26cc 4.5 KWA Marine Engine Thank you for purchasing your new Venom 26cc 4.5 KWA Marine Engine. Not only did you purchase a top of the line R/C Marine Engine but you have also joined the Venom Team and it s world class product line and customer service. Please fully read and understand this instruction manual BEFORE operating this product. Note: This product is not a toy and may cause serious injury if not used properly. VEN-1827
Specifications Basic Engine Specifications: Displacement - 25.4cc Bore x Stroke - 34mm x 28mm Max HP - 4.5@12,500 RPM Idle RPM - 3500 +/- 150 Fuel Type - 87 Octane with Premix 2 Stroke Oil Ignition - Ikeda TDi Carburetion - Walbro WT771 with Primer Pump Net Weight - 2.05kg (w/ Mount) Manual Pull Start Premix Fuel Specifications: Use 90+ Octane Unleaded Gasoline Do not use gasoline with any alcohol or ethanol added Use a high performance 2 Stroke Premix Engine Oil Mix Ratio - 20-25 parts Oil to 1 part Gas (20-25:1) for break-in period, 30:1 standard mixture Engine Operations -The carburetor is tuned from the factory to run but may require an adjustment due to the climate and elevation in your area. -There are three adjustments on the carburetor. The low speed needle, high speed needle and idle screw. High Speed Needle Low Speed Needle Idle Screw - 2 -
Engine Operations Continued -The low speed needle controls the low rpm range of the engine. -The high speed needle controls the high rpm range of the engine. -The idle screw mechanically sets the opening of the carburetor and adjusts the minimum gap for air to pass through the carburetor. In a boat application this setting is often set to the maximum opening. Standard opening of each needle as follows: High Low 1 5/8 + 1/4 1 + 1/4 To start the engine; 1. First be sure the correct fuel mixture has been added and the fuel tank is full. 2. Pump the priming bulb on the carburetor until you see the fuel enter the bulb. 3. Pump the priming bulb 3 more times. 4. Be sure all people and objects are clear of any rotating parts. 5. With one hand, apply firm pressure to hold the top of the engine in place and with the other hand take hold of the pull start T-handle. 6. With a fast deliberate motion, pull the T-handle quickly away from the engine but no further than 10 inches while firmly holding the engine in place. 7. Repeat as necessary until the engine either starts or shows signs of starting. 8. You may adjust the low speed needle, either open or close, to help the engine start but only in small increments of 1/8th of a turn at a time until the engine starts. 9. Repeat step 6 until the engine starts. 10. Once the engine starts return the T-handle to the rest position and remove your hands from the engine and any rotating parts. To shut the engine off press the red shut off button located on the exterior of the model or on the engine itself. It is very important not to over-stress a new engine in the first few running hours of its life. It is highly recommended that the fuel and oil mixture be made slightly more oil rich for optimum lubrication during the first 2-4 hours of operation. In addition, it is also recommended that the engine speed should be limited to about 7000rpm or about half throttle during this time. Please follow the break in schedule below. Initial running - 20:1 fuel ratio for 1hr 25:1 fuel ratio for 3hrs 30:1 fuel ratio for standard operation The engine will continue to improve in performance and will continue to break in for a short time following the initial 4hrs of operation. - 3 -
Tuning Guide There are three basic areas of adjustment on a gasoline 2 stroke engine: 1. Carburetor 2. Spark Plug 3. Gasoline to Oil Ratio Carburetor Tuning While the engine is running at idle speed you can adjust the Low Speed Needle to set a steady low RPM idle. When the engine speed is at its maximum RPM the High Speed Needle is used to adjust the optimum top speed performance. The goal is to try to tune the engine until there is smooth transition from low to high speed and back to idle with out any interruptions. To set the High Speed Needle while the engine is running there are two steps. 1. Once the engine is warmed up set the engine to full open throttle and adjust the High Speed Needle until the engine sound is clear and smooth. Now place the needle setting to 1/8th to 1/4th turn rich (Counter Clockwise, CCW). Do this within 30 seconds and allow the engine to return to idle. Monitor the engine temperature during this step. 2. Step 1 above is done without a load on the engine to get an initial setting. Now run the engine in the model and set the throttle to full open. The engine should run smooth and with full power. If not, readjust the High Speed Needle until you hear a smooth crisp exhaust note. This will be the maximum performance setting for that particular day and will require fine tuning depending on climate and location from day to day. NOTE: Always pay close attention to the engine temperature when tuning on the bench and in normal use. Maximum Operating Temperature - 250F Optimal Engine Head Temperature Range - 