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View Full Version : Spitfire replacing stub axle on spitfire



eejay56
12-03-2009, 01:51 PM
I got a new front stub axle and Bentley says to press it in. I took it to the machine shop and with less than 1 ton of pressure the tip squished where the holes for the cotter pin are. Is there a special trick? Was the axle defective? How far should it go in? Does it really need to be pressed?

Andrew Mace
12-03-2009, 01:59 PM
I don't know for sure, but I'd think that, it being a taper fit (as I recall), drawing it in with the proper torque on the (new) Nyloc nut should be just fine?

TOC
12-03-2009, 02:08 PM
Many moons ago......
If I recall, we used a tube (generally machine shop presses have all sorts of stuff laying around them that work) and we pressed down on an old bearing race against the bearing/seal flange at the bottom.

They need to be tight.
How tight?
Don't remember exactly, but if the book says press them, press them.
I wouldn't want a wheel/axle coming loose at speed.
Or, at all, come to think of it.

Never, as in ever, press the end as it will, in fact, crush.....

TR3driver
12-03-2009, 02:21 PM
I don't know for sure, but I'd think that, it being a taper fit (as I recall), drawing it in with the proper torque on the (new) Nyloc nut should be just fine? That's what I did on my TR3A maybe 15 years ago, and it has worked out just fine.

The tip of a stub axle is very weak (all it has to do is keep the nut from turning), so I'm not surprised it crushed. I certainly wouldn't call that "defective".

TOC
12-03-2009, 06:25 PM
If I remember (and I cannot find my Spit manual), the reason for pressing was the shank....when replacing stubs, not too many folks fully disassembled and glass-beaded the socket.
The shank (and this is pure old memory) could hang up on the edges of the socket a bit, and give a false "seat".
I also seem to recall it wasn't much pressure required.
I suppose if you just put it in, tightened the nut, drove it around the block twice (once in each direction), jacked it and re-checked the nut should work.

Memory okay?

Dave

Andrew Mace
12-03-2009, 06:56 PM
Torque specification for the stub axle nut is 55-60 ft./lb., which I would think was enough to draw it in pretty well. Meanwhile, my Workshop Manual (Herald/Spitfire/Vitesse 6) simply says "Fit the stub axle to the vertical link, with the split pin hole in its outer end horizontal. Secure the stub axle with the plain washer and nyloc nut."

UPDATE: My later (MkIV) factory Repair Operations Manual notes that "Refitting" consists of "Reverse instructions 1 and 2, which were for removal and say "1. Remove the vertical link; 2. Press out the stub axle from the vertical link."