Freeing off regulator

[Michael CallaghanParticipant @michaelcallaghan68621]

Hi, I purchased a locomotive at auction. It’s not been used for a bit by the looks of the it. The regulator is stuck in position. It’s the butch locomotive. I am thinking applying some heat to the regulator at the blackhead. Or would it be better to put some heat into the grate. I don’t really want to start taking things apart if I don’t need to. Any ideas out there to fix this problem.

[Andrew TinsleyParticipant @andrewtinsley63637]

If it were my loco, I would most certainly dismantle it sufficiently to find the cause of the “sticking”. You don’t have any idea as to what the trouble is, especially as you don’t have any experience of the loco.. Could be nothing or could be serious. You just don’t know.

Andrew.

[BazyleParticipant @bazyle]

Mine (Pansy) only comes loose when hot but I know that it does that and there is nothing wrong. Depends on what type it is, screw down, rotary or slide whether it is reasonable for it to be tight. Would be a good idea to look at the drawings or see if someone on here has one and knows its foibles.

[Brian Baker 2Participant @brianbaker2]

Greetings Michael, regulators of the screw down type always seem to jamb as they cool, to do with differential expansion of the metals used.

Other types are less likely to jamb but may do so with a fault.

Best thing to do is get hold of a set of drawings for the loco, which will always be useful and you will give you a starting point.

Seek advice at your loco club boiler inspector.

Regards

Brian B

[norm nortonParticipant @normnorton75434]

If it is a Butch as originally designed then the slide regulator is inside the dome. Take off the decorative cover, then you can simply remove the pressure dome by undoing the ring of nuts (or might be bolts into the boiler bush). The stuck portion might be a part of the mechanism of the slide, or it could be the shaft as it passes through the backhead gland.

[WearyParticipant @weary]

Maybe worth asking your question on Model Engineering Clearing House forum.

There are a number of active Butch (and Chub, the 0-4-0T version) builders and owners on there.

Regards,

Phil

[Nigel Graham 2Participant @nigelgraham2]

One of the first tips – well more than that, advice – I was given was never operate a regulator dry.

If the valve itself is stiff on its seat, perhaps due to scale, moving it dry can easily score either or both sealing surfaces, making it leaky.

The only safe way here is as Norm suggests: open it up and investigate both the valve and the backhead gland.

[noel shelleyParticipant @noelshelley55608]

I had the same trouble when I bought my BUTCH, it had been unused for many yaers, it was as the rod goes through the backhead ! VERY careful movement and wd40 type oil freed it off and all was well. I have a full set of drawings Etc. Get back to me if I can help, where are you ? Noel.

[Michael CallaghanParticipant @michaelcallaghan68621]

Hi Noel, I am in Somerset. As I write this the regulator is having a WD40 bath. I having a bit of a problem with the hand water pump. No water is getting to the pump or so it looks. I hate taking everything apart but feel it must be a stuck valve in-line someplace. Am I correct however in thinking that the water is free flowing to the handpump and from there to the none return valve on the lower left hand side of the firebox as you look at it. And that water flows into the pump on its lowest connection and flows out at the top. Thanks.

[Nigel Graham 2Participant @nigelgraham2]

“Free flowing”: Not quite correct.

It should flow freely but as the pump dictates.

There are normally two non-return valves in the pump itself as well as that on the boiler. These are usually simple ball-valves.

I don’t know the particular locomotive so the hand-pump may be external, but it is common practice to mount the pump submerged inside the tank, largely to hide a very un-prototypical lump!

Hence the pump is usually the shape of a letter T on its side, with the cross-bar vertical and holding the two ball-valves, and the lower one is normally the inlet as it is only just above the tank floor. You can see what’s what by just seeing where the pipes lead.

No water reaching the pump at all:

There ought be, but often isn’t, a fine-mesh strainer on the inlet of the pipe to the pump, or the inlet of a submerged pump; or inside the tank’s filler. That prevents dirt entering the pump and valves but can itself be choked by sediment or scale. This should be easy to clean, though you may need remove it: examining a lot of miniature locomotives suggests this is a point often missed by the designers!

If the pump is external to the tank, loosen the connection to the pump to see if the pipe to that point is clear or blocked.

.

Water reaching the pump cylinder but not going anywhere else:

1) The pump’s suction valve is sticking open;

2) The pump’s delivery valve is not closing on the suction stroke. Does water emerge if you loosen the union on the clack valve and try using the pump?

3) Neither valve is operating properly;

so although water reaches the pump, it is only being shuttled back and forth.

You may be able to detect that by putting just enough water in the tank to cover the pump inlet, and watching what it does when carefully working the pump without shaking the locomotive.

With a submerged pump (so you don’t really notice the leak) water might be leaking past the ram, but it would have to be a hefty leak to make much difference.

 

[noel shelleyParticipant @noelshelley55608]

Hi Michael, On mine the hand pump is in the left side tank, draws water in from the left tank via a non return – this can stick, a few sharp taps with a blunt instrument on the pump body may free it, if not then stripping the pump it will have to be. Then the water delivers through a second non return, a pipe then takes the water to the front of the boiler, a clack. Depending on how yours is piped this may feed the clack at the rear of the boiler. I have 3 boiler feed methods, hand pump,double acting axle pump and an injector. There seem to be numerous ways people have built this model to incorporate their own ideas. One thing to watch is the piping of the axle pump, mine is fed from the right side tank but returns to the left side tank. This is fine if the balance pipe is clear, mine was joined by rubber pipe that was causing a restriction that resulted in the left tank overflowing. this was solved by making a balance pipe of 8mm pipe and elbows.

