Here are a couple more Mohawks I scanned from Mr. Vollrath's collection today. I am pretty sure they are both L-2's but welcome corrections. 2909 2475
Ken, I don't know. It looks like one of those "peanut" whistles but it has some pretty big diameter piping running to it. EDIT: I am linking to a blowup photo.
The pipe feeding that "thingee" appears to be coming from the top of the steam chest. Also the "thingee" appears to be a dented tin can with a screw top, like a brake fluid can. Definitely not a tuned resonance chamber like a whistle. I further assume it vents live steam because for safety, it's positioned on top of the boiler next to the stack, one of a steamers hottest locations. Boy, where's Lew when you need him...?
Something would would help lift smoke higher? I know I have seen lighting for the engine crew to see their stack at night if needed. But that is not what we see here.
How about from the air pumps on the 2909. This is a B4 loco.Flags and class lights. Put 29 as the first # in photo #2 and you have an NYC loco. Most NYC L2s did not have class lights but this photo was before the 1937 book of rules and the numbers change in 1936. It's good to be back. LEW
And it's good to have you back, LEW. Welcome Home. Now, what is the function of that "thingie" behind the stack on 2909?
LEW, glad to see you back here again. I second Hytec's question. We can't figure out what that device is behind the stack on 2909.
I said air pump, but I think it is the exhaust for the booster engine. When I started in 1950 most of the booster engines had been taken off but some of the piping was still there.Will check and see what I come up with. LEW
That seems reasonable. Though I wonder why would the booster exhaust pipe be run the length of the boiler to the stack, which I think would create a lot of back pressure.
Would the steam and exhaust blowing out the main stack right next to it cause a venturi effect and create suction instead of back pressure?
On the NYC ,most ,of the booster exhaust were next to the stack.You wanted to keep all of that steam up out of the way. Now with the pipe in the photos these come from the stoker engines. Again to keep the steam away . The soker engines were under the cab on the fireman's side.The stoker was in the tender behind the coal bin,see the little door on the fireman's side on the L-3,4. The exhaust for the booster was about 4 in. in dia. What the little can was for ???. LEW
Thanks, Lew, stoker engine exhaust makes more sense than booster engine exhaust. I was wondering if the higher volume of booster engine exhaust could be handled by just a four inch pipe. After the suggestion of booster engine exhaust earlier in this topic, I was able to locate some booster engine engineering sketches online. They seemed to indicate that the booster exhaust pipe was much larger than four inches, and that its outlet was inside the smoke box merged with the steam chest exhaust assisting with firebox draft. Draft assistance also makes sense because a hotter fire would be needed to meet the higher steam demand when the booster was operating.
As I said ,never fired an engine with a booster. They removed the boosters from 1948-50.When I first started an engineer asked if I had been on an engine with a booster working.The engine we were on had all of the booster equipment. He said watch ,and when he flipped the valve nothing happened. They had taken the starter valve out but the rest of the booster was in place. That ended that lesson. I to have been checking. Now this is on NYC engines and just means I think this is the way it works. On the H-5,hand fired,the left side ,firemans side is the ,in bound, side. You will notice the supply pipe starts at the top valve casting and goes back to the booster engine.On the right side ,this is the exhaust side,you can trace the pipe almost to the cylinder casting and then what. On the H-5 there isn't any visible pipe near the stack. I believe the exhaust pipe in this case is connected to the cylinder casting on the exhaust passage of the casting. On other locomotives the exhaust pipe comes out from under the boiler just behind the cylinder casting follows around the boiler to the stack. On L-2,3,4 and J1,2,3 with coffin feed water heaters you can see the pipe come from under the boiler and go under the sheet metal covering aroud the coffin feed water heater. On the B&A the booster stack is rectangular on most of their engines . The small pipe is from the stoker. LEW
In a hurry again. The L-4 did not have a booster. I believe 15 L-3b starting with the 3025 or 3026 had boosters. LEW
So that is what I was seeing? I'd forgotten such a device could be installed that way. Were they noisy? If so, could that "can" have been a small muffler?
Muffler that far forward? Thanks LEW for the explanation. It is amazing how many different paths the plumbing took on different locomotives. Still have not seen another with that "can" on it in that location.
The can was on the exhaust pipe for the stoker. I have photos of H-6 with the can . I like do not know its purpose. Many locos ,NYC, did not have these cans on the stoker exhaust. No the noise was not a factor. LEW
