To start off I will flippantly comment that I need a new nickname: Dumb Kid. Now that you're in the proper frame of mind, let me continue.
I'm still hard at work with my '72 Super. I've tackled a few more things by now. I'm almost there. One thing I had to deal with was I needed a completely new set of engine tin, because the engine in mine came out of a baja that I also bought. I got the Baja first, but didn't like it. So I bought the '72 from a guy who agreed to a low price if I would take the engine out and return it to him.
So now you know why I needed new tin. I didn't even really know what tin pieces I needed or how they "should" fit. I did put all the tin on now although it was a tedious job and I had to back up a few times and start over when I realized a piece had to preceed another piece. I'm going to try to explain what I've done and what I now see and provide info so you can help but it's hard to get the info in here without rambling but I will try.
So I got it all back on and I got my carb to stop leaking (new accelerator pump diaphram) and I notice a couple of weird noises. One is a loud click sound that happens upon fast acceleration and it really has me worried but I'm going to save that for another post. The second sound is a vibration type sound. Like a buzz that happens for a second at certain RPM's. It's also quite loud but seems more innocuous than the click. The buzz is what I am going to focus on in this post.
Basically in order to get the tin on I had to remove about everything from the engine -- the carb, alternator, shroud (the only original tin I did have), intake manifold, exhaust. I put the new tin on and it's all fully bolted down. I used 10mm hex head bolts all around and I used lock washers to try to prevent losing a bolt and the tin that it supports. Everything is down tight and I doubt there is a problem of loose tin bolts.
At one point I removed the crank pulley bolt because I thought it was the only way to get the pulley tin behind the crank pulley. I tried to carefully pry the pulley off but I didn't want to screw it up so when it didn't come easy I put the bolt back on and just kept working the angles. I finally got the tin on. At one point I had every bit of tin all on but when I cranked the engine over there was a bad squeel. I figured out it was the fan rubbing inside the shroud. So I broke things back down and checked the fan. It seemed to wobble just a bit but would not normally bind. So when the alternator was clamped down it would pull on the shroud and cause it to bind. So I figured out that my shroud was not sitting down quite all the way. After fumbling about with the contact areas between the shroud tin and the case and the cylinder tins, I was able to get it to seat down good and the alternator bolted down and the fan no longer rubs. Whew. So again I put it all together. Started up fine this time with no odd noises.
However, I noticed after a couple of revs there is this bad vibration sound at about 2000 rpm. So I go back to the rear and pull the throttle and try to isolate. I couldn't figure it out. I grabbed a bunch of things that were away from the belt area to see if the sound would go away. I even grabbed the coil, and then remembered that you SHOULD NOT grab the coil. Boy that was fun. I noticed that as I pulled the throttle the belt would get kind of eccentric (like wobble or flip or whatever in it's track, as if loose). So I decided maybe I didn't tighten the crank pulley enough when I put it back on. I was at this point getting impatient so instead of going off to read I reasoned that it should be pretty tight, like as tight as the gland nut on the opposite side. I tightened it down about as tight as I could with an extension. I hope that was ok. Right at the end it seemed to slip a little so me being scared to death I just stopped and figured it was either tight enough or it was hosed. Either way not much I could do.
Repeat test. Belt seemed to flow a little better, noise seemed a little less. So I decided to try to tighten the belt. I removed the alternator pulley, moved two shims from the inside to outside, and retighted. I went back to the driver's seat and tested where I could see my tach. At first, the sound was the same, and was at about 2000 rpm. But I noticed as I moved up the rpm scale it would happen again a couple times (as if at a harmonic further up). After revving it a bit and playing with it the noise all but went away. The only way I could coax it out was to accelerate fast to 2000 and then release right as the tach needle want past the 2000 mark, then on the deceleration it would make the noise for a second.
It was getting late so I went in to watch Star Wars with my wife.
Next morning, renewed, I went back out and put in the two screws I realized I had forgotten on the bottom of the alternator shroud to fan shroud housing. It was a pain becuase these two screws are low and behind the intake manifold once everything is in right. I did get them in though with the help of my wife's small hands. Test. Still the noise. Damn. All night sleeping on it and that was the best I could do and it didn't work. Waste of a night's sleep if you ask me.
So wanting to get my wife in a better mood I say "get in and we'll go for a ride". It's not yet legal (I'm workin' on it) so I just back up on the lawn and forth again a few times. There that was our ride. Aren't you glad I bought this car????
My wife was feeling a little better and went in. I was feeling worse of course because I still don't know what's going on. So I went back and popped the deck lid. I notice that the belt had flipped during our little "excursion". I had revved it a few times, up to about 4000 as I went back and forth on the lawn. The belt flipped during this and was now tracking kind of upside down on the wrong side (the goodyear brand name letters on the belt invisible).
So guys my belt is pretty tight. I am pretty sure I understand the "half inch play" setting. You should be able to press on one side of the belt and get about a half inch deflection without pressing super hard. If anything I'd guess mine is a little tight.
However, I can tell you that when I accelerate rapidly the belt kind of goes haywire for a second. I am not really sure if that has anything to do with the vibration sound, but visually it seems the sound happens the same time as the belt is wobbling. I also can't pin point the source of the sound. It sounds as though it could be the tin vibrating. But perhaps it could be a bearing gone bad too. I'm not really that experienced with identifying sounds like this. It is coming from the area near the pully/belt area. If I press with a screwdriver on the tin where I would assume it could vibrate it doesn't seem to alleviate it, nor do I feel a super strong vibration as if I found the source.
My biggest concern right now is the belt because it wigs out and because it flipped on me. Do you think it is still too loose? Or did it flip because I have it too tight??
I'm just a Dumb Kid and I don't know. I'm still learning about everything. I will screw up a lot more I'm sure of it. I hope although this was long I was able to spice it up a bit. I just wanted to make sure you know what I know so you have something to go on.
TIA.
Chronologic