The rocker gear was gummed up so was completely stripped down. Wear was noted on the rod, so one was salvaged from another engine. Reassembly was quite tricky and I found it very easy to misalign bits and also get bits in the wrong order. It took a few attempts.
Since the remaining parts had arrived the engine re assembly gathered pace. I sourced some nuts from an MG supplier for the head, although these were later replaced with standard nuts to ensure proper torquing. Owing to damaged valves, a new set were fitted and lapped. This was initially done by hand, but I created a connection to a drill. Great care was needed to ensure the valve stem was lubricated & that drill speed was not excessive. It is vital to keep lifting the valve of the seat to ensure the cutting paste gets spread evenly. This process raised a few eyebrows, but it did work.
With the valve collets and springs fitted the head went on and was given an initial torqueing. The head gasket for the 500cc was different to later ones. However, it is easier to find modern replacements. This does present potential problems however, since the oil and water channels do not always line up properly. Later gaskets are also designed to be applied without any sealants and instead use the heat of a dry engine run to activate adhesive. I did later find a supplier that makes head gaskets very close to the OEM type.
After re torquing, the carefully numbered push rods & the rocker gear were dropped on. Again, there are different versions so care had to be taken that what I had worked with the early type of cylinder head.
Feeling quite pleased with myself it was then pointed out that some of the valve return springs were upside down ! To rectify this problem meant being able to compress the valve springs without taking the head off again. With thanks to Fifers Reliant Hints & Tips, I hit upon a solution. I sent my Brother the dimensions for a tool that can be used to compress the springs in situ.
After a few days the engineered tool arrived. It works by fastening to stud to provide the leverage. The aperture over the valve allows the collets to be exposed. The valve is prevented from being pushed down by inserting some thick mains electricity flex through the spark plug hole.
With the springs now all the right way round, the rocker gear goes back on.