210-230F max Maximum Engine Head Water Temperature - 212F Pro Tuner Tip Use a small aquarium water pump, extra silicone tubing and a bucket of cold tap water to keep the engine and exhaust pipe cool while testing and breaking in a new engine. The Idle Screw will set the mechanical travel of the carburetor butterfly valve which controls engine speed and response. Setting the Idle Screw and the Low Speed Needle together will control the low speed idle range of the engine. In a boat application when a clutch is not installed on the engine a higher Idle Screw setting is required and it is common for this to be adjusted to the maximum setting. Use the Low Speed Needle to make idle speed adjustments in this case. Factory Needle Settings High Speed Needle - 1 5/8 turns from closed Low Speed Needle - 1 turn from closed CCW (Counter Clockwise) = Richer mixture CW (Clockwise) = Leaner mixture (Does not apply to the Idle Screw) - 4 -
Tuning Guide Continued NOTE: Never over tighten the tuning needles when adjusting. This will cause damage and poor tuning ability. Spark Plug Tuning There are a few performance gains from understanding and tuning the spark plug of a gasoline engine. The basic areas of interest are the Air Gap and Color of the spark plug used. Spark Plug Air Gap - the distance between the outer electrode and inner electrode. The main issues with spark plug gaps are: narrow-gap risk: spark might be too weak/small to ignite fuel narrow-gap benefit: plug always fires on each cycle wide-gap risk: plug might not fire, or miss at high speeds wide-gap benefit: spark is strong for a clean burn A properly gapped plug will be wide enough to burn hot, but not so wide that it skips or misses at high speeds, causing that cylinder to drag, or the engine to begin to rattle. Standard Spark Plug Gap - 0.6-0.7mm / 0.023-0.0275in Reading the Color of the Spark Plug Normal Operating Color - exterior electrode has a very light tan color, resembles ash, the interior electrode has a clean brown color, no deposits on any surfaces. Dry or Wet Fouling - the overall appearance of the plug is black and sooty or very wet with an oily appearance. Over Heating - The plug end will appear glazed especially around the ceramic insulator Replace wet, fouled, or damaged spark plugs and try to determine the cause of the fouling. Its ok to clean a spark plug if a replacement is not available but for optimum performance the fouled plug should be replaced. The color of the plug will indicate the operating condition of the engine internally. Adjusting the carburetor and using the correct fuel mixture will usually correct the problem. Gasoline to Oil Ratios The two stroke engine relies on a delicate mixture of oil mixed in with the gasoline in order to perform at maximum performance levels. Since the oil which lubricates the engine is mixed in with the fuel it is possible to cause severe engine damage and total failure if the mixture is incorrect. Please follow these guidelines to ensure proper performance and good engine life. Fuel Ratios 20:1 Initial running - 1hr 25:1 3hrs 30:1 Standard operation 32:1 Only recommended for experienced tuners How to read the ratio of gasoline to oil: The ratio above is related to 1 US Gallon of gasoline. The more rich the ratio the closer the relationship of gasoline to oil is 1 part to 1 part (1:1). The number on the left is the amount of gasoline used. The number on the right is the amount of oil. The smaller the gasoline number, the more rich the mixture will be because there is more oil in relation to gasoline. Use high performance 2 Cycle Premix Oils that contain Castor Oil and Synthetic Lubricants commonly found at Motorcycle Dealerships, Go-Karting suppliers, Gardening and Power Tool Supply stores. Use a proper oil ratio measuring cup or container. - 5 -
Recommendations Exhaust Recommendations The Venom 26cc 4.5 KWA Marine Engine can accept a whole range of exhaust systems from tuned exhausts to silencers and various manifolds. Choose the exhaust system according to your application and follow the exhaust manufacturer s recommendations for tuning and performance guidelines. Exhaust Port Bolt Pattern - 34mm center to center, M5 thread Basic Exhaust Port Dimension - 20.6mm x 11.5mm Propeller Recommendations The Venom 26cc 4.5 KWA Marine Engine will perform with a range of propellers for gas boats. The Hull design, weight and drive system will have a great influence on the choice of an optimal propeller. Some experimentation will be required to obtain the best performance possible. Propeller Diameter range - 65-75mm Pitch Ratio range - 1.4-1.9mm Pro Tuner Tip Experiment with multiple blade counts and pitch ratios for different conditions. A 3 blade prop will help in choppy conditions and with acceleration from corners. A two blade prop is the most efficient and will usually achieve the highest speeds, but it is sensitive to water conditions. Changing the pitch ratio will change the rpm of the engine and will have different performance benefits. Listen to the engine sound, aka note, when experimenting with propellers to find the best performance. A crisp clean sound should resonate from the engine when at full power with the correct prop. Use a GPS handheld unit mounted in the boat to compare speeds between set ups. - 6 -
