Upon receipt of any cylinder heads they are generally checked for straightness, the overall condition of the head is assessed and if required general recommendations of work needed are made.

This may range from a simple re machining of the gasket face to replacing all valve guides, valves and seats.

Cylinder heads can be pressure tested on our 'Delta Custom' pressure testing machine, this is to find any cracks or leaks that may be within the head, this test is highly recommended before any further work is carried out.

Here you can see what happens in one of the instances of a crack being found; Once the head has been sealed and pressurised, water has been added, instantly the problem area can be seen a crack has been found.

You can see here, the valves have been cleaned dimensionally checked and the mating face re machined for a perfect seal.

Here is our valve grinding A.Z machine in action.

It is essential that the valve seat angle be perfectly correct, and concentric with the valve guide to give a gas tight seal. After the seat angle has been re machined the corresponding valve is inserted and a vacuum test undertaken to ensure a good seal.

No lapping in is necessary.

Here is our V.V 80 valve seat cutting machine, this machine's cutting head floats on air to allow perfect alignment between the cutter and the valve guide. When this is correct the cutter head is locked hydraulically in position prior to any cutting operation.

If distortion has taken place, within an acceptable limit the gasket face can be re machined; For aluminum heads we use a polycrystalline diamond tool bit, and for cast iron a cubit boron nitrite bit is used to ensure the correct surface finish, as stipulated by gasket manufacturers.