Update: Accessory Drive/Distributor

[nyvoyager]

I'm new to all of this so a few questions
yesterday I removed the water pump, distributor and accessory drive thinking the metallic screeching sound was the accessory drive. now I am not sure.

this morning I took the parts out of the car and the dizzy would not spin.
after tapping the shaft (it has some play up and down) I got it to spin again.

The accessory drive has no discernible play in or out, or laterally that I can see and spins freely. is there anything else I should be looking at?

rebuild the distributor?
bad bearing?

[Dave Neptune]

Was it possibly a belt noise? They can make a heck of a screech under load.

Your distributor is probably fine, however I would go ahead and lube the advance weights while it is out.

Dave Neptune

[JOHN COOKSON]

Any chance the noise was coming from the alternator?

TRUE GRIT

[ndutton]

Looking ahead

How is your experience for a start from scratch timing exercise?

[roadnsky]

Continuing down the path Neil is looking to...
Did you by chance mark the orientation of the distributor before you removed it?

[Borrowed Time]

Screeching Noises

I am having a similar situation where I recently pulled and rebuilt a leaking water pump and while I was in there, pulled the distributor, starter and alternator so I could clean it up and paint the rusty beast. When I put it all back together and got it running I am hearing a loud whining sound coming from the water jacket side of the engine. My first thought was that the belt was squealing, and so gave it a squirt of WD40 which didn't work, then tightened it to the point where it is probably too tight and am still hearing this screeching squealing noise that becomes louder (maybe just more noticeable) at lower RPMs.

Does this sound like an accessory drive bearing failure or simply a worn out belt? When I had it apart, the belt looked to be in good condition and the alternator spun freely.

[tenders]

Take off the belt and see what happens. The engine will start and run happily for hours without an alternator if your batteries are reasonably charged up. My bet would be on the accessory drive bearing, though. You went from no sound to full volume all at once? That seems odd for a bearing failure to me, but I haven’t had one myself (yet).

[JOHN COOKSON]

To test the accessory drive bearing push on the pulley with a piece of wood while the noise is happening. Any change in the noise implicates the accessory drive bearing.
Careful around moving machinery.

TRUE GRIT

[joe_db]

I got an accessory drive and then found out the alternator was the cause of the noise
So if anyone needs one I have a spare.

[Borrowed Time]

Thanks for the replies John and tenders. I think I'll take the belt off, run it to confirm no noise then replace belt with a new one. One other factor in the story I neglected to mention is that I scrubbed, wire brushed and degreased the side of the block and washed it down with a fresh water hose, so I wonder if I could have gotten bearings wet or caused rust on the pulley or similar due to a wash down.

Depending on what I find I might be interested in that drive Joe. Are you getting rid of the new one or the one you took off?

[joe_db]

I never took my original off, it is the spare I can send you.

[Borrowed Time]

Hi All,

The update is that the racket continued even after the belt was removed. Before I removed it though I pressed a stick against the belt while running and it made no difference in the noise. So I took the belt off and pressed the stick against the rotating pulley and beside the obvious new grinding noise, didn't seem to make a difference in the whirring.

I figure that eliminates the belt itself, dirty pulleys and and the alternator as the source of the noise. I then removed the distributor and checked the rotation and it is spinning freely with oil on the worm gear when I pulled it out of the accessory drive. If nothing else, I got to practice setting the timing from scratch and it fired right up, course it is still making that noise!

I can't imagine another source of the sound and am 90% certain it is the bearing(s) in the accessory drive.

Is that offer still good Joe? I'd like to take that spare off your hands.

[nyvoyager]

The noise from the original post turned out to be the distributer.
Left it with my kid brother who took it apart and rebuilt it. even powder coated it! Cool kid!

[JOHN COOKSON]

Is the sound present when the engine is out of gear in neutral? Does the nature of the sound vary or change with with RPMs? Is the stuffing box running hot?

TRUE GRIT

[Borrowed Time]

Update: Accessory Drive/Distributor

My boat seems to be making the noise at all RPMs whether in gear or out. I serviced the stuffing box a while back when I replaced the rear main seal and did just check it and it's running cool and dripping as it should.

According to the MMI bulletin I found yesterday on Accessory drives "ACCESSORY DRIVE: Repair and Modification ... these failures usually manifest at low RPM, first by a rattling noise, then a low grinding sound, and in worst cases, a rather loud screech (at any RPM)..." Sounds like my problem, where I am somewhere between grinding sound and loud screech. I think my oil seal behind the pulley probably let a bit of water into the front bearing during my recent cleaning of the block and accelerated the deterioration?

I am curious about Voyager's distributor above, what was the source of the noise in the distributor? I painted mine when I had it apart but since it was spinning freely, did not think to disassemble it, just squirted a few drops of MMO on the weights and stuck it back in there. I am running an Pertronix ignitor in there and heartily endorse the electronic ignition upgrade, but recommend MMI's coil go with it. Pertronix's flame thrower did not last 20 hours on my boat before it gave up and Don's coil has been trouble free for several years now.