Trouble Shooting Engine Does Not Start - No spark in spark plug Description Cause Fix Spark Plug 1. Wet Spark Plug Electrode Dry Electrode 2. Carbon Deposits On The Electrode Clean Spark Plug 3. Spark Plug Insulator Damage Replace Spark Plug 4. Improper Spark Gap Adjust To 0.6-0.7mm 5. Burned Out Electrode Replace Spark Plug Magneto 1. Ignition Coil Inside Failure Replace Spark Plug 2. Damaged Cable Sheath or Disconnected Cable Replace Or Repair Switch 1. Switch Is Off Turn On Switch 2. Switch Failure Replace Switch 3. Primary Wiring Is Grounded Repair Engine Does Not Start - Sparks appear in the spark plug Description Cause Fix 1. Too much Fuel In Engine Drain Excess Fuel from Engine Compression & Fueling Is 2. Fuel too Rich Adjust Carburetor Normal 3. Flooded Carb Adjust Carburetor or Replace 4. Poor Fuel Quality Exchange with Proper Fuel Fueling Normal 1. Worn Out Cylinder, Piston, or Piston Ring Replace Cylinder & Piston Set But Poor Compression 2. Gas Leakage from Cylinder & Crank Case Gasket Apply Liquid Gasket & Reassemble 1. Choked Breather Air Hole Clean Breather No Fuel 2. Clogged Carburetor Clean Carburetor Supply 3. Fuel Lines Improperly Installed Check Fuel Lines Lack of Power or Poor Performance Description Cause Fix 1. Air Leak in Fuel System Check Connections Compression Is Normal w/ 2. Air Leak at Intake Tube Joint or Carburetor Joint Replace Gasket or Tighten Screws No Misfire 3. Water in Fuel Replace Fuel 4. Piston Seized Replace Piston & Cylinder 5. Muffler has Excessive Carbon Build-up Clean Muffler Overheating 1. Carburetor Set too Lean Adjust Carburetor 2. Poor Fuel Quality Replace Fuel 3. Excessive Carbon Build-Up in the Combustion Chamber Clean Combustion Chamber 4. Spark Plug Electrode Red Hot Thoroughly Clean, Adjust Spark Gap [0.6-0.7(0.023-0.028in)] Others 1. Over Loading Reduce Load - 7 -
Warranty VENOM LIMITED WARRANTY: Venom warrants this product to be free of material and workmanship defects when new. If a component is defective or was not correctly made, Venom will, at its sole discretion, repair or replace it free of charge within 90 days from date of purchase. If you believe a defect became evident only after operation, please contact us to discuss the situation. A dated and itemized sales receipt must accompany any product returned for warranty work. Before returning any product, please contact Venom Customer Service at 800-705-0620 to receive a Return Merchandise Authorization Number (RMA#). GUARANTEE: We guarantee this product to be free of manufacturing faults and material defects. This product has been checked and adjusted individually before leaving the manufacturer. Please contact your local retailer for replacement parts and technical support or contact Venom Customer Service at 800.705.0620 or customerservice@venom-group.com. Copyright 2008 by Venom Warning WARNING: This product is not a toy. It is not recommended for children under 14 years. Minors should be accompanied by an adult when using. This product is a precision machine that requires proper assembly and setup to avoid accidents. Failure to take caution when operating this product may result in serious injury or property damage. It is the owner s responsibility to operate this product in a safe manner. Venom and its affiliates, successors, heirs, and assigns are not responsible in any way for any and all bodily injury(s) and/or property damage that may occur from the use of or caused by in any way this product or its parts. CALIFORNIA PROPOSITION 65 HEALTH RISK WARNING: This product contains a chemical or chemicals known to the state of California to cause cancer, birth defects, or other reproductive harm. This (these) chemical(s) may be harmful to your health. Do not place hands in mouth after handling this product. Do not place this product in mouth. Wash hands with soap and water immediately after handling this product. - 8 -
Parts List 1849 1841 1839 1830 1833 1832 1835 1831 1838 1834 1837 1836 1842 1829 1847 1845 1843 1846 1848 1834 1848 1837 1836 1844 1829 1828 VEN-1828 Crankcase Assembly - KWA VEN-1829 Crank Shaft Assembly - KWA VEN-1830 26cc Cylinder - KWA VEN-1831 Cylinder Gasket - KWA VEN-1832 26cc Piston - KWA VEN-1833 Piston Ring VEN-1834 Piston Pin VEN-1835 Snap Ring VEN-1836 Positioning Washer VEN-1837 Need Bearing VEN-1838 Intake Gasket VEN-1839 Bolt (M5*25) - KWA VEN-1840 Exhaust Gasket - KWA VEN-1841 Water Jacket - KWA VEN-1842 Carburetor VEN-1843 Recoil Assembly VEN-1844 Flywheel - KWA VEN-1845 Ignition Coil -KWA VEN-1846 Kill Switch Set - KWA VEN-1847 Frame Set - KWA VEN-1848 Mount Assembly - KWA VEN-1849 Spark Plug - 9 -
Notes
Customer Service 800.705.0620 customerservice@venom-group.com www.venom-group.com Venom Group International United States of America 600 West Buckles Road Hayden, ID 83835 Australia P.O. Box 7325 Alexandria NSW 2015, Australia