Engineering Recommendation For Using OCV Kits For School Busses

Installation Instructions
Engineering Recommendation For Using
OCV Kits For School Busses
The recommendations will be made for two types of Cummins engines:
1. Busses fitted with Cummins ISB 5.9L engine (engines manufactured from
1998-2002)
2. Busses fitted with Cummins B series and/or mechanical engines
Busses fitted with Cummins ISB 5.9L engine
(engines manufactured from 1998-2002)
Figure 1: As seen in the above picture the newer ISB engines have a factory breather
assembly located on the left side of the front wall of the engine, just behind the fan
Use the new Dodge Ram Kit, CV 50115. This kit along with the installation
instructions should have all the components and hoses that will be required to
change the factory fitted breather with the Fleetguard Enviroguard OCV breather.

Busses fitted with Cummins B series and/or mechanical engines
Use the Crankcase Ventilation Kit, CV 50106 and the mounting bracket
#393814000S. The recommended modifications are:
Figure 2: This mechanical Cummins engine breathes from a location that is on the rear left
side wall of the engine under the rockerbox, as approximately shown by the yellow oval
It is recommended that the OCV breather should be installed on the front right
side of the engine compartment as shown in the figure below:
Figure 3: The physical location of the Fleetguard Enviroguard OCV breather in the engine
compartment

The mounting bracket #393814000S (optional with the Kit CV50106) should be
used for installing the OCV breather to the wall of the engine compartment as
shown in Figure 3 above. This bracket is supplied as a flat component and it
should be bent approximately 1.5” from the top two OCV breather mounting hole
locations as shown in the Figure 4.
Figure 4: The estimated 1.5" from the top two OCV breather mounting hole locations to
where the flat bracket should be bent at 90°
The vent line on the left rear corner of the engine should be attached to the new
¾” vent line (a 5/8” to ¾” adapter is included in the kit if needed). This hose
should be routed along the wall of the engine compartment to the OCV breather.
It is highly recommended that the hose be shielded from the hot areas around
the exhaust manifold on the right side of the engine. A metal tube could be an
alternative to using rubber hose along this area.

Figure 5: The route for the vent hose from the engine wall on the left rear of the engine to
the front right engine compartment wall where the OCV breather should be installed
The orange lines on the above figure signify areas where the vent hose/tube
should be shielded from the hot areas of the engine to avoid overheating of the
rubber hose. IF THE VENT HOSE/TUBE IS LESS THAN 4” FROM THE
EXHAUST MAINFOLD, ONLY A METAL TUBE SHOULD BE USED,
OTHERWISE FOR DISTANCES MORE THAN 4” CAREFULLY SHIELD THE
RUBBER HOSE IN THE HEAT INTENSE REGIONS.
Connect the drain line from the OCV breather to the engine oil pan as shown in
the INSTALLATION INSTRUCTION booklet provided with the kit.
Caution: There should at least be a 14” vertical clearance between the breather assembly
and the drain port into the engine oil pan. Do not install the drain line hose to the engine
oil pan so that there is an oil trap along the path (make sure that it does not go up and
down along the way). Make sure that the provided check valve is always in the vertical
position.
LT32528
©2004 Fleetguard Inc.
Printed in the U.S.A.
For more information, contact Customer Assistance at
1-800-22-FILTER (1-800-223-4583), fax 1-800-999-8664,
or visit us at www.fleetguard.com.