What causes a Kohler Marine Equipment engine to knock?
- WWilliam SmithSep 12, 2025
If your Kohler Marine Equipment engine knocks, use the proper fuel type, consulting the fuel supplier if needed and bleed air from injectors.

What causes a Kohler Marine Equipment engine to knock?
If your Kohler Marine Equipment engine knocks, use the proper fuel type, consulting the fuel supplier if needed and bleed air from injectors.
What to do if Kohler 3.5EFOZ Marine Equipment engine starts but does not continue to run?
If your Kohler Marine Equipment engine starts but doesn't continue to run after releasing the start switch, check the high exhaust temperature (HET), low oil pressure (LOP), and/or high water temperature (HWT) shutdown switches. Also, check the oil pressure and pump, and verify the AC voltage.
Why does my Kohler 3.5EFOZ overheat?
If your Kohler Marine Equipment overheats, start by checking the intake and outlet openings and the raw water strainer to ensure proper cooling. Replace the thermostat if it's inoperative. Service the air intake screen if it's clogged. Reduce the load if the engine is overloaded. Flush the cooling system if it needs cleaning. Replace any inoperative temperature switches. Finally, inspect the water passage for any cooling water leaks.
What to do if Kohler Marine Equipment cranks but will not start?
If your Kohler Marine Equipment cranks but will not start, first check the shutdown switches. Ensure you have enough fuel by replenishing the fuel supply and opening the fuel shut-off valve if it's closed. Replace the fuel feed pump if it's inoperative. Service the fuel filter element if it's clogged, and bleed the air from the fuel system. If there is water or dirt in the fuel system, drain and flush it. Also, check the battery, recharge or replace if weak or dead. Clean and retighten the faulty ground connection. Clean or replace the air intake screen, if clogged.
Why is my Kohler 3.5EFOZ losing power?
If your Kohler Marine Equipment is losing power, service the air intake screen if it's clogged, and replace the fuel if it's bad or stale. Check the governor and adjust it if the engine is not operating at the rated RPM or if the governor adjustments are incorrect. Clean the carbon from the cylinder head if there's a carbon build-up. Inspect the cooling system to ensure proper cooling. Check the fuel lines for any restrictions. Reduce the load if the engine is overloaded. Service the fuel filter if it's dirty, and clean the cap in solvent and blow it dry if the vent in the fuel tank is obstructed.
What causes a Kohler 3.5EFOZ Marine Equipment to stop suddenly?
If your Kohler Marine Equipment stops suddenly, replenish the fuel supply if it's out of fuel and service the air intake screen if it's clogged. Reset the circuit breaker if it has tripped in the controller. Replace the seawater pump impeller if it's inoperative, and clean the seawater strainer if it's clogged. Check the fuel lines and the fuel tank for any restrictions. Clean the fuel filter if it's dirty. Check the oil pressure and pump if there's no or low oil pressure. Check the engine cooling system if there's high temperature. Check the HET, LOP, and HWT shutdown switches if they are inoperative.
What causes abnormal noise in Kohler 3.5EFOZ?
If your Kohler Marine Equipment makes abnormal noise, add lube oil if the lube oil level is low and tighten the hardware if there is a loose bolt or screw.
Why does my Kohler 3.5EFOZ starter crank slowly?
If your Kohler Marine Equipment starter cranks slowly, check the electrolyte level and specific gravity (for batteries with filler caps only) if there's low battery output. Use proper viscosity oil if the lube oil is too heavy. Clean and tighten loose connections if there's loosened or corroded wiring.
What to do if Kohler 3.5EFOZ starter does not work properly?
If your Kohler Marine Equipment starter does not work properly, clean and tighten the loose connections. Check the electrolyte level and specific gravity (batteries with filler caps only) and check battery voltage if there is low battery output power. Replace the starter solenoid if it's inoperative. Replace the switch if the start/stop switch is inoperative. Check the wiring if it's inoperative.
How to reduce noise from a Kohler 3.5EFOZ Marine Equipment unit?