Mine has many deviations from the drawings but works very well. Good luck. Noel.

[Michael CallaghanParticipant @michaelcallaghan68621]

Ok, just an update. I took the hand pump out to check. All ok. So this lead to my thinking it was the boiler feed clack valve. However to take that valve apart I also needed to remove the gauge glass and like most things the job gets bigger. However having removed the fittings and having a look at the clack valve it was easy to spot the problem. Lime scale build up almost closing the valve the ball stuck in position. As I write this all the components are in the ultra sound bath. So this could also be the problem with the stuck regulator, ie lime scale. Any ideas of how to deal with that. Thanks

[Nigel Graham 2Participant @nigelgraham2]

Ultrasound might remove some scale but is really for loose particles, and in conjunction with a suitable detergent, lightly greasy contamination.

Vert careful use of mild acid such as citric, or the compounds sold for removing scale from chromed domestic fittings, is about the only thing that will remove lime scale.

For that, brush it on the regulator in-situ, wash it off with water (soft, e.g rainwater if your tap-water is hard). The worst scale on a slide-valve regulator is most likely around valve itself and the link mechanism, rather than the seating. If it is badly scaled up, I’d wonder if the locomotive often primed in the previous owner’s use.

While you have the fittings off and the dome open, it would be worth examining the boiler as far as is visible, for scaling. Kettle descaler should clear it without harm. A simple though not fully infallible test for clear water spaces around the firebox is to open, or remove, the blow-down valve(s), pour a small amount of water into the top and see if it obligingly pours out of the blow-down fitting.

It’s worth giving the boiler a good washing-out at this stage anyway.

…..

I take it you know if you intend running the loco in public, including private club-track service, it will need a boiler certificate, so you will need provide a suitable adaptor to allow the club’s test-pump to connect to the boiler. Ideally such documents should have come with the engine, but the standard test code does allow for their lack by treating the boiler as if it is “new”.

You won’t need this if you only ever run it on your own garden track, but it’s still very wise to ensure it passes the hydraulic and steam tests “by the book”, for your own safety.

If you have it tested by a club (of which you need be a member, of course) it is good practice to give it the normal test, just to working-pressure, beforehand, to ensure it actually can be tested. Club boiler-admirers can, but would rather not need to, refuse to test a boiler that may well be perfectly sound but whose fittings leak like sieves for the want of simple maintenance and preparation… (Yes, I’ve known it happen.)

[noel shelleyParticipant @noelshelley55608]

Nigel has covered a lot of ground ! With a few blanking plugs and all things being equal it is possible to conduct a simple pressure test using the hand pump, this will show up any leaks on the boiler. The design WP was 80psi but 40 or 50 will do for test to start with.

Try loosening the packing gland on the backhead bush to free the regulator, DO NOT use oil inside the boiler.

It would be wise to join a club, there are several round you. For a proper boiler certificate some dismantling will be needed but you will at the end of the job know you have a safe boiler. You don’t say if you have any paperwork for the model ? Good luck. Noel

[Michael CallaghanParticipant @michaelcallaghan68621]

I am a member of a club, but they are pretty useless at offering any kind of help. Ok, I have removed the dome. Lots of what I can only call toothpaste around the regulator slide, this is the course of it sticking. I have ordered some lime scale remover. The fittings I took off the blackhead and placed in the ultra sound had been painted and had lots of dirt on them. So it was ultra sound, paint stripper, wash and into a mix of lemon and vinegar to descale.
I just think that most of what I am seeing is general lack of use, and being used in a hard water area.
washing out the boiler is on the cards tomorrow if it all turns up, which may not happen as the local post office sorting office as no staff remaining.

[Nigel Graham 2Participant @nigelgraham2]

I’m a bit surprised you’ve had to order the lime-scale remover rather than buy it locally. I guess you live in a soft-water area… which I don’t!

I’m sorry to read about the lack of help from your club. That is not good.

…..

By the way I in a somewhat similar situation, overhauling for return to service a locomotive that has been standing forlornly waiting for my attentions for some years now while I try to complete other projects.

My first problem was how to move it about. That’s more or less sorted for now.

Today’s offering: new spindles for the two blow-down valves today, from a piece of very nicely free-cutting stainless-steel. The originals looked chomped from stainless-steel studding, and the spanner squares, filed to somewhere-handy, were not very effective.

Using an oddment of pipe as a “handle” I also tried very carefully to move the hand-pump, mounted in one of the side-tanks. Stuck fast – don’t try to force it. I will partially fill the tanks with rain-water and let it soak to see if that does the trick. I need make a new pump handle too, as the original is long lost.

Assessing whether the regulator is stuck will wait until a preliminary hydraulic test has wetted it. (Having drained enough water out first of course, so I don’t flood the superheater and cylinders!)

.

To make the two spindles, I mounted the stock, about nine inches long, through an ER collet, and made one on on each end, in a series of common operations. The 3/8″ x 20 BSF threads were screw-cut almost to completion – insert-tool, low back-gear speed, straight axial feed, 0.005″ maximum bites  –  then finished with a die. I grooved the bar at the parting-off points, but then machined the squares before parting both completed spindles off; transferring the collet and bar together between the lathe and a dividing-head on the mill.

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