What is this?

[rustyp]

Sorry no pics so will have to describe.....

Under the diesel pump there is the power steering pump. In front of the engine at the same level as the steering pump is another "thing" this thing has a pipe leading off it that goes up in front of the engine with a branch off to the cold weather exhaust valve control (iirc).

Is this "thing" a vacuum pump? Where does the pipe go? Brake servo? Cheers - Russ

[sparkymik]

Sorry no pics so will have to describe.....

Under the diesel pump there is the power steering pump. In front of the engine at the same level as the steering pump is another "thing" this thing has a pipe leading off it that goes up in front of the engine with a branch off to the cold weather exhaust valve control (iirc).

Is this "thing" a vacuum pump? Where does the pipe go? Brake servo? Cheers - Russ

Have a look in here...http://www.lushprojects.com/bongoparts/pages/

Sparky

[rustyp]

I was right - it's a vacuum pump but what does it do/run - I know there is a feed off to the cold weather starting exhaust valve, there is I imagine a feed to the brake servo? (Why doesn't it take vacuum upstream of the turbo on the inlet side?) there is one more feed off at the top where does this go - my quest continues...

Thanks Sparky

[Simon Jones]

The vacuum pump feeds the brake servo, exhaust valve (where fitted) as well as a few actuators for the EGR valve & throttle actuator to increase the revs when switching the aircon on. You can also tap into the pipe to fit a Waeco MS50 cruise control.

With regard to the other question, as I undertstand it: diesel engines don't produce a vacuum in the inlet manifold in the same way as a petrol engine. This is because it is open to atmospheric pressure all the time as there is no butterfly valve / venturi to suck against as you have on a traditional carburettor. On a diesel, the amount of air entering the engine is pretty constant & its just the amount of fuel that is varied, whereas a petrol engine varies the fuel & air mixture.