730 Gets a Boiler

[PeterCraymer]

My blowdowns have a stainless steel disc with a hole in them that rotates to align with the hole in the body of the valve. The disc seals against a viton o-ring as opposed to the plastic disc/hole that yours has. The o-ring hardens after about a year or so, so i just change the o-ring. The hole in the disc needed to have a nice smooth, polished bevel so that it doesn't pinch and cut the o-ring as the hole passes over it. I believe it was Bob Reedy who showed this design in LSOR articles a few years ago.

[ccvstmr]

Peter, thanks for the comparison.

Can I ask...did you fabricate or purchase your blow down valve(s)? If purchase...from who? Would also ask...do you have any photos to share?

Coming up, will describe efforts to improve the Rutland whistle valve/whistle operation. If there is one item that came out of that experience... a metal on metal seat is not (in my opin) the best way to seal steam. Never had luck tapping a ball into a brass/bronze casting for a sealing surface.

With whistles and other applications (pumps), believe either a stainless ball on a soft seat (O-ring)...OR...a soft ball on a metal seat. A little resiliency is needed somewhere in the arrangement between the two parts. Will explain later. Carl B.

[ccvstmr]

Here's another "quick hit"...

While bringing the Rutland back to life, identified a steam leak in the upper water glass isolation valve. Originally thought the packing nut around the valve stem was loose. Tried to reach in thru the cab windows with a wrench to tighten the packing nut. Seemed the packing nut never got tight. At that point, had no choice but to remove the cab roof (some 30 button head screws) to gain full access to the valve.

Shared the following photo when discussing the plumbing work. Sometime after the photo was taken, the valve handle was replaced. I'll post the photo again for reference...

With the roof off, found the valve bonnet (?) was broken. Was surprised more steam was not blowing out the top of the valve. If you look closely in the next photo, you can see the top of the bonnet broken off inside the packing nut.

As luck would have it (doesn't happen often) had a similar valve in the valve supply box. Removed the bonnet, valve steam, packing nut, etc and installed that on the valve body. So, still had at least one, good working valve. Next photo, should now be able to see the broken piece in the packing glad nut.

For whatever reason, decided to replace the entire valve. Despite spending so much time to seal the pipe threads on this short piece of plumbing...took the plumbing apart AGAIN and installed a new valve. Believe this is a PM Research valve. Used the Permabond thread sealer and had no leaks when reassembled. When completed, had a new valve in place that sealed...and was back in business.

With the new valve in place and all pipe joints sealed...put the cab roof back on and re-installed the (30) button head screws. Problem resolved.

Next time, I'll get into the whistle. Carl B.

[amadlinger]

Hi Carl,

Excellent series you have going here. The Everlast blowdowns you have are from Howard Gorin, The Machinery Works.

Sincerely,
Adam

[Marty_Knox]

Full size we called them Ever Dribble blowdowns. They will seal under pressure, but if you open them when the engine is cold, with no pressure, they dribble.

[ccvstmr]

Adam...good to hear from you. Glad you're enjoying the write up. Thanks for the info about the blow down valves. Tried to look up The Machinery Works to get a web address...didn't find anything. At least I know where the valves originated. Carl B.

[ccvstmr]

Hello Marty...Ever Dribble blow down valves. Good one!

Before receiving some TLC, my blow down valves would "dribble". This was one reason water was never left in the boiler after a run. Feared that dribble would run down on someone storing a loco underneath in the engine house. The better course of action seemed to be blow down at the end of the run. And now...open the boiler (remove safety valves and open blow down valves) to allow whatever air circulation was possible.

Have heard some people store their boilers wet between runs. Word was, after raising steam, all the oxygen would be boiled out of the water. Less oxygen in the water that would cause internal rust. However, if the boiler water level needed to be topped-off...then oxygenated water is being put back into the boiler. Seems that would defeat the purpose of trying to eliminate rust. Just sayin'... Carl B.

[NP317]

To reduce dissolved oxygen in my locomotive's boilers, I keep a valve on top of the steam dome open during fireup.
I let steam out for several minutes, taking the oxygen with it. This replicates a method used by commercial steam plants.
For steady state systems, there is always exhaust steam escaping from the highest point. This is visible on the Seattle steam plant, and the operators explained that function to me during a tour, many years ago.
RussN

[ccvstmr]

Hi Russ...thanx for your post. Before leaving the steaming bay area, the safeties lift at least once. Sometimes both safeties let go. Washed the underside of the steaming bay canopy. However, as soon as additional water is put in the boiler, oxygen is readmitted to the boiler.

Will add before leaving the steaming bays, check all the water feeds: 1) injector, 2) steam powered water pump and 3) the tender hand pump. Once underway, can verify the axle pump works as well. Have to say, there's been times once I'm on the RR, have used the steam powered water pump ONLY for all feed water needs. It's just FUN to listen to that pump plug 'n chug! Carl B.

[NP317]

Carl:
You and I have nearly identical steaming protocols.
Nice to know.
RussN

[ccvstmr]

Ain't Whistlin' Dixie!

Closing in on the end of the boiler replacement project including other loco upgrades. Will look at the whistle and whistle valve now. Might have to make (3) posts to share all the photos. Hopefully, others will find something to use from this.

Before I get into the discussion, would like to point out I have (3) Locoparts whistle valves. #1 and #2 are early vintage Locoparts/Don Orr valves. These were made by modifying a cast check valve body. Other steamers that have these valves no doubt remember the "flow arrow" points in the reverse direction for whistle applications.

