We are looking at the WPS transducer connected to diesel injector back leakage

By no means does this replace the bottle test but is in addition to

The beauty of this is we can actually go on a road test

Assuming we have got the drain and the spill set up correctly and securely

So we will no switch on the WPS

It is important to have the pressure sensing tap open to atmosphere

Because at this point we are running through a calibration

So we are setting the zero to atmospheric pressure in every scale

Now because we are measuring spill

We are going to measuring spill or back leakage through the measurement port

Through the measurement chamber

And it is important we don't offer a restriction here

So we must have a flow through and straight back out

So how we do this

Is by using a cable tie

That way we can keep the bleed or drain tap open

To demonstrate

Tap is closed

Tap is now open

So any pressure we apply to here

Back leakage will drain straight through into our spill bottle

Connection wise we are connected to number 4 injector

So it is at the end of the injector rail

Connected into our pressure port

We have the pressure bleed tap open

So diesel back leakage can pass through the WPS

Through the measuring chamber

And straight out through the spill into the collection bottle

We have a breakout lead connected to injector 1 measuring current

So now we can monitor the spill from each injector

The pressure in the spill in the back leakage from each injector

Whilst monitoring the signal from number 1 injector

It is important to note that when we start the vehicle

If we can hold the WPS pressure transducer upside down momentarily

We can bleed any air that is trapped within the pressure port

Through the measurement chamber and out through the drain port

Now start the engine

Engine revs

Engine stops