226 6/4/1900 Y 401 1901 K1, Q1
229 29/6/1901 Y 402-11 1902 K1, Q1
231 7/1/1902 Y 412-21 1902-03 K1, Q1
233 28/10/1902 Y 422-40 1903-04 K1, Q1
247 26/1/1906 Y 441-45 1906-07 K1, Q1
259A 27/1/1909 Y 446-50 1909 K1, Q1
259B 27/1/1909 Y 451-55 1909 K1, K2, Q2


No. 401 CLASS

4ft-8in wheels, cyls 19¾in x 26in, Gresley Dgm 2 boiler, LNER Dgm 4 boiler

Boiler dwg N96, later N194
Cylinders dwg M85 (6/1900)
BO 531 was issued (6/4/1900) for one boiler for EO 226 issued the same day, for No. 401.

Nos. 401-50 were built 1901-1909.   The were known as Long Toms.

Fig. 106
No. 401

Originally Ivatt had intended these engines to have 18¾in diameter cylinders, but this was altered to 19¾in.  This left insufficient room between the cylinders for the usual vertically arranged slide valves.  The cylinders were inclined at an angle of 1 in 6.75.  Richardson balanced-slide valves were located horizontally above the cylinders, actuated by a system of rocking shafts by Stephenson link motion, as in the earlier Class 267 4-2-2s, which also had large diameter cylinders.

Cylinders with piston valves dwg M131 (9/1908).

Shortly before Ivatt's retirement Schmidt 18-element superheaters and 8in diameter piston valves were fitted to Nos. 416 (8/1911), 405/20 (9/1911).  Superheating was extended by Gresley, see later.

Cylinders dwg M127 (6/1908) for No. 417 altered.

The coupled wheels of Nos. 401-45 were devoid of balance weights.  Nos. 446 onwards had them and they were also fitted to No. 417 when it was superheated (12/1908). They were also fitted to several other superheated engines in 1911-12, e.g. Nos. 402/42, but there were no further examples.  Surprisingly they were not fitted either to No. 420 when it was rebuilt with a larger boiler in 1914.

No. 451 SERIES

4ft-8in wheels, cyls 21in x 26in, Gresley Dgm 2 boiler, LNER Dgm 4 boiler

BO 589B issued (22/1/1909) for Nos. 451-55,
N194 dwg (3/1909) with superheaters for BO 589B, dwg superseded by N203, see under GRESLEY.
Cylinders dwg M136 (5/1909) for 451-55,
Boiler with superheater dwg N210 (7/1910) for BO 606, [Ivatt issue]

BO 606 issued (23/10/1911) [Gresley order]

Nos. 451-55 were built 1909.

These engines had Schmidt 18-element superheaters and 8in diameter piston valves.  Unusually, Nos. 452/54 kept their original boilers to the end.



Boiler dwg N203 (7/1910) with superheaters for BO 606, [Ivatt issue]
General Plan dwgs P50/51 (26/9/1910) for 420 superheated

Boiler with superheater dwg N207 (11/1910) for BO 606, [Gresley issue}
BO 606 issued (23/10/1911) for 10 boilers with 18-element superheaters.

Three more engines were fitted with superheaters for comparison purposes: Nos. 415 (3/1912, Schmidt-type, retaining its balanced slide valves), 402 (4/1912, Robinson type, with piston valves).  Comparison could now be made between two varieties of superheater and two varieties of steam chest valves.  Nos. 406/07/10 were superheated next (Schmidt-type, and these were the last with their anti-vacuum valves located out of sight close to the cylinders.  In future these were located just behind the chimney, connected to the superheater header. Initially these were the twin "pepper-pot" type, superseded by one "mushroom" type valve, the first one being fitted to No. 445 (August 1913).


Schmidt-type 18-element superheaters were carried by Nos. 403 (5/1913-6/1926), 405 (9/1911-12/1927), 406 (6/1912-1/1928) , 427 (6/1912-11/28), 410 (5/1912-8/1927), 415 (3/1917-1/1927), 416 (8/1911-9/1929), 417 (12/1908-12/1926), 420 (9/1911-2/1914), 421 (10/1915-3/1929), 427 (9/1912-5/1925), 432 (10/1912-2/1929), 440 (7/1913-10/1928), 442 (5/1913-7/1927), 444 (5/1913-5/1929), 451 (10/1909-8/1927), 452 (11/1909-withdrawn 4/1927), 453 (11/1909-4/1929), 454 (12/1909-10/1927), 455 (12/1909-7/1929).

Gresley 17-element twin-tube superheaters were carried by Nos. 450 (12/1915-4/1930), 408 (8/1916-withdrawn 9/1927) and 447 (2/1917-4/1925).  (Two other sets were used in Classes C1 No. 950 and L1 No. 131.)  No. 450 (superheated) received new piston valve cylinders, 20¼in diameter.

All other superheaters were the Robinson type.  These were subsequently fitted as replacements to all engines that previously carried either Schmidt or Twin-Tube types at the removal dates shown in brackets, except for the two noted as withdrawn at these dates (Nos. 408/52).  All engines not listed were fitted with Robinson superheaters before Grouping, with the exception of Nos. 3413/19/28/31/33/34/3/39 which were never superheated.  Full dates of fitting superheating are given by Groves.


Boiler dwg N385 (issued 4/1914 and again 11/1920) was the arrangement for oil burning in 8-wheel coupled engines and 4-4-2s.

No. 412 was fitted for oil burning (3/1912-3/1913).


No. 439 (saturated boiler) was fitted with a Weir feed water heater (8/1912); No 440 (superheated boiler) was fitted with a Weir pump (7/1913-1920);  No. 404 (superheated boiler) was fitted with a Worthington pump and Willans feed water heater (6/1917).

No. 420 CLASS

4ft-8in wheels, cyls 21in x 26in, Gresley Dgm 8 boiler, LNER Dgm 3 boiler

Boiler dwg N264 (-) for 0-8-0 No. 420, and Class H3 Nos. 1640-49
Firebox dwg N265 (-) for N265,
Engine Repair Order (dated 13/10/1913) for the rebuilding of No. 420.

10 sets Doncaster 24-element superheaters ordered (12/8/1913),
Amended to 10 sets Robinson 24-element superheaters (12/11/1913).

The steam chests had 8¾in piston valves.

The replacement boiler (February 1914) was the type fitted to the Class H3 2-6-0s with a 24-element Robinson superheater.

Boiler Order 620 (8/10/1913) was for ten H3-type boilers for Engine Repair Order (ERO) 684, ten more conversions from Class K1 to K2.  The ERO was later cancelled and the boilers were used instead for EO 281 (Class H3).  Thus No. 420 remained the sole rebuild. 


LNER Class Q1 : 40 in service, engines gradually withdrawn down to November 1935
LNER Class Q2 : 14 in service, engines gradually withdrawn down to December 1935
LNER Class Q3 was intact at Grouping : 1 in service, withdrawn February 1937

The engines were renumbered 3401-55 (1924-28).  No. 3417 received 21in diameter piston valve cylinders (3/1924).  As noted already, the engines which had either Schmidt or twin-tube superheaters were gradually altered to Robinson.  Those still with saturated boilers, remained saturated to the end.

Preamble,  Plant Works,  A 4-2-2 A 4-6-2B 2-2-2 C 4-4-2, C 4-4-2T D 4-4-0 E 2-4-0 F 0-4-2,
F 0-4-2T G 0-4-4T H 2-6-0 J 0-6-0 J 0-6-0ST J 0-6-0T L 0-8-2T MC Motor coach N 0-6-2T

O 2-8-0