When Don Orr sold Locoparts, Jeff Dute picked up the business and released a new silicon bronze cast whistle valve body with redesigned "guts" that eliminated the stainless ball on a hard machined surface...and went with a stainless steel ball on a soft O-ring seat...and a cast-in "flow arrow" in the right direction. Will refer to this valve as #3.

Understand the newest Locoparts whistle valves have been upgraded from the valve I purchased a few years ago. This time, Jeff has incorporated a "poppet" style valve stem against the soft O-ring seat.

For this conversation, will use the #1, #2 and #3 numbers when referring to the various valves. Will start by showing the previous valve and piping arrangement. The piece of Tygon tubing over the valve handle was for heat protection.

Couldn't make the piping arrangement any more convoluted than it was. Almost looked like the opening scene from Monty Python's Flying Circus. If unfamiliar with that...how about the "pipes" computer screen saver! Was pointed out, that similar to electrical resistance in wire, too many twists and turns in the piping will reduce steam flow. The above arrangement had (6) 90 deg elbows, (1) stop/isolation valve and (1) whistle valve. There was also a sweeping 90 deg tubing bend into the whistle mounted below the engineer's side running board (made to look like an air reservoir). End result of all this...reduced flow to the whistle. At least the valve was tucked in tight to the turret, but this was about to change.

The old valve and associate piping was removed along with the original stop/isolation valve on the turret. A 90 deg elbow was left in place and capped off. Fortunately, there was a 1/8 npt pipe plug on the end of the turret. Would use that port for the revised whistle steam feed.

Took the #1 valve home and pulled the #2 valve out of the drawer. Started to find a more suitable piping arrangement and keep whichever valve was ultimately used as close to the turret as possible. The next arrangement put the valve handle too far to the right...and that would end up under the cab roof. Realized too, that the "pull handle" operation was not going to work and would have to go back to a "push handle" configuration.

That wasn't working out. Decided to try another approach and this time use some 45 deg elbows.

Around this time, realized this was insane! One of the problems to resolve was eliminate all the 90 deg and flow path twists and turns. The above (2) arrangements certainly had few-er turns...BUT...the constant piping size changes were just as bad. 1/8" pipe...dropping down to 5/16" tubing...then back to an 1/8" whistle valve fittings...and more of the same on the valve outlet. Not good!

Decided to use as much 1/8 npt pipe and fittings as possible. Back to the store to get some 1/8" 45 deg elbows. This resulted in the following piping arrangement: (1) 90 elbow plus (2) 45 elbows...which was the equivalent of (2) 90's. A big improvement from the original configuration.

Would later try to wrap the piping for insulation to reduce steam flow condensation. Had some work boot shoe laces in the drawer. Nice and thick. Two problems...1) the laces did NOT wrap nicely around the larger brass and cast red brass fittings and 2) the laces added so much diameter to the piping, the Johnson Bar could not be pushed to the full forward position.

Will add, the lacing looked like carp (you rearrange the letters)! Another approach was needed. As many of you know all too well, sometimes have to take 3 steps back to go 4 steps forward. Before getting to the "better" arrangement, will look at the whistle valves next. Carl B.

[ccvstmr]

Still not Whistlin' Dixie...

Recognized some of the improvements on the #3 valve were great improvements and decided to TRY and incorporate those concepts to upgrade the #1 and #2 valves. Here's the #3 valve...an earlier Locoparts/Jeff Dute valve.

These included: 1) longer valve stem and perhaps even more important...a threaded hex cap with O-ring to seal around the valve stem! As previously mentioned, the current Locoparts valves have been further upgraded to replace the stainless ball and brass stem with a stainless steel poppet style valve stem. This eliminates the stainless ball. Supposed to improve steam flow thru the valve.

So, for the #1 and #2 valves, made longer stem guides. Those guides are threaded 1/4-28 to screw into the valve body (as before) and 5/16-27 thread for the cap. An 1/8" id Viton O-ring provides the steam seal inside the cap. Some additional notes....you can see where the original reverse direction flow arrow was removed and the side of the valve marked with the proper flow direction arrow. The valve was numbered...#2.

Around this time, was suggested that a ground, 1/4" diameter seamless Viton ball replace the stainless ball. Okay, NOW...have a soft ball sealing against a hard valve body surface. Would later find...this was a good choice. A stainless seat was machined to sit between the spring and the 1/4" Viton ball. Didn't want the spring end to cut the Viton material. Used a 1/4" ball end mill to "dish" out that seat. Same cutter was used to "dish" the end of the valve stem as well. These should help "cradle" the Viton ball.

Along the way, found the machined sealing bevel inside the #2 valve was cut deeper than the #1 valve. Figured the 1/4" diameter Viton ball was close to getting stuck inside the valve body, decided to use a larger, 3/8" diameter Viton seamless ground ball in the #2 valve. Valve stem and Viton ball seats were "dished" using a 3/8" ball end mill cutter.

Realized too, with the hex cap...would need new valve handles. The "cut-out" for the hex cap and stem would have to be deeper. Also had to make the handle longer to stick our from under the cab roof. Obviously went thru a few variations until the final dimensions were determined.

We're getting close to the end. Many of the elements were falling into place...some easier than others. The #1 and #2 valves had been modified with a stem seal, a soft ball on a hard seat and a handle with better geometry for activation. If there was one thing I'd change...these Viton seamless balls were 70 Durometer. These can be squeezed by hand between two fingers. Am considering trying 90 Durometer Viton balls as well as Silicone seamless ground balls. It's a never ending search for truth, justice and the best working whistle valve possible.

Next time, we'll pull it all together. Carl B.