Crompton Parkinson Motor Bearings

[Peter GainParticipant @petergain89847]

Hi,

Can anyone help; my Googling has been in vain!

I require a pair of replacement bearings for a Crompton Parkinson 3/4 hp 1ph 240v 50Hz motor. The item is from a Myford Super 7 c196? Grey. The motor, also painted grey appears to be the original one. The bearings are worn, probably due to lack of lubrication. As the rest of the motor is in good order & is of superior quality to the Tyco replacement version I would like to repair it.

The bearings are Vanwall Products bushes, oddly, the I/D is 17mm, the O/D is .781″ x 1″ long.

Are there any UK companies who can supply the above or similar replacements?

Peter Gain.

[Peter GainParticipant @petergain89847]

[Swarf MakerParticipant @swarfmaker85383]

Try Simply Bearings: website is http://www.simply bearings.co.uk.

 

They have oilite bushes at 16mm ID X 20mm OD X 25mm long so you could turn to suit. Part No AM1620-25 price £3.08 + VAT.

 

No connection with company other than good and fast service.

 

Does mean you may need to re-assemble the motor first of course!

 

Cheers,

 

Fred

[V8EngParticipant @v8eng]

If you have a motor rewinding company in your area it might be worth asking them about spares.

Not dealt  with his type of company for many years, but this was fairly routine stuff to them then.

 

The following may be teaching granny to suck eggs, if so I apologise:-

Is the shaft really good? we saw new bearings fail quickly if this had been missed.

 

 

 

Edited By V8Eng on 22/01/2010 15:51:45

[mgjParticipant @mgj]

Or you could replace with the right size of ball bearing? I searched and couldn’t find anything suitable – exactly the same problem as you. Eventually I went to the chap advertising “Breaking Myfords” in ME classified. 01205 480666, fort the same reason that V8 suggests. The mike told me that the shaft wasn’t actually as good as it looked.  2 days later saw me with a new ballraced motor which was, as advertised a straight bolt in replacement, all pulleys fitted etc no mods.

 

Its a cracking motor, and good service from the people there.(usual disclaimer)

[Peter GainParticipant @petergain89847]

Thanks for your replies. Simply Bearings responded quickly but were understandably sceptical about the mix of metric I/D (17mm) & the Imperial O/D (0.781″). As the motor was made in the days when the UK still had a thriving manufacturing industry these dimensions are rather puzzling. I have checked with 4 different ‘mikes, all agree within tenths.

I’m not sure from which material the original bearings are manufactured, they are a silver colour & have a comparatively large cut-away to line up with the oil way drilled thro’ the casting.

The wear has taken place in the bearing shell, the shaft mikes up at spot on 17mm.

The Myford is up & running with a modern replacement motor but as the original motor is of superior quality & only the bearings need replacing I wish to rebuild it.

I have considered making phosphor bronze bushes but am not sure of controlling the oil supply. There is an oil hole & nicely made spring loaded cap for both bearings & originally the casting was packed adjacent to the bearings with what appears to have been a felt “mash”.

Oilite bushes are not available in this size & I understand that re-machining closes the pores & inhibits the oil.

Comments will be appreciated.

Peter Gain.

 

[CirclipParticipant @circlip]

“Oilites” can be machined but you have to be aware of “Smearing” the surface. Sharp cutting tools will do it OK as long as you don’t allow rubbing. To re-oil the bushes, immerse in heated oil and keep at temperature to allow the bush to re-absorb oil and then allow to cool down while still immersed.

 

  One problem you may find is that the bearings will contract slightly when fitting into the bore of the end caps so a machined bore may be a tight fit if 17mm outside the housing.  Seem to remember machining sizes being shown somewhere, have you tried “Glacier Metals” site???

 

  Regards  Ian.

[mgjParticipant @mgj]

Or remachine/fit a carrier and insert a ball bearing instead.

 

Nachi list a !7mm id self aligning BB, with ODs of 40 and 47 mm

 

There are also standard deep groove ball races with an ID of 17 mm, and ODs of 26, 30, 35, 40,47 and 62mm. Some shielded and some not. Wish I’d looked in my catalogue before! 

 

Many bearing suppliers will grind the outside or inside of bearings to a special size if need be.

 

The other option might be to get a more modern PTFE lined bush, which are pretty good, if there isn’t enough space to machine a bearing housing.

Edited By meyrick griffith-jones on 24/01/2010 19:47:00

Edited By meyrick griffith-jones on 24/01/2010 19:53:32

[chris stephensParticipant @chrisstephens63393]

Has anybody checked to see if a modern needle roller will fit, hopefully without too much modification to the casing.

I think  that the PTFE lined bushes Meyrick refers to are called “DU” bushes. They are a split Steel bush with a PTFE lining, they come flanged and plain. 

If you do find a source of direct replacement bushes, do please post the supplier. I don’t need any now but it would be useful to have a pair as spares against the day that my ones finally think of retiring.

chriStephens

[Eric CoxParticipant @ericcox50497]

A 20mm Dia bearing is 0.767″, 0.006″ bigger, would this press fit into the housing.

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