Stinger Vacuum - Replacing The Top-Bushing Cheap

Stinger Vacuum - Replacing The Top-Bushing Cheap

My two gallons Stinger Vacuum was making a grinding noise from the motor's fan gnawing away at the plastic housing.

Being kind of "handy", instead of throwing it away, I figured that I could fix it with a new bushing and whatever was lying around.

After removing the seven screws and half of the case, I could see that the fan is just pressed on the top of the 1/4" diameter rotor shaft and it came off easy enough.

The motor had plenty of brush material left, but the top-bushing was pretty worn out, (sorry the gap is hard to see in the out-of-focus photo, I just took a few cell-phone pics to show a friend and I had no plans to write a "how to" article).

I removed the grounding screw and wire, and the two screws holding the top-bushing mount (these screws also hold the motor in place).

I forgot to take a "before-photo", so this out-of-focus "after-photo" which I took after reassembling the parts will have to do.

There is a circular clip holding the top-bushing into the underside of the mount. By using a vice with a 5/16" bolt and a socket larger than the clip, I pressed the bushing and circular clip out (the clip broke in the process).

I could not find a "genuine" replacement bushing, so I searched for a bushing that would fit into the mount with little modification.

I found something that I thought would work on eBay for $3.95 plus $3.95 shipping and handling.

"Oilite Flange Bushing Bronze 1/4 id x 3/8 od x 3/8 Brass sleeve bush bearing F20", found at:

http://www.ebay.com/itm/351243232742I received the flange bushing in a few days, and now the fun begins with figuring out how to hold a flange bushing in a mount designed for a different type/shape of bushing, as can be seen in the out-of-focus photo.

I decided to insert the flange bushing from the underside of the mount using two washers to hold it in place.

One is a (5/16", I think) flat-washer to hold the flange bushing in place (the I.D. is larger than the 1/4" rotor shaft and the O.D. fits into an indented area on the bottom of the mount).

And one is a (5/8", I think) star-type lock-washer to hold the flat-washer in the mount.

The star-type lock-washer is slightly concave (or dish-shaped) and when its flattened, the O.D. gets larger, pushing the steel points of the star into the lip on the underside of the cast aluminum mount.

As the photo shows, to flatten the lock-washer I made a "screw-press" using;

A 1/4" bolt about 2 1/2" long (being careful not to scratch the inside of the flange bushing while inserting and removing it),

Two 1/4" washers (one is thicker, no reason, just on hand),

A 7/16" or larger nut as a spacer to keep from damaging the protruding part of the flange bushing while pressing it together (the nut has a larger I.D and it is also taller than the bushings protrusion),

A 1/4" flat washer with an O.D large enough to flatten the lock-washer, but slightly smaller than the underside of the mount,

A 1/4" nut (this one has an attached washer, no reason, just on hand).

The "screw-press" assembled and screwed together about as tight as I could get it.

The screw press forced the flange bushing into the mount very firmly and the points of the lock-washer made good contact with the inner surface of the lip on the bottom of the mount, but I put the "screw-press" back on (without the lower washer) to apply pressure while I gave the lip a few love-taps with a hammer just to make certain that the lock-washer is tightly held.

While installing the bushing mount back onto the motor, I found that there is a little "wriggle-room" or "play" and, because of that, the mount position is not automatically centering the rotor in the stator, so I moved the mount around slightly until the gap between the rotor and stator where pretty-much equal all the way around (I just eyeballed it) before tightening the two screws that hold it in place.

The flange bushing is higher on the rotor shaft than the original bushing, which may be stronger and more stable.

The part of the bushing that is protruding above the mount leaves just enough clearance to install the motor's fan so that it won't rub on the bushing while the vacuum is running.

This photo shows the installed fan with the flare up, but before I "hand-pressed" it back on the rotor shaft, I brought the fan to the vice and pressed a 9/32" socket over the flare to shrink the inside of it a little for a tighter fit on the rotor shaft.

After "hand-pressing" the fan onto the rotor shaft, and adjusting it to spin true, I applied some Locktight for added assurance.

I put the Stinger Vacuum back together and Woo-Hoo!

Better than new for less than $8 too.