6th August 2012

This is the first of an occasional series of blogs about the restoration of my Ruston-Hornsby 4AP. I will provide more background later but the engine was bought as a collection of bits. Today I had a go at removing the 3 gib keys on the crankshaft. Since I bought the engine 20 years ago I have been occasionally spraying the gib keys with WD40 ready for this event. I recently bought the Claas 'Curved Key Drawer' - Part No 0001818341 from the local Claas agricultural equipment dealer. The set up was fairly obvious although the key drawer does not have parallel sides and should be placed the right way up. For the first key a packing piece was placed on the hub of the pulley so that the curved drawer could fit properly (without the packer, the point of the drawer would foul with the pulley rim). The G clamp held the packer and prevented the drawer from lifting out. Once the drawer was set up, the pulley was placed against a wall to provide support and the drawer hit with a 3lb lump hammer. A couple of good belts and it moved. With a bit more tapping it came out. The key has been put in a plastic bag and labelled to avoid muddling them up.

Using a piece of hardwood and the lump hammer, the pulley was knocked until it started to move. Gradually the pulley was worked loose and then slowly worked off the crankshaft.

The set up for the removal of the gib key from the pulley

 Then on to the next two keys and with a similar arrangement (without the packer), the keys were out.

Set up for the removal of the first of the flywheel keys

The flywheels were not at all loose and it was not clear what the next step would be. A look back at Nigel McBurney's series on the restoration of a Ruston-Hornsby IP in back issues of Stationary Magazine and I decided to put the crank and flywheels on the crankcase. This would allow me to work more easily on easing off the flywheels. After a bit of effort the crank was loaded on to the bearings and the weights chocked in the crankcase with a block of wood. I do not have the upper bearing shells so could not fasten the crank down. However with a bit of careful rocking the flywheels were worked loose. The next step is the removal of the flywheels and then the balancing weights and sideshaft gear drive off the crank.

The crankshaft on the crankcase. The crankcase is on a temporary trolley made for the restoration.