Displacement lubricator

[John BillardParticipant @johnbillard11913]

I am seeking advice on how to maintain the displacement lubricator on my 5" Manor. I have noticed a small amount of white sediment in the bottom of the sight glass which may also be obstructing the oil flow slightly.

I have also been advised that the water in the sight glass should have a very small amount of of washing up liquid added to make the water "wetter"?

Would appreciate any words of words of wisdom. Thank you in advance.

John Billard

[John BillardParticipant @johnbillard11913]

Basic maintenance

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

Hi John ,

Some full size displacement lubricators had an arrangement of valves so that the tank and part of the pipework could be blasted clean with boiler steam . Easy enough to arrange similar in a model size system .

Some people have suggested strong brine or glycerine based liquids in the sight glass .

A full size engineman once told me that it didn't matter what you put in the sight glass – it always ends up being oily water sooner or later anyway .

I have often thought that if I ever needed a sight glass system I would use a rotameter .

Regards ,

Michael Williams .

[Sub MandrelParticipant @submandrel]

Michael – you have me running for Google again! But wikipedia tells me that a 'rotameter' is the right name for what i'd call a 'pea in a tube' flow gauge

Neil

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

Hi Neil ,

Two types :

Jumping pea . The pea lifts or bobbles up and down when there is flow

Rotating vane – like a poor mans turbine . Spins round slowly when there is flow . Usually very simple – just a bent piece of tin in full size . Very commonly painted black – yellow on alternate vanes and very visible in sight glass . You will see these used in the old type garage petrol pumps with the glass accumulator on top . Very easy to make in small sizes – doesn't usually even need any bearings .

Regards ,

Michael Williams .

[MICHAEL WILLIAMSParticipant @michaelwilliams41215]

There is also something similar used with gasses where a ping pong ball painted with alternate stripes is just levitated in a glass tube by the gas flow . Usually spins round merrilly .

[julian atkinsParticipant @julianatkins58923]

hi john,

i am bemused at the white sediment…cant think what it could be. you will have to remove the sight glass assembly from the pipework, clean out the sight glass, check everything, then re-fill. i have always used glycerine as recommended by the late roy amesbury. i tried to post here a pic of one of mine but cant seem to get it to upload on this post so you will have to look at my album pics.

i have always painted the backs of my sight glasses white humbrol gloss (on the outside of the glass!)

cheers,

julian

[John BillardParticipant @johnbillard11913]

Thanks Julian

Lovely model cab details. The lubricator looks very similar to mine. I have been talking to a pal who drives locos at Didcot. He says that in full size only plain water is used in the sight glasses. But we have problems of scale to deal with? If any one would know Roy would.

Also I think that I have had the oil needle valve open too much. Perhaps it should just be cracked, allowing oil beads to form.

Still learning!

With kind regards

John

[julian atkinsParticipant @julianatkins58923]

hi john,

roy did a considerable amount of experimentation with these gadgets, and i have never had a problem following roy's conclusions ie glycerine. i have made a few sight glasses much smaller than roy's… see his PRESIDENT design in ME.

yes, the valve on the bottom of the sight glass should be cracked open to give about 3 blobs per minute. i dont like the martin evans' design which has far too big a nozzle size on the jet in the sight glass… mine are 76 or 78 number drill, and the valve underneath 10BA with a very sharp needle point. martin evans copied the fred cottam design. the atomising system is completely unnecessary in my experience, though the on/off GWR type GWR quadrant on the regulator is well worth incorporating…actuating a simple plug valve on the delivery to the sight glass on my locos. i did originally try one of roy's PTFE sleeved valves, but a simple plug valve worked much better in my experience.

glad you liked the cab pic … i try my best! the above loco came 3rd in IMLEC in 1995.

cheers,

julian

[John BillardParticipant @johnbillard11913]

Thank you Julian. I am going to wait till my next steaming to see if I can control the little thing better. Being a newly qualified approved driver at the club track I usually find that any problems are driver related rather than the loco which is well-built – not by me I might add.

Just one final question for now. What viscosity oil do you use? (Sold as "heavy" or "light" – I am using the heavy version).

Kind regards

John

[julian atkinsParticipant @julianatkins58923]

hi john,

ive got both types of oil which i use…neither makes any difference to the size of the blobs in the sight glass or the working of the lubricator. the real determining factor is the level of superheat on your loco (eg how effective they are and whether radient superheaters are fitted) and what the cylinders and pistons are made of and if piston valves are fitted and if so what they are made of. Morris's of Shrewsbury will guide you if you give them a 'phone.

cheers,

julian

[John BillardParticipant @johnbillard11913]

Dear Julian

The enginre has radiant superheaters with cast iron piston valve cylinders. Not sure about the pistons – difficult to check! Do you have a particular use for light and heavy oil?

Kind regards

John

[julian atkinsParticipant @julianatkins58923]

hi john,

you need a grade that is suitable for higher superheat if you have radiant superheaters. the 'lighter' stuff ive got is actually a more refined grade… shell valvata i think though its quite an old 5 gallon can and i will need to check what it says on the can! if you go to a preserved railway they have different grades of steam oil for different types of locos… saturated (non-superheated), superheated, and locos working on the mainline at much higher speeds.

there is a certain theory that steam cylinder oil isnt suitable for gunmetal cylinders with bronze slide valves and pistons and soft packing… though i must admit ive always used shell valvata on my locos of this type with no adverse effects.

it is worth checking what grade of oil your club order.

main point though is that none of the different grades have any effect on the working of the sight feed hydrostatic/displacement lubricator.

my late grandpa started his working career with ESSO at one of the big london depots in the 1920's, and even when in his 90's still had an encyclopaedic knowledge of all the different grades of oil supplied to the railway companies at that time, together with subsequent improvements in oil manufacture for the superheat grades.

cheers,

julian

[Sub MandrelParticipant @submandrel]

Very nice pictures Julian. The "man in the street" would struggle to know which is a model.

Neil

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