Kobelt KP12 User manual

Kobelt Manufacturing Co. Ltd.
KP12 & KP14 Hydraulic Thrusters
Owner's Manual
December 2021

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 1 of 46
NOTES:
RECORD DATA BEFORE INSTALLATION FOR FUTURE REFERENCE
Model #:
Serial #:
Date of purchase:
Date of installation:
Motor brand and part #:

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 2 of 46
TABLE OF CONTENTS
1Introduction ............................................................................................................3
1.1 Contact..................................................................................................................... 3
1.2 Safety....................................................................................................................... 3
2Product Description .................................................................................................5
2.1 Overview.................................................................................................................. 5
2.2 Model Code Key....................................................................................................... 6
2.3 Technical Data.......................................................................................................... 6
2.4 Parts......................................................................................................................... 7
3Installation and Location Selection...........................................................................8
3.1 Tunnel Thruster Location Selection and Installation................................................ 8
3.2 Transom Mounted Thruster Location and Installation........................................... 15
3.3 Lubricating Oil System............................................................................................ 19
4Maintenance and Service....................................................................................... 20
4.1 Preventative Maintenance..................................................................................... 20
4.2 Recommended Spare Parts.................................................................................... 20
4.3 Propeller Installation and Removal........................................................................ 21
4.4 Transom Mount Thruster Tube Removal and Installation...................................... 22
4.5 Setting Coupling Distance ...................................................................................... 24
4.6 Bearing Cap Removal & Oil Drain........................................................................... 24
4.7 Oil Changes ............................................................................................................ 25
4.8 Shaft Seal Replacement ......................................................................................... 26
5Hydraulics.............................................................................................................. 27
5.1 System Requirements ............................................................................................ 27
5.2 Installation ............................................................................................................. 27
6Parts Lists .............................................................................................................. 29
6.1 KP12 Tunnel Thrusters ........................................................................................... 29
6.2 KP14 Tunnel Thrusters ........................................................................................... 31
6.3 KP12 Bolt-On Thrusters.......................................................................................... 33
6.4 Leg Subassembly.................................................................................................... 35
6.5 Shaft Subassembly................................................................................................. 37
6.6 Accessories............................................................................................................. 38
6.7 Parts Lists Notes..................................................................................................... 39
7Technical Drawings................................................................................................ 41
7.1 Tunnel Thrusters.................................................................................................... 41
7.2 Transom-Mounted Hydraulic Thrusters................................................................. 43
8Warranty............................................................................................................... 44

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 3 of 46
1INTRODUCTION
1.1 CONTACT
Kobelt Manufacturing Co. Ltd.
8238 129th Street
Surrey, British Columbia
Canada, V3W 0A6
Sales Tel:
Fax:
Email:
Website:
[phone]
[phone]
[e-mail]
www.kobelt.com
This document is intended to clearly present comprehensive product data and provide
technical information to assist the end user in design applications. Kobelt reserves the right,
without notice, to change the design, or construction, of any products and to discontinue or
limit distribution of any products. Kobelt also reserves the right to change, or update, without
notice, any technical information contained within this document.
Kobelt recommends that customers visit our website to check for updates to this Manual.
Once a product has been selected for use, it should be tested by the user to ensure proper
function in all possible applications. For further instructions, please contact our distributors or
visit our website.
1.2 SAFETY
1.2.1 Safety Alerts
Throughout this manual, the following symbols, and their accompanying explanation, are
used to alert the user to special instructions concerning a service or operation that may be
hazardous if performed incorrectly or carelessly. The associated risk levels are stated below.
This symbol indicates an imminently hazardous situation which, if
not avoided, will result in death or serious injury.
This symbol indicates a potentially hazardous situation which, if not
avoided, could result in death or serious injury.
This symbol indicates a hazardous situation, which if not avoided,
could result in minor or moderate injury.
This symbol informs the reader of events not related to personal
injury but which there is a risk of damage to property or equipment.
This symbol informs the reader of safety-related instructions or
procedures.

