Air ride

[Dave Atherton]

Ed, the intake is in pipe coming from air filter for engine this correct location. Question number two,
information is stright off Cat SIS about air pressures and Spec's with air compressor. this information
is used for on-road trucks and that standard is D.O.T. ,standards that truck repairs have to comply
with.  Does the Motorhome have there own standards ? starting to wonder because Buses use the same
air ssystems as trucks. let touch again about the Bendix Duraflo 596 it has one D-2 air governor that
can be adjusted. Than the Bendix Duraflo 596 with a synchronization valve that is preset at 110 psi and
130 psi and cannot be adjusted. Point I made very clear, Keith made call and found air governor had
to be replaced because it could not be adjusted. this tells me if Keith has the synchronization valve of
which party Keith called assume that than air pressures on his motorhome have to fall with in the higher
air pressures. This Question can only be answered when Keith finds what air compressor he has on his
Cat C-12. Some thing else they do sell new sychronization valves ( why is this because possible problem
having to do with air pressure with this valve.
I have presented Fact from Bendix Air System Troubleshooting and Cat SIS information that
pertains everything with the C-12 engine. And again Ed may be the motorhome people are
exempt from standards same as not having a CDL license to drive a motorhome.That is about
all I can do to help you guys out. Dave Atherton Retired Cat Mechanic

[Dave Atherton]

Gentleman, I just made a reply about location of intake for the air compressor. but somehow it got
lost. it is in tube from air filter. At this point I do not have anymore current resource to get information
from. What I have used is the Bendix Air Systems Troubleshooting, and Cat SIS information that is
also current. D.O.T. has set a standard that all repairs have fo fall within there rules for on-road trucks.
Maybe motorhomes are exempt from D.O.T. standards because I'm begining to think so. we seem
to question the information on the synchronization valve pressure that is preset and cannot be adjusted
if your C-12 has that valve than that is where pressure will be, but we do not even know if Keith has this
new style valve. The party Keith called seem to think he does because of statement have to replace
air governor because cannot be adjusted. You guys have better infomation on the subject than I do
so I'm going to back out of this.  Dave Atherton Retired Cat Mechanic

[Edward Buker]

Dave,

There is no piping from the air filter chamber to the compressor. There is a pipe from the intake manifold on the other side of the block, as I mentioned, so that seems like the source for the compressor air inlet.

Later Ed

[Dave Atherton]

Ed, there are 3 ways the Air compressor will gets sourse of air from. Number 1 from a air filter on
air compressor housing itself. Number 2 from pipe connected into air filter and engine turbo charger.
Number 3 air compressor gets air supply from intake manifold on engine via of 1 inch hose. while
on subject I have seen all three systems on motorhomes, There seems to be no standard when builder
puts house over the motor. Again answer to your question, It may not be the same for others as yours.
The engine S/N number plays a big part in where you going with this. Different S/N will change how
add-ons location will be different from engine to engine. Mounting of the fuel filter is a good example
to play with. Cat C-9 engine the air governor is remote from air compressor to upright support on
right side of engine in back . Engine Data Connector another good example, some models along inside
of right frame rail to above rear back of engine. last the big air filter it self, different locations mean
different mounting of add-ons. I answered your three fold as way Cat SIS lays out info for many different
locations of add-on . again there is not one standard set in stone. Dave Atherton Retired Cat Mechanic