Lubricator Not Working

[smallbrother]

Did a few hours passenger hauling today with the 7 1/4 Holmside. For reasons unknown she ran much better today, making much more steam than a month ago.

Anyway, after the run I was checking and cleaning and discovered the oil level had not moved in the lubricator. (Standard ratchet jobbie).

Everything on the outside seems to be moving as it should. Any suggestions what to check first?

Many thanks,

Pete.

[andyhigham]

If it is a ball valve type, the valves are probably passing so the oil gets sucked back on the up stroke
If it is an LBSC oscillating type there may be something holding the cylinder off its seat

[smallbrother]

Hi Andy,

Cleaned it out and it is a twin arrangement, 2 cams on a horizontal shaft, rams with springs underneath the cams. The rams move up and down inside what look a bit like nipples, standing up off the base of the lubricator box. The springs sit over the nipples.

It all moves and returns as far as I can see. I have taken the cams off the shaft and the rams push up and down freely on their springs. Seem to be some pin holes at the bases of the nipples - do these feed oil under the rams I wonder?

It was working last run, but no drop in oil level even after a 3 hour run yesterday.

Pete.

[nonort]

For both pumps to fail is very unfortunate. Start with loosening the outlets from the pumps. Try the pumps oil delivered retighten then move to the cylinder end of the delivery and work the pumps until oil issues from this end. Pump at least half a tank of oil to ensure there is no air lock in the pipe work. Check the ratchets are clean a piece of grit in the wrong place will stop them working double check the ratchet springs. Hope this helps.

[cplmickey]

Just a thought Pete - is there a second non-return valve anywhere. The original builder had put one on my Simplex and that caught me out the first time it stuck open. Ian

[smallbrother]

I will get the loco in a better position tomorrow and have a look at the feed situation. I put some lighter oil in and pumped the plungers up and down. Looked to me like little air bubbles came out of the pin-holes.

Makes me wonder if one has been faulty all along and now the second has packed up.

There are 2 separate connections off the base of the lubricator body so a bit weird they would have the same problem but you never know.

Thanks for advice guys.

Pete.

[Cro]

Pete,

A good starting point here would be some photos of the lube and it's workings please.

Adam

[smallbrother]

May 6, 2019 6:07:54 GMT Cro said:

Pete,

A good starting point here would be some photos of the lube and it's workings please.

Adam

You are correct Adam. I have managed to post photos recentlyish but I don't find it easy.

I have a plan to disconnect the pipes where they meet the cylinder steam feeds. I will then see if I can pump light oil through by hand. If that doesn't work I will try some citric acid.

After that I will wrestle with the photos.

Pete.

[Cro]

It doesn't necessarily sound like it needs cleaning, usually only required if the lube has blown back.

My suspicion, depending on how it's made, is that there is no gland on the rams meaning if your cylinder pressure or line pressure is too great it will blow back past the ram. Which could mean two things, blockage in the line or just worn out rams.

Photos would be a big start if you can manage it.

Adam

[smallbrother]

Well I have taken it apart and put it back together. After a while it started pumping regular spurts from both feeder pipes when I cranked it by hand.

I can't see any non-return valves - the pipework is hidden up behind the buffer beam so difficult to be sure but I would be surprised if they are there.

Anyway, I guess I just have to run it again and see if there was some sort of airlock or blockage. The system worked previously so fingers crossed.

Pete.

[nonort]

Sounds like an air lock to me I suspect that at sometime the lubricator has been allowed to empty either during a run or with the engine on its side during maintenance. The air trapped in the pipe work acts like a spring hence the air bubbles returning to the tank. This is why the Warnett lubricator has check valves immediately at the bottom of the ram properly built these lubricators will work from empty whilst in steam.

[flyingfox]

Greetings,
A tip passed on to me was to use an OLD pressure gauge, to check the output pressure.
Do this with caution, since on stroke of a pump will wreck the pressure gauge completely. try to arrange some kind of pressure relief or a bypass system.
Then you will know if the pump is capable of delivering oil at the pressure you need.
I have only one loco fitted with a mechanical lubricator, and its more trouble that the rest all fitted with hydrostatic.
regard
Brian

[smallbrother]

Now it is pumping freely and regularly (by hand) I will leave it until the next run and see what happens. Since it last worked a month ago, the loco was put carefully in storage and the oil was topped up as the box was about 2/3 full. Difficult to imagine what went wrong to cause the 2 rams/lines to malfunction a month later in these circumstances.

I suppose the rams could wear out so their shafts are too thin, or the cams wear down so they don't push the rams far enough? As the system has worked for 30 months since I bought the loco it doesn't strike me that the system itself is the culprit, although there is always room for improvement of course in the right hands (not likely with mine!).

I hope it was just a coincidence that both lines had an airlock for some reason.

Pete.