Reluctant Steam Side of Duplex Pump

[Mfoxchicago]

Hey Guys, I've been futzing around with this darn Gardner-Denver Duplex Steam pump for the past 3 months. I've been able to get it to pump (only one side) manually actuated. I use this procedure to pump up the boiler at the beginning of a day of steaming. However, I've not yet been able to get the Steam side of the pump to properly and reliably service my needs under just steam pressure.

The two pistons will move, but only VERY slowly, as if stuck by trying and only if after a great deal of pressure has been supplied. I can see the packing gland nuts on the piston shafts need cleaning up and re-tightening. But knowing this pump has been over fed cylinder oil for years, due to a cracked sight glass on the oil lubricator, permitting much to much oil being fed through the drip line. And a slight suspicion that this pump was not used hardly at all in a number of years prior to my ownership.

A) Is it reasonable for me to suspect the heavy, viscous old cylinder oil that has made its way in to the pump's steam chest, but never headed up or worked through is actually gumming up the action of the pump?

B) I am planning on opening up the steam chest to investigate what might be the internal issues. How should I go about cracking the old gasket open in such a way as to save it or having enough intact to serve as a templet for making a new one?

Thanks for the help!
Mack

[cyberbadger]

Often steam pumps can have poor performance because the shafts are not true anymore. Causes a lot of binding and wear.
Hence the need for excessive oiling, maybe.

Whether simplex or duplex pump, ones that really survive are the ones with some sort of brass liners/sleeves for the water and steam side pistons.

There were tens of thousands, if not hundreds of thousands of these kinds of pumps made for pumping all sorts of stuff. Most of the ones without liners were basically just cast iron and sold as scrap. You can see them around and they aren't worth buying.

I have a Marsh Simplex that I'm almost done restoring - worked under air, but sticky - Made a new shaft. And a Worthington Duplex - sticky but worked under steam.

My Answer to A:
Maybe, especially since there are hidden passages in steam pump castings, the oil could have just gummed them up. Or bits of cast iron rust.

My Answer to B:
You can make your own template from the two metal parts. Don't be shy about it. It's just an old steam pump that needs some TLC.

Pictures would be great, especially so others can point you to literature about your pump or something close to your pump...

-CB

[Mike Rometer]

If it hasn't been used for a significant time then I see no harm in washing it through with paraffin (kerosene) or white spirit, and working it as much as possible to get rid of any residual, dried up, lube. If you wish to open it up, then new gaskets can be made in the same time-honoured manner that all us apprentices had to endure. A sheet of gasket paper and a small hammer, and if you're lucky, enough room (and thin enough paper) for a pair of scissors for the longer cuts.

[DetroiTug]

Hey Guys, I've been futzing around with this darn Gardner-Denver Duplex Steam pump for the past 3 months. I've been able to get it to pump (only one side) manually actuated. I use this procedure to pump up the boiler at the beginning of a day of steaming. However, I've not yet been able to get the Steam side of the pump to properly and reliably service my needs under just steam pressure.

The two pistons will move, but only VERY slowly, as if stuck by trying and only if after a great deal of pressure has been supplied. I can see the packing gland nuts on the piston shafts need cleaning up and re-tightening. But knowing this pump has been over fed cylinder oil for years, due to a cracked sight glass on the oil lubricator, permitting much to much oil being fed through the drip line. And a slight suspicion that this pump was not used hardly at all in a number of years prior to my ownership.

A) Is it reasonable for me to suspect the heavy, viscous old cylinder oil that has made its way in to the pump's steam chest, but never headed up or worked through is actually gumming up the action of the pump?

B) I am planning on opening up the steam chest to investigate what might be the internal issues. How should I go about cracking the old gasket open in such a way as to save it or having enough intact to serve as a templet for making a new one?

Thanks for the help!
Mack

This is one of those cases where nothing is really known until it is dismantled. If the pump rods move easily enough they can be worked by hand then it takes a lot of steam to move them, the rings are probably shot. These pumps get used a lot when used as a primary feed pump. I doubt oil is stopping it up. If that pump is like most of them, there is a shuttle valve operated by steam pressure and they can stick quite easily and often do. But one of the steam pistons should move one direction or the other with force relative to the steam pressure, if not it probably needs new piston sealing whatever that is.

Typically, the valve linkage that can be seen on the pump actually controls the shuttle, the shuttle in turn controls steam admission in to the steam cylinder.

A) Anything is possible, but this is not likely. Over oiling is probably evidence that the previous operator was having difficulty keeping it going because the piston seals are bad. Modern oils can be displaced by water, they are not near as good at prohibiting rust as real steam cylinder oils with tallow are. Tallow is a natural rust inhibitor.

B) Making gaskets is part of the steam hobby, you'll get good at it As Mike points out above, lay gasket material over part then with a small ballpeen hammer, lightly tap the edges for the inside/outside shape etc. For small holes I use a small drillbit in a dremel tool. For large holes buy or make some gasket punches. Don't want to make that gasket again? On reassembly wipe one side with anti seize compound sold at auto part stores. Use it on every reassembly job, gaskets, threads etc. MtnMan on the forum here suggested that and it is great advice.

Remedy is going to be just pull the pump, get it on the bench and clean/repair it.

Seen the pics of your boat, she's beautiful.

-Ron

[barts]

On the gasket side of things, I've had excellent luck using high temperature RTV on steam surfaces that are quite flat.
If I need a gasket for clearance reasons, or if the surfaces aren't flat enough, I use Garlock Blue-Gard.

Gasket punches are available cheaply from Harbor freight, or you can use a piece of steel or stainless
tubing with a sharpened edge. You should use a soft piece of wood as a backstop; end grain is best.

