[retro_lopez8]

Hey everyone, my names Jose, and Im no mechanic, but Ive pretty much done all the basic removal/ installation and minor troubleshooting of a basic chevy engine. I recently purchased a new 305 block , that was sitting in an old truck. The block is supposed to be a NAPA crate engine, rarely used. When I purchased it, the guy fired it up for me and it sounded fine. When I removed the oil pan, I found it loaded with sludge, water and goo. However the pickup tube had fallen off . Now its been reinstalled into my 84 truck, and Ive yet to properly have a professional tune it, but It makes a large "clunking" noise. Everythings been torqued and tightened, Ive inspected all around the engine bay for a loose item that might cause this, but It sounds like it might be coming from inside the block. Is there a distinct sound to having a piston rod bent? would my situation call for that scenario if the pick up tube was not installed? Any advice would be greatly appreciated. Its been about 5 years since I messed around with mechanics, and even then I was still a rookie. THanks, Jose.

[68NovaSS]

From what you said, I would lean towards wiped bearings. If he ran it with water in the pan it was just long enough for you to hear it, and probably shut it off just in time. Without hearing it, that's just an opinion. Does the motor have oil pressure now? if so, how much?

If you didn't hydraulic the motor since he ran it, I doubt you have bent a rod!

[ssmonty]

If your sure its the same engine you heard running before without a knock, take another look at the flexplate/flywheel area for loose bolts.
"water and goo. However the pickup tube had fallen off" doesn't sound too good for the bearings. The crap might have been so thick that it took up the slop in the bearings until it got hot.
I would drop the pan and wiggle the rods to see if they have any play.
Good luck!
ssmonty
PS I see you beat me to it 68novaSS,

[retro_lopez8]

@ 68NovaSS, Thanks alot! Well thats good to know about the hydrolock. No I didnt run it till I had replaced a few of the gaskets. I should have checked the main bearings ,and made sure they were torqued down properly while the block was already out. So by wiped bearing, you mean maybe the crank has play and bearings might be worn out? Also Ill repost on the exact oil pressure. Thanks alot, Jose.

[retro_lopez8]

Hey Monty Thanks alot as well! It was the same block because I helped remove and bring home. But now that I think of it, although he only ran it for a while , I never heard the clunking sound then. Ill double check on the flywheel, hadnt thought of looking there.