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Worn Myford ML7 Cone Pulley

I've got a Myford ML7 Tri-Leva which over the past few months has developed a "knock" and I wonder if anyone can offer some advice.

I recently changed the rather old drive belts as I thought that they may have worn unevenly, but that didn't fix anything. After much prodding, I've come to the conclusion that the cone pulley block is loose and at a certain point in a revolution it jumps from one position to another, so causing a knock when running at speed. There is a grub screw on the centre pulley, but adjusting that doesn't seem to make much difference.

Is this a problem that anyone is familiar with?

My next attempt at fixing this is to remove the pulley block from the shaft and see if it is fixable in any way or whether it needs replacing, however that's not a totally straightforward process as there is a tight bush that needs a puller to remove. So, before I do that, I thought I'd see if there is some wise person out there who has seen this before.

Thanks, John

Reply to
John Palombo
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Also check both the cone pulley and the driven pulley on the countershaft. These have a habit of working loose over the years. You need to back off the grub screw by a bit, feel for the centre of the looseness, then tighten the grubscrew with the pulley in that position. As you get the screw further in, rock the pulley back and forth to ensure that the screw is seated at the lowest point on the shaft flat. If the pulley is a sloppy fit on the shaft due to fretting in the past, it may be worth replacing the lot.

If the cone pulley on the mandrel were loose, it'd be because the pulley had become separated from the bronze gear.

Mark Rand RTFM

Reply to
Mark Rand

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