Thread: new engine started up, weird noise from flywheel area.

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Howdy first post here. I have a 1968 Chevy c20. I just put in a new 350/350 crate motor. It started (with a little help and info from your forum). I am stopping the clacking noise from the valves right now. It has a timing gears and is super noisy. As I am getting rid of the valve clacking noises, I heard this noise coming from the bottom of the flywheel area. It's clicking and clacking. Loud noise but coming from the small pan under the flywheel. (I used a hose up to my ear to find where the noise was coming from.) I had the 4spd granny trans rebuilt and it seems to work fine, just this horrible noise. It has a new clutch. When I push in the clutch or engage the gears it all works fine. The noise gets worse if it's in neutral. The noise is not bad if it's in gear going down the street. Clutch adjustment? Not sure what else it could be? Something put together wrong? Help? ?

Throw out bearing in backwards? or maybe just shot. Be my first thought.

Not sure what it is. How can I tell if it's in backwards? Or just shot?

The noise is present when it's in neutral also. Wouldn't the noise happen only when you applied the clutch pedal?

if the bearing was in backwards, shouldn't make a noise unless you was mashing the clutch. make sure the flywheel is not hitting the dust cover. make sure the throw out bearing is not turning all of the time. in neutral. and going down the road it shouldn't be turning. make sure the starter is completely disengaged.

I may be way off on this one, but it sounds like the pilot shaft might have galled roller bearings internally.
I have to wonder why, with a new engine you went gear drive. I have had them and I do not like them at all. Just my feeling.
My other thought might be a loose flywheel at the hub. However, when I had one, it had more of a feel through the pedal rather than audible.
After all that work, that must be very frustrating. I just spent two days diagnosing a missplaced spark plug wire. After all the engines I have built, cars I have restored, rods I have built, I had two plugs off on the cap. It is a big block, and I have not had a big block for years.
Like Duh!!!!
I hope your fix is that simple.

Not necessarily. A bad throw out bearing could and most times will make noise all the time. Sometimes worse when the pedal is mashed, sometimes not. Making sure the starter is disengaged is a pretty good on also. One that was in backwards can make constant noises also. Learned that one the hard way as a youngster. Although not always. Like has been said though. I'd shut 'er down and remove the dust cover and see if you can see any fresh marks anywhere. Use some safety glasses and turn the motor by hand and look, if you don't see anything I would probably lean towards the bearing, but this is also a guess based on online info. It's hard to troubleshoot online or over the phone. I can't really hear what the noise sounds like, but these are a few things that it could be.

Originally posted by urotu
Not necessarily. A bad throw out bearing could and most times will make noise all the time. Sometimes worse when the pedal is mashed, sometimes not. Making sure the starter is disengaged is a pretty good on also. One that was in backwards can make constant noises also. Learned that one the hard way as a youngster. Although not always. Like has been said though. I'd shut 'er down and remove the dust cover and see if you can see any fresh marks anywhere. Use some safety glasses and turn the motor by hand and look, if you don't see anything I would probably lean towards the bearing, but this is also a guess based on online info. It's hard to troubleshoot online or over the phone. I can't really hear what the noise sounds like, but these are a few things that it could be.

urotu, if you have the throw out bearing adj. properly it wouldn't be turning at all in neutral, that's based on a few 100 clutch and pp installations ive done over the years.

Thanks for the help everyone. I'm so fricking close on finishing this. I knew it wasn't going to be simple. I'll pull the cover off in the morning. I would like to think I didn't put it in backwards. When I push in the pedal it makes a slightly louder (more pronounced) noise. Sounds like a muffled valve noise, clickity clack, very fast. I am kind of slow...so... what is it when the starter is not completely disengaged? As for the gear drive...It is not for the performance. I just like the sick whinny noise and it pisses people off sometimes. All the better!

Lt1s10...how would I adjust it properly? I like this site. It's like having my dad help me (he passed away 10 years ago.) Thanks!

Originally posted by pmjan
Lt1s10 work with...how would I adjust it properly? I like this site. It's like having my dad help me (he passed away 10 years ago.) Thanks!

sorry to heare about your dad, glade to help if i can, but im assuming you have a manuel linkage to work with, go down to where the throwout bearing folk comes out of the bellhousen and where the clutch rod meets the fork and spread them apart, should have about 1/16 to 1/8 of an inch gap between them, if not adj. it. if you have anything dif than this let me know.
read this other stread and see if you see anything. you dont want your bearing turning all of the time, its not made to run that much.

http://www.clubhotrod.com/forums/t12...-&pagenumber=1

Hope you checked the flywheel pilot bearing/bushing.

Originally posted by lt1s10
make sure the starter is completely disengaged.

I had this prob on my 350, it turned out that the starter gear was hitting the flywheel. Took off starter and the spring that pushes the starter was wore out and the gear was moving very easily back and forth. May not be your problem, but it has been my experience.

Originally posted by lt1s10
urotu, if you have the throw out bearing adj. properly it wouldn't be turning at all in neutral, that's based on a few 100 clutch and pp installations ive done over the years.

lt1s10 based on the few 100 clutches I have done over the years, including mediu and heavy duty I can tell you from experience that a throw out bearing can and will make noise in nuetral, in gear, with the clutch in, with the clutch out, you name it. Just because the transmissio is not in gear does not mean that the clutch parts quit working. The clutch plates are what engage and disengage to make your car move. Now, in theory, you are correct, if the bearing is in adjustment it should not be turning, in my experience there are very few people who adjust there clutches properly, especially since the introduction of the hydraulic clutch and most folks don't have to worry about it anymore, so most folks don't know how to adjust a manual clutch anymore, much less a throwout bearing. Now all this being said, what do you think the clutch parts do when you engage and disengage the clutch with the car in nuetral, they do exactly the same thing that they do when you have it in gear. So this being said, you bet the throwout bearings can and will make noise in nuetral.

I'm sorry If I made a quick diagnosis that you didn't like, but was making an online diagnosis based on the little info that was provided, just like you. This sounded like one of the more reasonable things to look at. I never asked if the noise changes with the rpm of the engine, does it?

Ok, had two games of little league for the kids now I can play. I took her up and pulled the bottom flywheel cover. The starter was not engaged all the time and I saw no visable worn, scratch marks etc. on anything. Looked the same when I put it in. The throwout bearing is in right. Whew! The flimsy piece of metal that goes on the bottom engine facing side of the flywheel is shaking like a banshie making the noise. It looks like something is hitting it as the flywheel turns. The metal cover looks straight and all of the screws are in. I'm pulling the starter and am going to try to see what is hitting it. Any ideas as to what would hit it? What did I put together wrong? Lt1s10- I have the proper gap on the linkage...I'd like to say that I did it that way on purpose but....
The noise changes witht he RPM's, something is hitting on the front metal sheet. I'll check the metal first then....