Basic system here, why are we messing about with something that a little knowledge can solve, has he answered the question asked by Dave Cheesman (I may have missed it). At the moment I see no need then more than basic diesel knowledge and basic tools, forget gauges and meters etc.
How did we manage with basic system before (I thought I read that old diesel system were very easy to work on).
Basic system details would have been a start, engine coded, diesel pump type and number, egr system (they vary, from none to two solenoid to three solenoid).
Back to the same problem here, lack of system training.
Dave
I wasn't giving Smart arse comments but see people always looking at the none important problems first (why make it complicated). In this case why worry about vacuum build up, the use of one of our senses would do.
Dave
"Hi Peter
It is one thing to be able to measure the degree of pressure, on both sides of atmospheric (vacuum & positive pressures), but what I am hinting at is, how can we verify that a pump is capable of moving the specified volume of air, in a given period?
In a similar way that we discuss not just fuel pressure, but flow also, the same rules apply to vacuum pump functionality.
I have seen many pumps that will achieve the magic 20 inches, but the fact that they take 45 seconds to do so, gives rise for a harder look."
Pressure drops across sysems on fluids of all types has been around and checked for longer than I can remember and has always been checked and monitored, supply and demand, if the demand is greater than the supply then the supply has a problem (monitor the last item in the system).