Stuart beam engine

[kevin largeParticipant @kevinlarge76611]

I've recently acquired a stuart beam engine dont know much about them it's been sat in a garage for a few years I've had it running on compressed air for a while there is a very light tapping that seems to be coming from the eccentric there is a tiny bit of play ?

Also should there be compression at both ends of the cylinder if I open the top drain the engine will carry on running if I open the bottom drain it will stop

Any help appreciated as I am new to live steam

[kevin largeParticipant @kevinlarge76611]

[JasonBModerator @jasonb]

You may be lucky with the eccentric strap if you give the flat mating surfaces a light rum on some fine emery cloth laid on a flat surface, this will tighten the strap up a bit.

You should have equal steam of air going to both sides of the cylinder, sounds like the valve may not be central over the ports or the timing is off.

[Mick B1Participant @mickb1]

I doubt it would run at all if the timing is significantly off – mine wouldn't till I got it spot-on.

It may be that it keeps running because the top drain is blocked with gum from dried oil?

I think there are a lot of places where a beam engine can end up with a knock because geometric accuracy is demanding over the long components. On mine there's a bit on the main beam pivot that probably originated from a slightly out-of-square journal pin – the equipment I had when I built it wasn't as good as what I have now. I keep telling myself I'm gonna fix it some day.

It also runs faster than I'd like, partly because I had to use a smaller flywheel as my old Speed 10 wouldn't swing the one that came with the kit.

Jason's suggestion for the eccentric strap's good – if you get away with that, you've a nice engine.

http://youtu.be/_oZl-tHkOUY

Edited By Mick B1 on 22/10/2019 20:56:36

[kevin largeParticipant @kevinlarge76611]

Hi all ran it up on steam today for first time lots of steam leaks bad one around the glass tube on the boiler what should I do to seal the leaks dont want to break anything

[JasonBModerator @jasonb]

The glass is more than likely sealed with a thin section O ring inside the nut that is at either end of the glass. You may be lucky and get a seal by just tightening these a fraction. If not then they may have perished over time and need replacing, assuming it is a Stuart boiler with their fittings then that would be the best source for spares, measure the glass diameter to see what you need.

[kevin largeParticipant @kevinlarge76611]

Many thanks

[kevin largeParticipant @kevinlarge76611]

Couple more questions

What pressure should the boiler run at

And what should I use to seal the glands on steam chest and cylinder

[JasonBModerator @jasonb]

Without knowing what design the boiler was built to it's hard to say, if commercial it may have the working pressure stamped on one of the end plates. failing that 50psi would have been likely so err on the safe side of that.

Most of the model engineering suppliers will sell graphite yarn which can be used to pack the glands or you can take a few strips of plumbers PTFE tape and twist into a string then use that in the gland.

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