If CNG is to be used in Diesel engine, what changes to be required?

Answer 1

What he said is right, if you want to run it off of CNG, now if you want to use it to add performance, kinda like NOS on a gas vehicle you can purchase a kit. But no major changes are required.

Answer 2

There are a lot of Changes to be made if CNG is to used in Diesel engine.
1. The Cylinder head need to be changed as we need to install the Spark plugs instead of the Fuel Injectors( Diesel) .
We need to reduce the compression Ration from 21:1 (approx) to 9: 1( for CNG).

2. We need to install a firing / Ignition device to send spark to the spark plug.

We need to change the Manifold or modify the existing manifold to plumb the gas ( CNG ) into the inlet manifold

3. We need to install the Venturi to control the gas / air mixture

Then of course we need to change the piston / cylinder head etc and all these changes will involve a complete engine change.
Hence to convert a Gasoline ( Petrol) engine to CNG is much easier. You will also need a tming device for the ignition system and many other changes as well which I can discuss in detail if needed,

Answer 3

CNG can not be used in diesel engines, it can be onley used in petrol and gas engines.