Accucraft 3-cylinder Shay safety valve fail......................

If I remember right, I have a 3 cylinder too, if you undo the 4 small bolts holding the "steam pipe" to the dome that should allow you to withdraw the pipe and release the dome or uncover a set screw that will release it. That's why the dome can rotate - there is something in there (that pipe or set screw) that fits into a relief cast/machined into the dome's base on the boiler. Max
 
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Those of us who shoot older-style rifles and muskets have another saying, which won't have much resonance over here in UK, but will certainly ring bells over in the USA.

'As clean as a militiamans target.'
 
tac foley said:
Those of us who shoot older-style rifles and muskets have another saying, which won't have much resonance over here in UK, but will certainly ring bells over in the USA.

'As clean as a militiamans target.'
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Gotcha ;)
 
tac foley said:
Nope. that was the very first thing I did and looked for. It's as blank as an idiot's smile. :(
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I forgot. It's threaded. Remove steam pipe, as suggested, lift dome and rotate anti clockwise so it's threaded base engages with those in the boiler saddle mount. Process of elimination (and why was the paint scuffed on those little bolts holding on the steam pipe on mine ?) May you now have many more years of enjoyment from your beloved Shay. Max

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Thanks for the pic, Max. Now, when I can manage to get the darn thing off, I'll know what I'm looking at. Right now, as of half an hour ago, heating up using a heat gun, heating up using the heat from firing it up, and careful use of a home-made strap wrench, courtesy of the advice posted here and on MLS, have ALL failed to budge it even a gazillionth of an inch.
 
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With metal that thick, and the amount of "engagement" being able to heat the saddle part without heating the dome part would be difficult.

Note, you do not want to heat the dome, quite the opposite, an ice cube on the dome is what you want, you want the dome cooler, and the saddle hotter..

Greg
 
Greg Elmassian said:
With metal that thick, and the amount of "engagement" being able to heat the saddle part without heating the dome part would be difficult.

Note, you do not want to heat the dome, quite the opposite, an ice cube on the dome is what you want, you want the dome cooler, and the saddle hotter..

Greg
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With the dome having an internal thread, you could be correct.
 
No special treatment required, heat or otherwise. Just make sure you hold the dome up when you turn so its threads engage with those on the saddle. Max
 
maxi-model said:
No special treatment required, heat or otherwise. Just make sure you hold the dome up when you turn so its threads engage with those on the saddle. Max
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I wish..........................................sigh....................................................................................
 
'Kay. Here is where we are at -

I've taken the cab off - this involves - first -

1. Removing the gas tank - a rpita.

2. Removing the lubricator fine-feed.

2. Removing all the handrails and piping.

4. Undoing a bunch of screws and bolts and wriggling the cab around the permanent fittings. This gave me a better angle to apply the strap wrench, the dome having been filled overnight with penetrating oil.

Nothing.

I'm now at my wit's end - in my case, and already short journey. And wondering if the next step might involve filing a couple of flats on the dome so that I can apply a large vise-grip, but given that I've heard zero back from Accucraft in US on this problem, I'm loathe to make permanent alterations to a loco that has no back-up by way of parts...

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