John, the shaft/hub is on a taper and key - conventional.
Yup I've given the hub and the puller bolt a joly good clout of two.
Done the torque up to 110 this afternoon. Still nothing happening.
And yes, I have undone the nut!
A pal who called in this afternoon suggested that propane heat would not touch the hub whilst the massive puller was in place absorbing the heat.

Location: Bonnie Galloway

Sorry Dave, I am not that clever !
I imagine it would depend on the pitch of thread on the puller.
Suffice to say its a heck of a lot.
Nick

Location: Centre of the Universe

using the calculator on this site:

http://www.engineersedge.com/calculators/torque_calc.htm

your 110 ft lb would represent about 4 tons of force. I assumed a 3/4" diameter forcing bolt to get that answer; the thread -or rather the effective helix angle of the forcing bolt thread would affect the true force, which isn't accounted for on the website, so it's really only a guide at best.

with some taper hubs (i.e. ones where there's a spline rather than a sun wheel on the end of the halfshaft) it's possible to remove the shaft, hub and bearing as a piece and then use a hydraulic press to separate the hub from the shaft. This has taken all 30 tons that my press can muster on Salisbury 4HA hubs, and not much less on the small Triumph/Caterham 7/Ital hub arrangement.

Is there any way that you can cobble up something to use a Portapower ram or even a decent hydraulic bottle jack to replace the forcing bolt if using a press isn't an option -unless the existing forcing bolt is enormous, I'd expect that you'd struggle to get much more than 150 ft lb on it without the risk of stripping the thread.

Location: N W Kent

Thanks for the info there Stuart.
I took the shaft to Tom McKean's in Dumfries this morning.
I couldn't bear to watch, but the hub came with a bang at 16 tons pressure.
No wonder the 110lbs on my borrowed puller didn't make it pop!
Cost £10 cash.
I can't speak highly enough of Tom McKean's. A proper old fashioned motor engineering business.
In the past he's done crank grinding, cylinder boring, surface grinding, hub pulling, valve seat replacement for me. 25 years ago he remetalled some RR conrods for me, but doesn't do that now unfortunately.

Location: Bonnie Galloway

Dave, Thanks for letting us all know the outcome and how you finally overcame the problem. Nice to know the outcome of these things should we ever get anything similar ourselves also nice to know that we were all giving the correct advice but without the right amount of lbs torque or in this case tons

John Mason

Location: Nottinghamshire