Transmission, Clutch or Engine Noise - VIDEO

Is this a new sound? Is anything new or changed?
If it's starter or bendix it's only three bolts to check.
 
The sound is way too heavy to be a broken starter drive bolt being struck by the flywheel's ring gear teeth. Besides, it sounds as if the noise is coming from the top of the bellhousing, not below where a broken bolt would be living. I've seen this problem many times before and it is almost always because the flywheel ring gear has moved forward from the ledge around the flywheel's circumference. After thousands of times that the Bendix strikes the ring gear to start the engine, the constant force against the backside of the ring gear pushes against the ring gear and tries to move it forward. If the ring gear is slightly oversized (as off-shore ring gears were for many years in the 1970's-1990's) or the ring gear has broken in one spot, the gear will get c*cked at an angle. Every time that forward-most part of the flywheel comes around to the top of the flywheel housing, it strikes a re-enforcing rib or other parts of the cast iron housing, causing the noise you are hearing.
To check, remove the starter again. Look into the flywheel opening (where the starter was mounted) at the ring gear and the ledge behind it. If there is any gap, take a heavy hammer and a large punch and drive the ring gear back towards the rear of the car until it bottoms out against that ledge. Hand-crank the engine a few degrees and check again. The gear is most likely c*cked in only one place, which is why the banging noise is intermittent. Keep turning the flywheel until you find the spot where there is a large gap between the ring gear and the ledge behind it. It'll be obvious. You should not be able to put even a very thin feeler gauge between the gear and the ledge.
Once you have driven the errant ring gear back into place all around the flywheel's circumference, put the starter back on and start the engine. That should solve your problem, if what I am hearing in the video is correct. Should the ring gear loosen up again down the road, you'll have to drill, tap and stake the ring gear to the flywheel ledge. But, that's another story. Check this suggestion out first before worrying about that.
Marshall
 
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put a shorter bolt in the starter hole next to the block.....sounds like the flywheel is hitting the bolt that is in there. take a 3 foot piece of broomstick ....put one end on what ever you want to listen to and your ear on the other end and the sound will travel to your ear, that way you can isolate were the sounds are coming from
 
"When I mash the clutch as far down as it will go the sound diminishes a fair amount."
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is this still an accurate statement taken off your other thread?
what happens when working the clutch in neutral same thing?

when pushing the clutch in the input shaft of the trans stops or slows. (depends on overall clutch condition and adjustment, curb idle speed).. maybe its a trans bearing. did you check the trans fluid level ?
 
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Well, I would have bet the farm on the ring gear having moved because I didn't want to suggest the other possible cause of such a racket that I have heard in Model A drivetrains. I was hoping the trouble lay with the ring gear, as that is an easy fix. The other suggestion I am hesitant to make - because you aren't going to like it - requires dropping the oil pan. The knocking noise is a metallic sound, which I fear is the oil dip tray being struck by one or more connecting rods as they revolve through their arc. I had this happen to me once (and ONLY ONCE!) and it was my own darned fault. I failed to seat the oil dipper tray's sides into the pan's grooves along each side. Apparently I had placed the tray in deep enough that it wasn't obvious to me, but not good enough to seat the raised rails into the pan's depressions along the side. What happened after all was buttoned up was nothing for a while. Then a gradual metallic tapping started that degenerated into a banging until it sounded like your engine does now. The dipper tray - because I had not seated it properly - was tipping at an angle so that the revolving crankshaft would strike it via one or two connecting rods. All of the turbulence inside the crankcase had apparently lifted one end of the dipper tray up enough for this happen. It doesn't need to move far upwards to come into contact with the bottom cap of the connecting rod. Bang, bang, bang, it went - like yours. Since this condition has existed since you bought the car, I would suspect the previous owner either couldn't figure out what he had done wrong in assembling the engine, or he knew and didn't want to go through the fuss and mess of removing the oil pan while the engine was in the car. It's a dirty, disgusting, uncomfortable job! But at least when you have the pan down, you can check the connecting rod adjustment. So, it won't be a total loss. :)
To check for this condition, have a friend hand crank the engine while you lie under the engine pan. Use a stethoscope or shortened broom handle in your ear and place the other end against the side of the oil pan. As the engine is hand-cranked over by your accomplice, you should hear at least one connecting rod striking the oil dipper tray. The reason the sound may have seemed to come from the transmission is that such a noise is "telegraphed" through the crankshaft to the transmission.
So, this is my 2nd best guess, assuming a connecting rod hasn't lost its shims or a piston has broken. You should be able to isolate those conditions by shorting out each cylinder one at a time as the engine is running. If the noise stops or lessens, that's the cylinder where the problem is. Check this out, too.
By the way, when you order new pan gaskets, do yourself a favor and order the little oil pump retaining gizmo. It will make life easier for you and only costs a couple bucks. Well worth the money in saved frustration.
Marshall
 
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I was planning on dropping the pan soon to change the gasket but the oil leak seems to have almost stopped on it's own.
Leaks very little now as the oil level has dropped to 1/4" below "F" on the dipstick.
 
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I'd start by fishing around the bellhousing with a magnet to see if you can pull up any loose hardware.

You are pretty close to Mitch, so is it possible to drive the car to Mitch's shop?
 
If a rod was hitting the pan in the pan, wouldn't that be apparent when the engine is cranked by hand, or with the starter?
 
When using a stethoscope, noises that transmit can be localized better by removing the probe & just use the open hose. Don't touch the engine, just hold it close. You can even localize one ticking valve, by using it this way, along the side cover. MANY times, a simple tool, such as a stethoscope or a test light, can be your BEST FRIEND, along with your DOG, for moral support.
Bill W. (P.S, the stethoscope, with the open hose is a SURE FIRE way to find VACUUM & EXHAUST leaks, QUICKLY!)
 
It was also suggested to me that I start the car with the starter out if the car. I guess I'll try that too. can't hurt.
 
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"700rpm" -
Yes, a starter could also be used instead of the recommended hand-cranking method, but one doesn't have much control over the speed with which the engine turns over when depressing the starter rod. Hand-cranking allows slower revolutions so that the noise can be isolated to a certain cylinder. A starter motor may also mask the sound by its own generated noise. The striking of the connecting rod against a dislodged dipper tray will be much less noticeable if the engine is not running. However, as loud as the knocking sounds on the video, maybe "vespaholic" will still be able to isolate the sound as coming from a connecting rod-to-dipper tray contact using the starter or while engine is running. It's worth a try. If the noise cannot be isolated by using the starter or while the engine is running, one could still resort to hand-cranking, which is what I'd do first anyway. All other variables are thus removed.
Marshall
 
if your using a generator take the fan belt off or leave the battery cable connected to the starter switch or youll blow the genny

if you plan to run it without the starter
 
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I was just going to unbolt the starer and let it sit there on top of the steering column and not disconnect any wires at all, including not disconnecting the battery
Is that wise / safe?
 
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