If your Kohler Marine Equipment is noisy, check the exhaust system for leaks and ensure it's securely installed, looking for loose parts. Inspect the vibromounts for any breaks or damage. Check the clearance to ensure the unit isn't hitting the craft structure or compartment. Install approved insulation if there's no compartment sound insulation. Tighten all bolts if there's loose or vibrating sheet metal.
| Brand | Kohler |
|---|---|
| Model | 3.5EFOZ |
| Category | Marine Equipment |
| Language | English |
Record product identification numbers from the generator set nameplate(s).
Record product identification information from the engine nameplate.
Covers operation, maintenance, troubleshooting, and repair of AC marine generator sets.
Details generator models, dimensions, weight, air requirements, fuel consumption, and electrical specs.
Illustrates service-side and engine-end views with component identification.
Lists engine specifications including manufacturer, bore, displacement, horsepower, and oil capacity.
Provides torque values for various engine and generator components in Nm and ft. lbs.
Outlines essential checks before starting the generator set for continued satisfactory operation.
Recommends seasonal inspection by Coast Guard Auxiliary or authorized dealer for safety.
Specifies angular operation limits for units, illustrated with a chart.
Notes specific approval for below-deck operation, complying with EU noise standards.
Advises weekly operation under load for one hour with an operator present.
Details the steps for starting and stopping the generator set, including important notes.
Provides general maintenance guidelines, safety precautions, and service intervals.
Presents a detailed service schedule based on hours or months for various systems.
Covers oil specifications, checking oil levels, and procedures for oil changes.
Discusses battery care, handling sulfuric acid, and precautions against explosion.
Outlines procedures for storing the generator set for three months or longer.
Instructions for cleaning and replacing the air intake screen and silencer assembly.
Details inspection points for the exhaust system, focusing on carbon monoxide hazards.
Describes checking the mixing elbow for carbon buildup and corrosion to prevent exhaust leaks.
Contact Kohler distributors for professional advice and service support.
Covers general fuel system safety, description of operation, and installation notes.
Specifies diesel fuel quality requirements and precautions for storage and handling.
Explains the function of the fuel filter and provides cleaning/replacement procedures.
Details injector cleaning, pressure testing, and adjustment procedures.
Explains the function of the device used to facilitate engine starting.
Describes how to adjust the fuel starting delivery point for proper engine operation.
Details how to obtain correct fuel pump adjustment timing using flywheel and crankcase marks.
Provides instructions for installing fuel pump and gear cover, including distance measurements.
Outlines the procedure to remove air from the fuel system to prevent starting issues.
Explains the governor's function in maintaining engine speed and its construction.
Describes the direct seawater cooling system, impeller pump, and thermostat function.
Details thermostat settings and its role in controlling cooling water circuit temperature.
Provides procedures for inspecting and replacing the seawater pump impeller.
Explains the function of the siphon break and inspection procedures.
Details the purpose and replacement procedure for the anticorrosion zinc anode.
Provides guidance on simple troubleshooting steps and common problems with corrective actions.
Introduces controller troubleshooting procedures and identifies controller components.
Explains the function of LOP, HET, and HCHT shutdown switches and their effect on engine operation.
Details the controller operation sequence for starting and stopping the generator set.
Provides flowcharts for troubleshooting main control panel and generator set issues.
Emphasizes safety precautions and outlines tests for generator troubleshooting.
Explains the principles of operation for a two-pole, revolving-field alternator with capacitor excitation.
Discusses output voltage and frequency specifications and factors affecting them.
Outlines procedures for testing rotor insulation and continuity.
Details how to test rotor field diodes and varistors for proper function.
Covers testing stator insulation, continuity, and winding resistance.
Explains the process of exciting the alternator after disassembly by applying 12 VDC.
Provides instructions for disconnecting external connections and removing the generator alternator.
Details the steps for reassembling the generator alternator, including torque values.
Covers unique engine disassembly procedures for the marine generator set.
Outlines the procedures for reassembling the generator engine components.
Lists original and maximum limit dimensions for various engine components.
Presents the schematic wiring diagram for the generator set control system.
Shows the point-to-point wiring diagram for the generator set, illustrating connections.