Myford Connoisseur Countershaft

[CabengParticipant @cabeng]

[CabengParticipant @cabeng]

As I mentioned on the Myford sale topic, I bought one of Myford’s ‘show’ lathes, the long bed Connoisseur lathe. It had never even had any oil in it’s bearings, slides or gearbox, so it’s effectively a new machine. But there’s a problem with it, something I haven’t come across in 40 years of S7 ownership and usage, so I’m hoping that someone here might have some suggestions. Long description of the problem follows!

 

After oiling everything up I started off by giving it some gentle running in, just letting it run whenever I was in the workshop doing other things, gradually increasing the speed at which it ran, working it up to 2500 rpm over a couple of weeks. It’s not cut metal, it isn’t even bolted down as yet.

 

The machine has developed a very distinct (for distinct, read quite loud, and very annoying!) clattering from the countershaft, originating from the area of the left hand bearing. It sounds as though the balls in a bearing are rattling around, a sound I’m familiar with from my youth, when car alternator front bearings would pack in, identifieable by putting the business end of a screwdriver on the housing, and the left ear to the other end!

 

The sound is only present when the countershaft is turning, i.e. when the clutch is engaged, and it’s affected by belt tension – slacking off the spindle belt can eliminate it, but only by slacking off to such an extent that the belt is very loose.

 

It’s far less noticeable when the machine is running in reverse, it even disappears at times, and when running forward it’s worse with the belt on the left hand section of the pulley.

 

If it’s been running in reverse, and is in nice and quiet mode, switching to forward without touching either the clutch or belt tensioning levers will usually (but not always!) result in it running quietly in the forward direction. But then disengage the clutch and re-engage it and the clattering invariably returns!

 

I suspect it’s the thrust bearing but I’m not even sure that a Connoisseur has one. It must have, but the problem here is that Myford don’t seem to have ever updated the manual, so the only reference I have is the S7 drawing in the manual supplied with the machine. This shows a thrust bearing (99 on Drawing Q), a collar (100) and a circlip (101) – the collar and circlip should be visible between the bearing housing and the left side of the countershaft pulley – and on Ye Olde Greye S7B/PCF machine they are indeed visible.

 

But they’re not present on the Connoisseur countershaft, so something’s been changed, but as I know not what at the moment I’m a bit wary of starting to pull the shaft for examination. So, before I resort to drastic action…

 

1) Has anyone out there come across a clattering countershaft on an S7?

 

2) Did you find out the cause, was it the thrust bearing?

 

3) For anyone else with a Connoisseur, have you experienced a similar problem?

 

4) Has anyone ever dismantled a Connoisseur countershaft, and if so, exactly where do I hit it with a big hammer?!

 

All very annoying and frustrating, so perhaps big hammer, should be changed to BLOODY BIG HAMMER!

 

 

 

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