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 4 of 46
1.2.2 Notice to Installer
Disregarding the following safety measures can result in an accident causing severe injury to
personnel and damage to material assets.
•Only use the product as directed in this manual.
•Never put the product into service if there is evidence of visible damage.
•Never put the product into service before fully completing installation and
commissioning.
•Do not carry out any modifications to the product.
•Only use authentic Kobelt spare parts.
•Observe all local regulations, directives and laws during the installation of this product.
•All installation, commissioning, and maintenance work must only be conducted by
qualified personnel. (For the purpose of this manual, qualified personnel are persons
who are familiar with the assembly, installation, commissioning, and operation of the
product and who have the qualifications necessary for their occupation.)
•Observe all specifications in this manual. If these guidelines are not followed and
damage occurs, the warranty will be voided.
1.2.3 Product Hazards
The rotating components of the thruster can generate forces that
can cause pinch or crush injuries. Keep body parts clear of the
thruster when it is operating. Lock out any power sources before
working on the thruster.
Exercise safety precautions pertaining to hydraulics including:
•Wearing safety glasses.
•Exhausting pressure and locking out the pressure source.
•Being qualified to work on hydraulics.
On standard thruster installations, the mounting saddle installation
to the tube should be considered permanent once installed and
should not be removed. The leg and propeller assemblies can simply
be detached from the saddle when service is required. This ensures
the saddle stays sealed and correctly aligned eliminating the need
for propeller realignment or saddle resealing.
On transom mounted thruster installations, the mounting plate and
saddle installation should be considered permanent once installed
and should not be removed. The thruster leg assembly and tube can
simply be detached from the rest of the installation when service is
needed allowing the mounting plate installation to remain sealed.
To help prevent corrosion, it is strongly recommended to connect
the thruster to the vessel’s existing bonding system. Consult a
marine electrical specialist for advice regarding modifying your
vessel’s bonding system.

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 5 of 46
2PRODUCT DESCRIPTION
2.1 OVERVIEW
The figure below shows a typical tunnel thruster with all of its major components identified.
Thrusters are meant to assist in docking, station keeping and maneuvering in tight spaces and
are usually installed to an athwartships tunnel that goes through the vessel’s hull (tunnel
thrusters). Some thruster models are also offered in bolt-on versions which do not attach to a
tunnel but instead mount externally to the transom of a vessel. Thrusters are powered by a
hydraulic motor which is mounted to the thruster saddle. The direction of thrust can be
changed by reversing the direction of oil flow to the hydraulic motor. All thrusters are
available in aluminum or bronze versions.
Figure 1 –Names of thruster components

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 6 of 46
2.2 MODEL CODE KEY
2.3 TECHNICAL DATA
Your authorized Kobelt distributor typically will also sell you a hydraulic motor that is most
compatible with your vessel’s existing hydraulic system. Given that there is no “standard”
motor, pressure and flow requirements do not depend solely on the thruster model used and
will vary from installation to installation. Table 1 below provides examples of possible
operating parameters for typical installations. Note that operating parameters are also
affected by the vessel’s hull and tunnel geometry.
Table 1 - Hydraulic motor operating specifications
Model
Flow
Pressure
Power
KP 12
18 gpm
68 lpm
2,300 psi
172 bar
25 hp
18 kW
KP 12 HD
20 gpm
76 lpm
2,600 psi
179 bar
31 hp
23 kW
KP 14
24.5 gpm
93 lpm
2,600 psi
179 bar
38 hp
28 kW

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 7 of 46
2.4 PARTS
Detailed parts lists can be found in section 6 of this manual. You should find the following
items when you receive your Keypower thruster:
•A completely assembled thruster which consists of
oHydraulic motor (sold separately)
1
oSaddle
oLeg subassembly
oPropeller
oProp nut
oMounting plate (bolt-on transom thrusters only)
oFibreglass tube (bolt-on transom thrusters only)
•Prop puller tool
•Header tank and its mounting hardware
•Installation bolt kit (tunnel thrusters only)
•Template for thruster tube cut (tunnel thrusters only)
•Backing plate (bolt-on transom thrusters only)
•This manual
Kobelt can supply fibreglass, steel and aluminum tubes for your thruster if needed. If
supplying your own tube, be aware that the wall thickness must be correct for proper
alignment of the thruster; you may be required to build up to the thruster saddle for thinner
tubes. Refer to the table below for the required tube dimensions of each thruster size.
Table 2 –Thruster tube dimensions
Model
Tube ID
[inches]
Wall Thickness
[inches]
KP12 & KP12 HD
12
3/8
KP14
14
3/8
1
Prior to commencing thruster installation, you should note down the make and model of
the motor that has been supplied with your thruster on the space provided on page 1.

