Not starting

It is unlikely that this engine has an air lock in the fuel system as there is a vent in the filter that will purge air so that the lift pump can push the air out as it pushes fuel through the system.

Basically diesel systems that get air locks are ones that don't have vents in the system to allow the pump to purge the air as they push fuel. So if there is no place for the air to escape then the lift pump cannot overcome this and it does not start.

See the attached below for more detail on this.

One way to confirm a fuel issue on this engine is to use starter fluid that is about 80% ether.

If the engine starts on this then we have a fuel issue that we will need to dig into further.

More than likely this is an issue but we may have a injector issue on this as they can get high return which means they are returning too much fuel to the tank rather then deliver it to the cylinder.

However, if you have not done it, I would change the fuel filter and then prime the system a number of times before trying to start it and see if that gets it started. Also, make sure the vent is clean and able to vent the air. You will see where this is in the diagram below.

please run through all this info and let us know what you find with this. Thanks