Whats this sound!?!? New Motor... Video inside

[chrisf695]

I just got my 408 sbc running Saturday and Im getting this sound from it. Once its warmed up it goes away and if you give it throttle it goes away. I have good oil pressure and no misfires. Kinda baffled...

Things that come to mind... pistion slap from short skirts, exhaust leak, lifter clearance?

408 sbc startup noise - YouTube

Powerplay XLT Integra with 408 sbc - YouTube

Any help would be nice!

 

[Grandad]

Re: Whats this sound!?!? New Motor... Video inside

Hi Chris, I'm no expert but, those belts seem to have a lot of play in them. Is the tension correct? Stopping the first video shows quite a resonant wave in the belt at about the 19 - 20 second mark. - Grandad

 

[chrisf695]

Re: Whats this sound!?!? New Motor... Video inside

Wow... now that you said that... that is alot of play... Can that cause noise like this at all?

 

[Don S]

Re: Whats this sound!?!? New Motor... Video inside

Get a mechanics stethoscope and pinpoint where the sound is coming from exactly.
Kind of sounds like it's coming from the timing chain cover in the video.

 

[chrisf695]

Re: Whats this sound!?!? New Motor... Video inside

Get a mechanics stethoscope and pinpoint where the sound is coming from exactly.
Kind of sounds like it's coming from the timing chain cover in the video.

Ill pick a stethoscope tonight... but looks like its coming from the alt... the power steering isnt moving in the video and the belt is all uneven... looks chewed up...

 

[Grandad]

Re: Whats this sound!?!? New Motor... Video inside

Wow... now that you said that... that is alot of play... Can that cause noise like this at all?

I dunno if that's the cause of the noise, but if they're slack it can't be good for accessories or for the belts themselves. - Grandad

 

[Don S]

Re: Whats this sound!?!? New Motor... Video inside

Take the belts clear off and start it for a minute and see if it makes the noise. It won't overheat that quick.

If the noises are gone, you know where to start looking.