Scraping noise: Motor? Belt? Bearings? Sheaves? Lubrication?

[user5013]

About two years ago, I was traded a 1961 Mark V in exchange for fronting six months rent to a newlywed couple (I got his father's Shopsmith. Would have liked to be a fly-on-the-wall for THAT conversation!)

Never cleaned or lubed, it had this intolerable scraping noise when it ran. Also something went "ping", and a rectangular spring-like wire popped out onto the floor.

Well, I fixed all that. The Fan Sheave (#504207) had moved, and was scraping against the Fan Plate (#504206). Easy fix.

However I had to nearly take the entire thing apart, before I found the Retaining Loop (#504187) was missing. [Incidentally, it is also missing from any exploded view drawing available.]

Basically this was like replacing the headlight on a car, by going through the tailpipe. I put everything back together, cleaned, oiled, waxed, graphited, etc. and it has run wonderfully. (I have used it weekends, for about 1 1/2 years.)

Now, the stupid scraping noise has come back. BUT, what brought me to this forum is this:
As soon as I "Remove the drive belt from the motor pulley" (Step 4 Removing the Mark V Motor), the scraping noise GOES AWAY. My previous fix does not apply here -- the Fan Sheave is not rubbing against anything. The motor turns quietly; and I can hand-turn the Quill Spindle (& Control Sheave Assembly) just as silently. Put the belt back -- the scraping noise comes back.

So now what? Where is this noise coming from, and what do I replace/fix?

[beeg]

With the belt back on, can ya isolate the noise? I'd still suspect the fan sheave. Do you have this installed? Item#124 part number 504205 Sheave Spacer? Do you lube the SS about every 10 hours?

[JPG]

Clipboard01.jpg (57.27 KiB) Viewed 4234 times

About two years ago, I was traded a 1961 Mark V in exchange for fronting six months rent to a newlywed couple (I got his father's Shopsmith. Would have liked to be a fly-on-the-wall for THAT conversation!)

Never cleaned or lubed, it had this intolerable scraping noise when it ran. Also something went "ping", and a rectangular spring-like wire popped out onto the floor.

Well, I fixed all that. The Fan Sheave (#504207) had moved, and was scraping against the Fan Plate (#504206). Easy fix.

However I had to nearly take the entire thing apart, before I found the Retaining Loop (#504187) was missing. [Incidentally, it is also missing from any exploded view drawing available.]

Basically this was like replacing the headlight on a car, by going through the tailpipe. I put everything back together, cleaned, oiled, waxed, graphited, etc. and it has run wonderfully. (I have used it weekends, for about 1 1/2 years.)

Now, the stupid scraping noise has come back. BUT, what brought me to this forum is this:
As soon as I "Remove the drive belt from the motor pulley" (Step 4 Removing the Mark V Motor), the scraping noise GOES AWAY. My previous fix does not apply here -- the Fan Sheave is not rubbing against anything. The motor turns quietly; and I can hand-turn the Quill Spindle (& Control Sheave Assembly) just as silently. Put the belt back -- the scraping noise comes back.

So now what? Where is this noise coming from, and what do I replace/fix?

Wonder what "111" is.


What is 504206???? Part of the fan shroud on the end of the motor?

FWIW, a common 'problem' is the spacer behind the fan sheave becomes embedded into the fan sheave hub and the fan sheave scrapes against the end of the motor.

[billmayo]

Part 111 is the Retaining Loop (504187). I use either a steel .020", .030" or .040" flat round 5/8" ID shim againest any Floating Sheave that the sheave spacer has embedded into. I find the sheave spacer lengths are between .380" to .410" so I machine new spacers for a .430" length. I go for at least 1/16" to 1/8" clearance between the fan sheave and the motor plate.

[billmayo]

Part 111 is the Retaining Loop (504187). I use either a steel .020", .030" or .040" flat round 5/8" ID shim againest any Floating Sheave that the sheave spacer has embedded into. I find the sheave spacer lengths are between .380" to .410" so I machine new spacers for a .430" length. I go for at least 1/16" to 1/8" clearance between the fan sheave and the motor plate.

[user5013]

Thank you for all your quick replies.

Yes everything is lubricated. I do the 10 hour maintenance weekly, and lubricate the sheaves monthly.