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 8 of 46
3INSTALLATION AND LOCATION SELECTION
This section has been prepared to assist the owner and the installer in understanding the
installation of the thruster to the vessel. All work should be performed by a professional who
is competent in marine mechanical installations.
Installation of the thruster involves cutting into the hull of the vessel
and improper material use or workmanship can result in property
damage, and/or a loss of performance.
Care should be taken when selecting a location for the thruster installation as it can greatly
affect the performance of the thruster. A thruster is a low-pressure axial pump whose
performance is sensitive to the interference of the influx of water to the propeller and the
pressure distribution outside of the vessel’s hull. Additionally, the thruster installation can
increase the drag of the vessel if due care is not taken in selecting its location. For the reasons
mentioned, special consideration must be given so that a hydrodynamically favourable and
economically sensible installation is achieved. If the guidelines in this manual are not taken
into consideration, then a loss of thrust should be expected. Best results can be achieved by
consulting with a naval architect familiar with the vessel.
3.1 TUNNEL THRUSTER LOCATION SELECTION AND INSTALLATION
This section describes the installation of the tunnel and thruster to your vessel. You can
either:
•Install the tube to the hull first, and then install the thruster to the tube.
•Make the leg cut out and mounting holes first (steps 1 to 6 in section 3.1.4 on page
13), install the tube to the vessel, then complete the installation by sealing the
thruster to the tube (remaining steps in section 3.1.4).
Note that the following instructions are for tunnel installations only (installing to an
athwartships tunnel through the vessel’s hull), see section 3.2 on page 15 for bolt-on
transom-mounted thruster installation instructions.
3.1.1 Locating the Thruster on Your Vessel
Consider the following when selecting a location to install the thruster:
•Locating the thruster as far forward in the vessel will maximize its effectiveness.
•The propeller’s midline should be located as close to the centreline of the vessel as
possible. The provided cutting template has the propeller midline location marked
on it which will allow you to accurately locate the propeller midline.
•Account for the space the saddle, motor, and any hydraulic fittings and hoses will
take up within the vessel. See section 7.1 on page 41 for the thruster’s dimensions.
•The thruster can be installed so that the drive components are above the tube,
horizontal to the tube or at any angle in between.
•No parts of the thruster are to extend outside of the hull.
•The tunnel’s length, vertical positioning, and opening shape all greatly affect
thruster performance. Refer to Figure 2 on page 9 and accompanying Table 3 for
definitions of these parameters and their recommended values.

KP12 & KP14 Hydraulic Thrusters Kobelt Manufacturing Co. Ltd
Rev A MNL-KP12X-H-TH 9 of 46
Figure 2 –Thruster tunnel location parameters that affect performance
Table 3 –Recommendations for thruster tunnel location.
Dimension
Recommendation
Consequence if recommendation not met
T
•T ≥D*
•T = 1.5D is best
•Insufficient depth can cause air suction
which reduces thrust, increases noise and
vibration, and can damage the thruster.
•Note that excessive depth can be
inefficient and cause excessive roll of the
vessel during thruster operation.
L
•L ≥ 2D
•L ≤ 6D
•Insufficient length does not allow the flow
to stabilize thus decreasing thrust.
•Excessive length increases flow resistance
thus decreasing thrust.
K
•If L < 3D, then
K ≥D/2
•If L ≥ 3D, then
K ≥ D/4
•Circular currents can develop below the
hull of the ship which decrease thrust.
a
•Close to 90°as
possible
•Greater hull inclination results in decreased
thrust (for this reason a bulbous bow
makes an excellent location for a thruster).
S
•S ≥ 0.10D
•S ≤ 0.15D
•Cone (good) or
radius (better)
•Insufficient tunnel fairing causes incoming
water to be excessively turbulent
decreasing thrust.
•Excessive fairing will increase the hull drag
during normal ahead travel.
*Note this dimension applies to the lightest waterline. Vessels used in open seas must also
consider the effects of pitch, roll and wave action on the submersion of the thruster.