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4F 4027


4F 0-6-0 4027

4F 0-6-0 4027

The Railway is currently restoring the National Railway Museum’s Fowler class 4F steam locomotive, number 4027, which was the first steam engine to be built by the newly formed London Midland and Scottish (LMS) Railway in 1924. The 4F was an 0-6-0 freight engine, originally designed by Henry Fowler for the Midland railway in 1911. In total 575 of these locos were produced of which only 3 survive in preservation.

Back in 1980 4027 took part in the 150th anniversary of the Rainhill trails.


Overhaul Progress

The loco is now under going a major overhaul. Most of the bottom end of the engine has been completed with the main work currently focusing on its boiler and cylinder block.


Autumn 2017

New brake hangers and brake blocks have been machined and drill by Tony Goddard. The brake blocks (right picture) hang on the brake hangers (left picture) and rub on the metal tyre surface of the wheel to slow the train down. On a steam loco the brake mechanism is usually driven from a vacuum or steam cylinder.

The brass ‘bonnets’ for the snifter valves have been machined from rough castings and refitted back together. Paul & Dave have done a fantastic job with these, which were very difficult parts to machine and required a special rig to hold them whilst being drilled with all the holes. This job really is a case of measure 3 times & drill once.

One of the snifter valve ‘bonnets’ all drilled and machined, ready for refitting.

Snifter values are used to help prevent a vacuum from being formed in the cylinders when the engine is coasting and the regulator shut. Otherwise there would be a risk that ash and shoot from the smoke box could be pulled into the steam chest causing damage to the linings & ports.


Both snifter vales re-assembled and ready to be fitted to the loco.

Seems a shame they will be hidden out of site underneath the engine given all the hard work.





The reverser mechanism has been refitted to the loco. This device enables the driver to change the duration steam is used to push the pistons. A high cut off such as 75% is used when starting the loco. This means that steam is applied to the piston for 75% of it’s stroke. Once the engine gets up to speed, the cut off is reduced, saving on the amount of steam the engine requires, much to a fireman’s delight.



Summer 2017

The 4F’s brake hangers have been refurbished and all the brake rigging has been repainted.

The cylinder relief valves and drain cocks have been overhauled. These help to keep water from building up inside the cylinder and therefore damaging the motion, since unlike steam, water isn’t compressible.

The snifter valves are being overhauled with new bonnets being machined. Snifter valves help to prevent the actions of the piston creating a vacuum in the cylinder when the loco is coasting with the regulator shut, which risks sucking in ash from the smoke box and may damage the cylinder linings.

The valve spindles for each of the two piston valves were found to be worn, so new ones have been machined.


Worn Valve Spindles


New vale spindles and rebored cylinder covers











Spring 2017

20170617_122902_640x480A big shunt was done, moving the 03 diesel from the erecting shop to the barn, in order to allow the 4F to be moved under cover in the erecting shop.

Work has started on overhauling the brake rigging, cleaning the parts down, re-machining and repainting.





January 2016

The blast pipe is under refurbishment with fresh coats of black heat resistance paint applied. This will sit in the smoke box and directs the exhaust steam up the chimney.

2017-01-21 15.25.01

4F’s Blast Pipe









November 2016

Numerous parts of the 4F loco are currently being painted in preparation for refitting once the boiler is complete. Denzil can be seen painting the front Vacuum Brake Pipe.

4F Denzil Painting Vac Pipe

Denzil Painting the Vac Pipe











August 2016

Shotblasted 4F cylinder block

Shot blasted and polymer coated cylinder block

The 4F’s cylinder block has been shotblasted and then coated with a protective polymer resin coating, in the hope it will help prevent further corrosion of the cylinder block casting, which has occurred over the many years of use.







Paul West feeding the shotblasting unit with angular grit granules. Kev is in the tent blasting away at the rear dragbox


Taking advantage of the shot blasting equipment being setup the drag box and other components were also shot blasted and repainted.