If a new diesel owner never learns ANYTHING else from visiting forums
like this, hopefully they will at LEAST learn the value of a few
aftermarket gauges the original manufacturer SHOULD have included in
our trucks as standard equipment!
WHY added gauges? Because the diesel truck manufacturers have a gas
engine mentality where OEM supplied gauges are concerned, and the
engine monitoring that might be adequate for a gasser, is WELL below
the basic needs for a diesel engine!
Personally, *I* consider the absolute need for at least *3* additional gauges:
As a minimum, in addition to oil pressure, alternator and coolant
temperature gauges, turbo diesel engines also need to have exhaust gas
temps, turbo boost and fuel pressure monitored. This is because those
elements go a long way in revealing overall safe and efficient engine
performance as do oil pressure and coolant temps!
Boost pressure readings tell how far up the performance and power scale
the engine is being pushed - the higher the PSI, the greater the load
on the engine. Exhaust gas temps are also an indication to stress and
load on an engine, as well as how efficiently the turbo is supplying
air to fully burn the available fuel.
High exhaust temps combined with low boost PSI CAN be a sign of a
clogged air filter or air leakage in the intake tract, too small a
turbo, or excessively large injectors for the rest of the engine and
it's load. Generally speaking, exhaust temps above a peak of 1300
degrees for short duration, or 1200 degrees for longer periods of load
should be avoided to prevent meltdown of pistons and valve damage - and
damage to the turbo as well.
Fuel pressure is of special importance on 98-2002 24 valve engines to
monitor proper fuel flow to the somewhat sensitive VP-44 fuel injection
pump - altho' ALL injection pump types used in our Dodges will benefit
from monitoring fuel pressures to avoid loss of the cooling and
lubricating effects provided to the pumps by proper fuel flow and
pressure.
Probably the largest percentage of common engine related problems with
our trucks are related to fuel delivery, and will be revealed by fuel
PSI readings under varying operational conditions.
And as a group, the 3 gauges covered here, will provide indicators of
the VAST MAJORITY of commonly encountered engine problems and
performance issues - THAT'S why they are considered to be so basically
important, and why the more experienced diesel operators FIRST question
when discussing a newbies engine problems will likely be
"Do you have gauges?"
Above are seen the pillar mount 2-gauge setup I have installed on my truck - they are Westach brand, and were bought thru
www.genosgarage.com
, and include the top dual gauge Exhaust Gas Temperature (EGT) combined
in the same housing with Turbo boost, which has a top PSI scale of 35
PSI. There are many other vendors of similar gauges in a wide variety
of styles, mounts and pricing.
Below that, is a fuel pressure gauge to monitor fuel PSI right at the
inlet to my truck's VP-44 injection pump thru this connection point:
The tubing seen goes up to where my electric gauge sensor is located, as seen here in the foreground:
And the gauge wires travel on thru a large black rubber grommet/plug seen in the firewall and on to the fuel PSI gauge.
The EGT sensor is attached to the exhaust manifold at a specified location for most accurate temp readings:
The sensor tubing for the boost gauge is just that, a small diameter
tube that connects at the engine intake manifold at a normally plugged
opening to the rear driver side of the Cummins. It's not in a spot
easily photographed, so you'll have to use your imagination.
This thread is intended as a relatively simple overview of added gauges
and their importance to the proper monitoring of our expensive Cummins
engines and related systems. And while the specific truck and engine
bay seen in these pics is my own ‘02, the basic principles will fully
apply to ALL year models of the Cummins equipped Dodges.