Squeek in my exhaust? WTF??

Damn that's a loud squeek. I don't start my new motors unless they have mufflers, so I can hear what's going on. That said, I'd muffle that thing before going any further (NO MORE STARTS!), and it should be a lot easier to diagnose. BUT, if you can hear that over that loud exhaust, I'd be concerned

 

heard that noise from an old 327 i had in a 36 chevy, it was a spun bearing.

 

Well lets see,... It's a small block Chevy,... also called a "Mouse" engine,...I would ***ume that the Mouse is trying to escape out of the exhaust.
A Rat (big block Chevy) sounds totally different,.. and are usually found in "rat rods"

o I would like to apologize in advance for the aforementioned post,... I just couldn't help it,....... )

 

that is loud.... have you even checked the oil yet? i mean, drain it and check it... not just dip stick.
groucho is right, better stop starting it up..

 

Dumb question: have you tried running it with the fan belts removed? Just thinking it could be the belt itself, water pump, alternator, etc.

 

Marty...
Pull the plugs, do a standard compression check.

1. The 'squeak' is at low R.P.M., (idle) so if it is a leak at the exhaust valve, you will find it.

2. As you have already isolated it to #5, it should be a matter of comparison with the rest. Good Hunting....

 

I had a 396 that sounded just like that it galled a rocker ball. If you have roller tip rockers that could be it.
Scott