BELT DRIVEN VACUUM PUMP ???

[MIDNIGHT RIDER]

I have just dis-assembled a belt-driven vacuum-pump.

One thing I found out that I have never seen mention of in any book or manual, THE PUMP DRIVE HAS AN OIL CHECK/FILL PLUG.


Is there any TECH articles, exploded assembly pictures, parts lists, etc. on these things anywhere ??

They are actually very simple, having only a handful of parts, a drive-shaft, three different kinds of bearings, an eccentric cam, and that is about it.

The shaft on this one has slight roughness in the area of the central needle-bearing and the outer sealed-bearing slips and spins in the bore.

When I knocked it all apart, there is a bearing that consists of an outer shell full of loose needles that the cam rides inside.

The diaphragm operating rod actually rides on this bearing, instead of the cam's surface itself.

What I need to see is just exactly what this bearing/cam assembly should look like when assembled.

The one I have went in a million pieces, without me getting to see just how it all should go together.




Even considering it's minor ailments, the diaphragm will instantly build from 26 to 29 inches Mercury, so all is good there.

Thanks.

 

[MIDNIGHT RIDER]

MORE INFORMATION

The needle-type bearing that the cam-eccentric rides inside has the following stamped around it's perimeter :


TORRINGTON C DDDD DD-56424

O.D.= 1.461 Width= .544

36-count needles : .412 long .107 diameter

..............................................................

Shaft O.D.= .669

...............................................................

Between the cam housing and pulley end is a pressed-in needle-bearing that the shaft rides in, and a staked-in plastic seal that seperates the oil-bath from the outer sealed-bearing.

I have not yet figured how to best get this seal and needle-bearing out without damage.

From the two-thousandths wear on the shaft, this needle-bearing most likely needs replacement.

......................................................................


In the housing end closest to the drive-pulley, there is a pressed-in sealed-bearing.

ENGLAND NSK 6203DU5

(worn??) O.D.= 1.574 .471 wide I.D. = .6685 = .0005 smaller than shaft O.D.

The housing bore I.D.= 1.595 = a difference of .021 larger than the sealed-bearing O.D.

Seeing as the bearing is probably the harder material, the housing must be the worn part; how best to cure this is still up for suggestion.

...................................................................................

Does anyone know what lube is best for these ??

Thanks.

 

[towcat]

iirc the few who have changed out the oil went to a 10/30 synthetic. if you have one that isn't burned up, put in a little of whatever you're running and go from there.

 

[Mr_Roboto]

ENGLAND NSK 6203DU5

(worn??) O.D.= 1.574 .471 wide I.D. = .6685 = .0005 smaller than shaft O.D.

Thanks.

That is a metric bearing. Dimensions are 17x40x12 mm. Assuming that is a double sealed bearing, the actual part number is a 6203DDU.... They use the same seals for single and double sealed bearings. If you are looking to replace, an SKF 6203 2RS is the same (or 6203RS if one seal).

If those dimensions don't jive then you have a special order bearing, which uses seals with their standard part number on them.

That Torrington number is not a standard number. Is it a thin or thick shell bearing?