Hey guys. Some of you may have seen my posting a few weeks ago about my purchased rebuilt motor that wouldn't idle. I Changed out the MAP sensor and fixed that problem but only to find out that a cam gear was bent. I didn't really have much time to fix it so I had some one who I TRUSTED (notice the past tense) to take care of changing the gear for me and putting it back together. Well when time came to test it (I still had the timing cover off to inspect it), I inspected the timing marks and everything lined up. I fired it up only to be greeted by the loudest clanking my car has ever made. Even when I threw a rod bearing it wasn't that loud. I immediately shut it off not wanting to cause more damage. Well after some staring and thinking, I realized that the crank marks lined up right but it wasn't at TDC for piston #1. I turned it a full revolution and THEN piston #1 was at TDC. Now i've read some posting that say that the car wouldn't start if the timing was off by 180 degrees but I beg to differ. The car definitely started but not in a way i'd like it to. I immediately thought i'd bent some valves but thought it was worth a shot to put it in time and try again. I did and the car ran "smoother" but the noise was still very much present. It immediately revved to around 3,000rpms so I turned it off after like 3 seconds. Well a few cuss words later, I started pulling off the head. I was so looking forward to seeing some bent valves so I would at least know what was wrong and could actually get some sleep at night. Well the pistons and valves looked brand new without a single scratch on them. I am completely clueless as to what is wrong and at my wits end with this car. I am so close to just giving up and I ALWAYS finish what I start. I guess my question is could the valves be damaged interally (hitting against the guides/seals) where I can't see it and cause a loud noise like this??? I don't think so but i'm not sure. I'm going to take the head to a machine shop and have them inspect the head but it looks brand new! Any info or comments are more than welcome and needed. Thanks Guys!!!

If it wont cost much have the head inspected for sure. I would also consider checking out your bearings and rods. Could be a bent rod possibly.

How did the valve train look, did you have any rockers rattling or something?

A valve is more likely to bend from contact than a rod so I'd all but rule that out. I'm putting my money on something loose in the head.

The valve train looked good. The cams and rockers were tight and everything seemed good. I was concerned that maybe oil wasn't flowing to the top but everything was well lubed when I pulled the valve cover. Tomorrow i'm gonna pull of the inspection plate covering the flywheel to see if there's anything there that would cause this problem. If that doesn't help, i'm gonna drop the pan AGAIN and see how things look. I don't think that is where the problem is but I don't want to rule out the possibility. Thanks for all your help guys!

Could be a loose bolt on the flexplate did not think about that.

Could be a whole slew of things causing the noise.

BTW the cams werent 180* off. Crank must rotate 2X to reach cam alignment marks. When timed the crank at TDC and cam gears lined up, one rotation of the crank will result in the marks appearing to be 180* off.

So I dropped the pan today and everything looks perfect. no play in the rods and the whole assembly moves up and down smoothly. I am stumped. I'm glad to know that my new motor is undamaged but still sucks not knowing where to go from here. All I can think of is maybe the flywheel is damaged but have not checked it out yet. I will keep you guys updated.

so your saying you can "feel" .010 of bearign clearance just by sticking your fingers in there?

Dropping the pan and looking around doesnt tell you shit if you have excess rod play. The only signs your going to see are a rod bearing spun or bearing metal in the oil pan. It does not prove there isnt a problem present in the bearings causing a knocking.