Newly started...now knocking noise...FML(video)

[LSDrift]

So I just today got my motor started and idling. It idles very nicely and I thought everything was awesome and moving in the right direction. A bit ago I was letting it warm up and as it did, I noticed a knocking sound coming from what to me sounds like lower internals...

I don't know exactly what it is but it made me sick to my stomach to hear it just as I get my setup finally running...

Excuse my ghetto intake piping and lack of exhaust but here's a video of the sound.

[LSDrift]

Ok so I've been searching around and watching other videos and my guess is noisy lifters. Got all worked up for nothing...hopefully anyhow...anyone else have thoughts on the noise?

[Yellow4g63]

Did you crank the motor to build up oil psi before you fired it up? Sounds like lifters to me.

[robbie2883]

sounds kind of deep to be lifters...but it's kind of hard to decern from the video. lifters will be more of a ticking sound and it will definitely sound like it's coming from the top end. rod knock will be a deeper sound but could still sound like it's coming from top end. the only way to know for sure is to pull the valve covers and check the valve lash and if that's good then pull the oil pan and look for a lose rod.


oh...and rb25's will have some ticking for the first couple minutes while the hydrolic lifters prime. (unless you primed them yourself)

[LSDrift]

Well I let it warm up to actual running temperature yesterday and the sound seems to be lessened. When the motor is cold it's hard to discern the sound but in the period of semi-warmness to fully warm transition is when it's loudest...kinda odd...but anyhow, one of the main reasons I think it's not rod knock (or would like to think anyhow) is that it doesn't get worse with revs and isn't quite as rapid as some other rod knock videos I've watched lately. Now I realize that makes me no expert but it helps me sleep at night haha. Anyhow, I've read a couple things about having a flat lifter? Could this be the culprit?

Thanks for your input guys!

Oh and PS: I'm going to continue putting the engine together as if nothing was wrong at this point because there's not much else I can do. So when I finally get an exhaust system installed I'll be listening closer to the sound and I'll post another video...hopefully it'll be easier to hear then, or maybe by that time it'll have disappeared!? haha we'll see I guess...

[SlowKoop]

Whats your vacuum at? When my vacuum line for my boost gauge came off one day it sounded kind of similar.

[LSDrift]

Well with my ghetto PVC piping my boost gauge says about 16 inHg at steady idle. If I rev it up a bit it'll almost hit 20.

[SlowKoop]

That could be your problem. I would check that after everything is back together.

[robbie2883]

that's an obvious mechanical knocking/tapping i don't see any vacuum issues causing that. let me ask you though. do you have stock internals or aftermarket?

[LSDrift]

It's all stock internals. I haven't touched the interior outside of a new headgasket, ARP studs, and I took the pan off because it was dented and I thought it was leaking...turns out it was just a bad gasket on the plug.

[robbie2883]

well like i said...pull the valve covers and check your valve lash. it's not hard. and rod knock speed is directly correlated to rpm. you can always do the long handled screwdriver trick to track down the location of the sound.

[LSDrift]

Yeah I'll have to check it out. Do you think it could be a crappy turbo inlet gasket causing an exhaust leak? I was just thinking about it and when I took everything apart it was pretty sad looking but I decided to do use it anyhow...maybe I'm just making s**t up now haha...

[RRRRB]

try unplugging the coils one at a time while its running, sometimes that will take enough load off that paticular cylinder and the knock will go away