Onan MDJF Series Operator's Manual And Parts Catalog page 12

IMPORTANT: DO HOT USE SCOOP TYPE WATER INLET
FITTINGS when installing an Aqualilt mulller. Forward lacing
scoops develop sullicient ram pressure to lorce water past
the set's water pump, Hooding the exhaust system where it
may (low back, Hooding the engine cylinders. This can
happen only il the electric set is not running and boat is
underway.
1. Secure the muffler to the predetermined location (within
ten-feet of the engine exhaust outlet) using " L "
brackets (Figure 6) or other suitable mounting devices
such as wood blocks or metal straps. Flexible mounts
may be used if so desired. Allow for air passage under
muffler to prevent condensation.
O U T L E T
N O T T O
E X C E E D
1 I N C H •
• L " B R A C K E T
( M I N I M U M
O F 3 )
< j £ i L O C K W A S H E R
j g * - N U T B A S E
S H O R T N I P P L E
D O U B L E T A P P E D
T A N K B U S H I N G
LONG NIPPLE -p
, ( I N S I D E V .
M U F F L E R )
r
S H O R T
N I P P L E
R E D U C E R P I P E
B U S H I N G
N O T E : L O N G N I P P L E G O E S I N S I D E T A N K
FIGURE 6. SECURING THE MUFFLER
FIGURE 7. A Q U A L I F T MUFFLER
3.. Connect the exhaust line to the muffler outlet and to the
upper elbow. A conventional automobile tail-pipe hanger
bracket may be used to hang the upper elbow. Rigid pipe
may be used in place of flexible hose for certain applica-
tions. There must be a pitch of one-half inch per foot
(i.e., a 2 - 1 / 2 " drop for a 5' run) in the exhaust tubing
between the engine exhaust elbow and the muffler inlet.
Muffler may be mounted below the level of the engine i f
necessary. A minimum drop of one-foot is necessary be-
tween the engine exhaust outlet on the hull to prevent
water from washing into the system (see Fig. 3). An in-
crease of one standard pipe size for every ten running
feet of exhaust from the muffler to the exhaust outlet is
necessary to prevent excessive backpressure.
p T ^ C j r r ^ Do not drill holes higher than one inch
L A 5 5 - A - P A A ^ X above the extreme lower edge of the
muffler when installing mounts.
4. Connect the exhaust line from the upper elbow to the ex-
haust outlet on the hull. The exhaust outlet on the hull
must be positioned so that a minimum ot water will enter-
while at anchor or under way.
Important: Be sure all liftings are tight.
2. Connect the exhaust l i n e ( l 1/2" )to the marine elbow on
the engine and to the exhaust inlet on the muffler. The dis-
tance from the base of tHe muffler to the upper elbow on
the exhaust tubing from the muffler outlet must not exceed
four-feet (see Figure 3).
L^j^^^x^^^i interior
the lile expectancy;
on the mulller will damage the
protective coating decreasing
11