Your first order of business is to have a shop manual, don’t even attempt to do this job without one.
Moss carries manuals for your car, and I highly recommend you purchase one.
Cylinder head, pushrods and tappets Ok, let’s get started with the actual disassembly of the engine.
If your engine doesn’t have a tappet cover then you will remove them by one of several methods depending on the engine.
For example with Triumph you simply reach into the block and remove them.
The next thing to make sure you have is the correct bolts in the proper lengths needed to mount the adapter to the back of the engine block.
If you are new to British engines, you’ll immediately find out they use mostly SAE fine thread bolts and nuts, not always easy to find at your chain home improvement stores, so a well stocked local hardware store, or fastener specialty store will be your best place to find the right bolts.
Start by removing the connecting rod bolts, or nuts, and separating the rod cap from the connecting rod, now you can push the connecting rod and piston out thru the top side of the block (a rubber hammer handle works well for this).
Make sure to keep one hand at the top of the block to catch the piston and connecting rod as it comes out of the cylinder, so they don’t fall to the ground and get damaged. The cylinders need to be checked by a machine shop for wear and roundness to see if the engine block needs boring. Your machine shop will be able to determine if the block needs boring and what oversize pistons you will need.
Now that the rocker arm assembly is off you can remove the push rods.
the cylinder head from the block and start removing the cylinder head studs.
On a 1275 engine, the cam will have to be removed before you can remove the lifters.
The tappets for any pitting on the surface that contacts the camshaft. If you plan on reusing your tappets you must keep them in the exact order they came out.
There’s an old saying, it’s always easier to take something apart than it is to put it back together.