Clarification based on info from two historians with more knowledge of former FDNY apparatus than the rest of us:
There were no battleship gray pumpers.
In 1937, a 1921 White/Peter Pirsch city service ladder truck was converted to serve as Smoke Ejector & Foamite Truck 1, and quartered at Engine 31. In 1941 it was moved to Engine 7.
During 1942 a second 1921 White/Peter Pirsch city service ladder was similarly converted, the chemical tank and booster removed, painted gray, and assigned as Smoke Ejector & Foamite 1. The original Smoke Ejector & Foamite 1, painted red, was reassigned as Smoke Ejector & Foamite 2 and moved to Engine 224.
They were later redesignated as Smoke Ejector & Foamite 41 and 42, and were disbanded in 1957.
Five 1924 American LaFrance tillered aerial ladders, four 75-foot, one 85-foot, were converted to become relay hose wagons in 1942. They were designated Relay Hose Wagons 1, 2, 3, 4, and 5. They were also known as Relay Hose Wagons 101, 102, 103, 104, and 105, and were quartered at Engine 7, Ladder 2 (later Engine 19), Engine 208, Ladder 115, and Engine 327 respectively.
All were disbanded on May 15, 1945, one week after VE Day. All five were painted gray. None would have fit into the E-236 firehouse.