INSTALLATION
Use this procedure to determine whether or not the
boat’s transom height is correct for the engine’s
shaft length:
WARNING
Set the motor on the boat’s transom and adjust the
angle so the anti-ventilation plate is parallel with the
boat bottom. Refer to Power Trim and Tilt.
Your engine must not exceed the maximum
horsepower indicated on the boat’s capacity
plate. Such overpowering can cause loss of
control. Contact your DEALER or the boat’s
manufacturer if your boat lacks a capacity
plate.
Boats designed for remote-steered engines
might be overpowered by a tiller-steered
engine of the maximum rated horsepower.
Ask your DEALER or boat manufacturer if
you are unsure about your boat’s suitability.
Incorrectly matched boat and engine tran-
som heights can cause boat instability and
loss of control. Refer to Transom Height and
Shaft Length.
Prevent lateral movement and possible
engine loss by using the mounting hard-
ware supplied or hardware of sufficient size,
strength, and quality. Refer to Installing the
Engine.
The resulting position of the anti-ventilation plate
must be 0 to 1 in. (0 to 25 mm) below the boat’s bot-
tom.
IMPORTANT: If the anti-ventilation plate falls out-
side the 0 to 1 in. (0 to 25 mm) range, the installa-
tion is not considered normal. The motor shaft
length must be changed or the boat’s transom must
be modified.
Lower than recommended – serious powerhead
damage could result from water entry into the lower
engine cover or overloading from an under-revving
propeller at wide open throttle.
A mounting surface that is damaged or too
thin to support your engine while underway
might fail during operation, causing you to
lose control. Be sure the boat’s transom or
mounting bracket is structurally sound and
between 1 5/8 in. (41 mm) and 2 3/4 in. (70
mm) in thickness.
Higher than recommended – serious powerhead
damage could result from inadequate cooling or an
over-revving propeller. Propeller ventilation (slip-
page) often occurs, resulting in poor boat perfor-
mance.
On a specialty hull, non-planing hull, or on a boat
with a curved transom, these guidelines might not
apply. See your DEALER for special installation in-
formation.
TRANSOM HEIGHT AND SHAFT
LENGTH
The transom height dimension listed in Engine
Specifications, is the height of the boat transom
your engine needs. This dimension is measured at
the transom centerline, perpendicular to the bottom
of the boat.
1.
2.
3.
Transom Height
Anti-ventilation Plate
Final position - 0 to 1 in. (0 to 25 mm)
Installation - 47
| Categories | BRP Brand Manuals, Johnson 4-Stroke Manuals, Johnson Brand Manuals, Johnson Outboard Manuals |
|---|---|
| Document Type | Boat Motor Manual. Marine Operator's Engine Guide. |
| Tags | Johnson 25 hp, Johnson 30 hp, Johnson PL4 |
| Model Year | 2004 |
| Download File |
|
| Document File Type | |
| Publisher | johnson.com |
| Wikipedia's Page | Johnson Outboards |
| Copyright | Attribution Non-commercial |
(1 votes, average: 4 out of 4)
Marine readers have rated 2004 Johnson 25 30 hp PL4 4-Stroke Outboard Owners Manual 4.0 out of 4.0 based on 1 product reviews. Handy as a manual didn't come with my boat