Followers of this thread may remember that we said that it was our ambition to install the engine and gearbox into the chassis now as soon as possible but that it would be necessary to have the chassis back on all four wheels so that we could manoeuvre it under the chain block, thus being able to lift the engine and gearbox comfortably and under control to drop into the chassis. There was still some work to do to the axle and brakes before the wheels could go on but this has all now been done with the exception of making the two Dust Shields for the Brake Drums. Steve has this in hand but has been rather diverted this summer with other things that he wished to do – and these included the construction of a Lorry Shed adjoining his home which could comfortably take the Dennis – with its canvas erected and which would be its permanent home. The shed has been completed apart from the Doors and wiring it and these final things are under way. The shed or “Motor House” is a magnificent structure and we will leave Steve to post a picture of it if he so wishes!
So then thinking about the engine mountings, this is what we were faced with. The engine is designed to sit on two pieces of 3” x 3/8” angle attached to the inner sub-chassis. The angle on the off-side – or right hand side is firmly bolted to the chassis with two clusters of five, 1/2” bolts whilst the angle on the other side is attached to the sub-chassis by one large “Pin” on which the steel angle can rotate slightly, fore and aft, to compensate for any twisting in the chassis in service. The engine is bolted to these two steel angles with two 3/4” diameter bolts in each angle.
So this arrangement is designed to eliminate any stress on the feet of the engine through its four bolting points – if it was all totally solid, then there would be a possibility of damage to the engine with any twisting of the vehicle in service with the worst scenario actually being a break in the engine casing and its bolting feet.
The only part of the original engine mounts remaining under the Shepherds Hut chassis was the “pin” mentioned above so we were faced with making new parts.
Turning first of all to the “off side” angle, then this was quite straight forward to make. The Bolting holes were picked up from the original holes in the sub chassis and caused no difficulty. Many years ago, Steve was working in Portsmouth and was living in a Flat there– this was during his student and post-student days and at that time, the Thornycroft J Bus now with the Hampshire County Museum Service in Basingstoke was stabled in the commercial bus depot nearby. With the blessing of a very helpful and co-operative garage foreman, Steve spent many evening crawling all over the bus, sketching and measuring everything in sight and it is those sketches and measurements from all those years ago that now prove to be invaluable. From this information, we could see exactly what the layout should be of the mounting angles and what the shape of the cut outs are and where they should be in the angles.