Disassembling the plungers.
|Bob Johnstone||25/11/2018 12:57:17|
11 forum posts
I've hit another snag in my Super 7 restoration, and wondered if the ME hive mind had any experience or suggestions.
I'm trying to take apart the plungers on the reverse tumbler and back gear levers, as they are both bent and don't 'plunge' freely. The exploded parts list shows the problem part to be H57 (A3021)- plunger, but these are held in by two screwed bushes (H59). Now, I can make the new plungers, if I could only unscrew the collars, which have seized over time (and abuse).
Does anyone have a good idea of how to undo these things? It looks like they've already been beaten on with a screwdriver in their past, and I'm reluctant to do that again for fear of making the damage worse.
Is there a special tool, Myford proprietary or otherwise, that I should be looking for? Or do I have to customise something out of tool steel that I can pound on with the impact driver? Surely the factory had to have something to put them in with in the first place?
Any ideas guys?
2663 forum posts
FWIW... Make up a 'driver' from some MS tubing that is a neat fit over the plunger, with two prongs that fit the bush slots, apply some heat & see if the bush starts to turn, if so then work the bush back & forth to gradually ease the threads until you can unscrew it fully. It could be that with the plungers being bent they are impinging on the ID of the bushes forcing them against the internal thread of the levers, working the bushes loose would show if that is the case & you would have to try & straighten the plungers a little to allow the bushes to rotate around the plunger.
|621 forum posts|
If you take the levers off the machine and remove the knobs, the plungers and springs can be pushed through and a full size screwdriver used to remove the slotted caps. These screw down against a shoulder and are often very tight.
|Bob Johnstone||26/11/2018 16:24:03|
11 forum posts
I'm so glad there are smarter folks than me on this forum. I never thought to try pushing the plungers through. I thought they were captive. Once they were out, removing the collars was a 3 minute job with an ordinary screwdriver. Cheers Daveb!
Now it seems that I've got a bit of a Franken-Myford on my hands, as the plungers and collars are two different shapes and sizes, and aren't interchangeable between the levers, although the exploded parts diagram in the manual shows them as the same parts (and part numbers) in both levers. Makes no never mind, as I intend making my own new plungers to suit.
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