. i pieced the motor together. it was making this noise, so i figured it was the timing chain tensioners. I took the timing cover off, sure enough one of them wasn't sealing. i bought some of the metal, ratcheting tensioners, put them on, and cranked the engine to watch them "pressure up".

well, the engine is still making the exact same noise. It only does it at the RPMs in the video, around 2,500-3,500. any ideas on what this noise is?

thanks

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[NasteeNate]

Hmmm, doesn't sound more like stuck lifter? If it was the timing chain wouldn't make the noise all the time, and not be RPM dependent?

 

[GTBill]

im not sure, i figured at that RPM the chain is moving fast enough to slap the inside of the timing cover, and be audible. any faster and it's moving to fast. IM NOT SURE, thats just a thought.

 

[DDogsrt461BLK]

rod bearing........................

 

[ncbadboi]

I agree with DDog, mine made the same noise at the beginning,.......and then i shot a rod through my head. good times.....i got a termy engine to replace everything.

 

[NasteeNate]

bad bearing is the worst possible scenario, but they do sound like that.

 

[Kenne Bell]

That sounds a lot like a rod.

 

[jleews6]

That sounds a lot like a rod.

This,, or it could be a wrist pin. If you put a load on it and it goes away it might be the pin. I have also seen a piston make that same noise. :shrug:

 

[1QUICK10TH]

I agree with DDog, mine made the same noise at the beginning,.......and then i shot a rod through my head. good times.....i got a termy engine to replace everything.

you shot a rod through the head? Doubt it....

That noise is a rod bearing

 

[GTBill]

thanks for the input.

update: i decided on a little WOT action, it made the noise all the way up to about 5k before i decided that was enough....

any more input?

 

[SeikenFreak]

Weird. This is the first thing I've seen that describes the noise I've been dealing with.

Mine does it the loudest when the engine is cold. Then it mostly or completely goes away when its warmed up. Motor has about 3-4k miles on it. Mine does it around 2-3k rpms.. Putting more load on it makes it go away. I've got good oil pressure. Its been doing it for quite awhile now so I've kind of started to ignore it/keep it under 2k rpms til its warmed up. I've rev'd it out more then a few times and its been through a number of dyno pulls and nothing has happened yet. We'll know for sure when I take it to an HPDE on the 22nd.

Mine isn't as loud as yours in the video though. I had a friend listen to the current noise and he suggested maybe a bad lifter. Also described it to another shop owner and he also said a lifter. Also mines a DOHC.

Your video is what my rod knock sounded like prior to getting the motor rebuilt.

 

[sam92lx]

I'm going with a rod.

 

[jrd699]

Defiantly rod knock 100%

 

[megameGT500]

thanks for the input.

update: i decided on a little WOT action, it made the noise all the way up to about 5k before i decided that was enough....

any more input?

Good idea. I would go with rod bearing.

 

[1QUICK10TH]

thanks for the input.

update: i decided on a little WOT action, it made the noise all the way up to about 5k before i decided that was enough....

any more input?

Thats the worst idea you could have come up with.