Yes when I put the belt back on, the noise returns. It seems as if the tension of the belt pushes the fan sheave into the fan shroud.

[Yes #504206 is part of the fan shroud -- sorry about the confusion.]

Is it possible for there to be enough play in the motor shaft, that the fan sheave can move about 1/8" into the motor? Did something get worn down?

>>JPG said:
>>FWIW, a common 'problem' is the spacer behind the fan sheave becomes
>>embedded into the fan sheave hub and the fan sheave scrapes against the
>>end of the motor.

Yes there are metal flecks at the bottom of the housing, indicating something has worn down. What is the "spacer" that JPG mentions, and can I get another one?

I have an older manual, with poorly reproduced exploded drawings. #111 isn't the best representation of the Retaining Loop. A quick pencil sketch is:

Scan 001.jpg (117.22 KiB) Viewed 4177 times

>>billmayo said:
>>I machine new spacers for a .430" length. I go for at least 1/16" to
>>1/8" clearance between the floating sheave and the motor plate.

I don't have the knowledge of how to custom-make such spacer, nor where to put it. Can someone enlighten me?

Thank you again for your help.

[JPG]

Thank you for all your quick replies.

Yes everything is lubricated. I do the 10 hour maintenance weekly, and lubricate the sheaves monthly.

Yes when I put the belt back on, the noise returns. It seems as if the tension of the belt pushes the fan sheave into the fan shroud.

[Yes #504206 is part of the fan shroud -- sorry about the confusion.]

Is it possible for there to be enough play in the motor shaft, that the fan sheave can move about 1/8" into the motor? Did something get worn down?

>>JPG said:
>>FWIW, a common 'problem' is the spacer behind the fan sheave becomes
>>embedded into the fan sheave hub and the fan sheave scrapes against the
>>end of the motor.

Yes there are metal flecks at the bottom of the housing, indicating something has worn down. What is the "spacer" that JPG mentions, and can I get another one?

I have an older manual, with poorly reproduced exploded drawings. #111 isn't the best representation of the Retaining Loop. A quick pencil sketch is:

The attachment Scan 001.jpg is no longer available

>>billmayo said:
>>I machine new spacers for a .430" length. I go for at least 1/16" to
>>1/8" clearance between the floating sheave and the motor plate.

I don't have the knowledge of how to custom-make such spacer, nor where to put it. Can someone enlighten me?

Thank you again for your help.

Ah so! The clip that 'retains' the idler sheave on the shaft.

A pita to remove. Only there to prevent the idler shaft from moving towards the end of the shaft when no belt is pressing it against its stop.

Part of 'our' confusion, is that there are two retaining loops. The hair pin one you just sketched and the more prominent more widely known speed control loop on the end of the control sheave(that be the square shaped one).

As for the sleeve, first determine if you still have one. If so the fix I mentioned or Bill's fix should fix the noise.

So, next step, Remove the orbit launching spring, remove the fan sheave and look fer de sleeve and non-original groove in the sheave hub.

FYI "107"

Clipboard02.jpg (128.6 KiB) Viewed 4149 times

The "sleeve" is:

Clipboard03.jpg (28.28 KiB) Viewed 4149 times

[user5013]

Wow. This forum is the best in the world!

<<Rolling up sleeves>>

Why is it, the more time consuming the repair -- the cheaper the part to be replaced?

Thanks again for all your help!

[JPG]

I doubt you are 'missing' the 'spacer'. A thin something to compensate for the groove in the hub is all you need. My 'guess'.

[user5013]

Absolutely correct. [I've noticed a fair amount of folk that read this thread, so I hope you don't mind me adding a couple pictures.]

The spacer isn't missing, although it is fairly worn down.

Motor Damage.jpg (258.63 KiB) Viewed 4047 times

>>JPG said:
>>. . .look fer de sleeve and non-original groove in
>>the sheave hub.

Wow. If you hadn't told me, I'd have thought the groove was part of the original sheave. It is a perfectly machined groove.

Sheave Damage.jpg (340.47 KiB) Viewed 4047 times

>>billmayo said:
>>I go for at least 1/16" to 1/8" clearance between the
>>floating sheave and the motor plate.

There might be 1/16" clearance on the spacer. But once the spacer fits into the groove on the sheave, there's nothing.

Now all I need is the metal equivalent of an O-ring, to fill up that groove.