- Bart

[Mfoxchicago]

Hey Guys, so I took your collective advice and got inside that duplex steam pump of mine and got very well acquainted with her workings. It was a very empowering experience. I was so hesitant that I would screw something up, but later found that this pump was just a basic cast iron and bronze machine with operates on some very basic principles - something even my limited experience could wrap itself around.

As I suspected, the steam chest slide rods were indeed gummed up with years of residual steam cylinder oil that were causing them to have transit through the smaller packing gland nuts very erratically; which made the pumping action slow or non-existent. Added to the fact that one of the two pumping cylinders was not drawing ANY water and would slam its was through a stroke when the steam side was actually able to move the piston. Opening up the head of the pumping side, I found all four of the bronze check valve spindles (for lack of a better word) that admitted water and checked its downstream flow, on the non-pumping side, were actually stuck in the closed position by years of too much boiler feed water additive & cylinder oil gunk sticking them to their seat. I removed the springs, cleaned the check spindles and their seats and they began admitting water perfectly. Man I love getting inside a steam engine and its associated systems - you learn SO MUCH.

Through this entire process, I only had one gasket tear as a result of prying the mated parts apart. Tonight, I am making a new gasket. I purchased at a local national auto parts dealer some gasket material. The tech said what my old gaskets looked like was a type of rubber cellulose type material (had sort of a green, turquoise hue to it). The material is made by Fel-Pro Gasket, Part #3075 indicating uses for: Water Pumps, water inlets, bypasses and water outlet (thermostats). Plus I got some gasket sealant to lube the gasket up with as I reinstall the parts.

My question to the "Collective Knowledge" is - am I using an appropriate gasket material for my pumping side of my duplex?

Please chime in and let me know if I'm headed in the wrong direction. This pump is at least 31 years old and what a workhorse it hopefully will continue to be. Thanks guys.

[cyberbadger]

Fel-Pro Gasket #3075 looks just fine.

My opinion of Gaskets for steam stuff is there are many products and ways to do it, and as long as it sealing it's doing it's job. I can't really think of how any product/method could cause any permanent damage to a steam pump. (I may be wrong)

The worst thing that could happen are from bits of it flaking off and clogging passages in the pump. But then you just do a little mini overhaul and take it apart and clean it and put new gaskets on.

For reference I'm using Garlock BLUE-GARD 3200 for all gaskets in my simplex pump I'm restoring. I think it's over kill.
http://www.garlock.com/en/product/blue-gard-style-3200

-CB

[Mfoxchicago]

Thanks CB, yeh, I picked up a tube of VersaChem Silicone Gasket Maker as a final touch of holding the new gasket in place while I put everything back in place. This too may be "over kill" as you say.

Thanks again.

[Mfoxchicago]

I swear working on an old steam boat or its associated support systems, like our Gardner-Denver Duplex Steam pump can be one hell of an empowering rush when you put that old 30+ yr old pump back together, install a couple of new packing glans on the steam chest slide valve rods, build up about 85 lbs of steam and open the inlet valves and SHE WORKS! Too boot, both her pumping cylinders were pumping strong and moving water exactly where she was supposed to. It was a good day on TULE this afternoon.

I still have some tweaking of timing to figure out and there are a couple of additional packing glans that need replacing that looked ok before, but that is easy quick stuff. She ran fairly smooth, reliably and kept going even when the pressure dropped as low as 45 lbs. I am confident when there is a full head of steam up, it will only take a slight crack of the inlet valve to get things moving quite well.'

This weekend's steam and the opening of the business next week will be significantly less stress for me and much easier on my Fireman now that we don't have to rely solely on the Pemberty Injector to supply the boiler when she needs water. Finally, we can start using the Steam pump to move Hot Well water back into the boiler and vastly improve our fuel consumption.

I am a happy Captain tonight!

Thanks guys for all your help and support, especially those of you that simply told me "not to be afraid' of opening that ol'pump up and see what was not right inside.

I finally got myself a working pump! THANKS!!!

[Mfoxchicago]

Good evening guys, Mack here. I haven't posted since back in August and mostly because everything has been steaming along fine for our first season on Lake Nasworthy. Our Gardner-Denver Duplex pump as been working rather reliably until last week. We're going along fine then we tried to pump and it seemed that one of the steam cylinders just did not want to cycle over. With the whole system cold and manually barring it back and forth it moves freely and smooth. But put things under pressure, it will come to dead center to one end, but won't go back in the other direction. I am somewhat at a loss to what is out of whack. We'd recently injected what turned out to be a bit too much steam cylinder oil into the system, which does make some of its way to the GD's steam chest. I thought perhaps it had gummed up the slides and were preventing them from sliding properly, but I opened the steam chest and cleaned the slide facings with B12 Carburetor cleaner and they were sliding fine. So what else could it be....??????

Either I have:
1) some sort of blockage in the exhaust port tube that is preventing the pressure from exiting the cylinder chamber or
2) some aspect of the piston head or its ring(if it has one) has failed allowing for the pressure to build up on both sides of the cylinder preventing proper operation or
3) one of the more experienced, wiser ones here on the forum will have an actual cause for this frustration. Hehe. HELP!

Also, I beginning to ask my self if it might be time to replace this 31+ yr old GD pump for a newer manual/steam driven feed water pump AND if so what recommendations the more experienced captains would recommend. TULE has a Bryan CL-90 / 21 hp Water Tube Boiler, the boiler only holds aprox. 39 gals of water.

If we were to get this feed water pump issue straightened out and off our worry list, we would be pretty much steaming ahead with few if no worries.

Thanks for your help as always.