How Do I Adjust The Valves?2024-02-16T08:57:18-06:00

Remove the valve cover.

Remove the spark plug, put finger on plug hole and turn over the engine until you feel the compression stroke air pressure.

Turn the flywheel to close both valves.

Insert a narrow screwdriver into the spark plug hole and touch the piston. Turn the flywheel clockwise past top dead center until the piston has moved down 1/4″. Use the screwdriver to gauge the piston’s range of motion. PLEASE NOTE: This procedure must be performed for each cylinder on V-Twin engines.

Check the valve clearance by placing a feeler gauge between the valve head and the rocker arm. Clearances differ for the two valves and typically range from .002 – .004″ to .005 – .007″. Valve clearance specifications for your engine series are available by viewing our Engine Specifications Chart (pdf).

Adjust the clearances as required by turning the rocker screw. Once adjustments are completed, tighten the rocker nut.

Install the valve cover, using new gaskets, as required, and make sure the cover is secure.

I Have Excessive Vibration, Loose Bolts, Cracks & Gaskets Leaking2024-02-16T08:57:00-06:00

The one most single thing you can do to prevent your motor from shaking to pieces, loose bolts, cracks and gasket leaks is to ensure your propeller is not worn, bent or out of balance. If so, replace it immediately. Check by revving the engine to full throttle in a safe manner. Observe the skeg and front of the engine. If it begins to vibrate excessively after 2500 rpm, and especially at 4300 rpm, change the propeller immediately.

My Engine Stalls At Idle, Or Cuts Out At High Speeds2024-02-16T08:56:42-06:00

Several basic items should be checked. First, is the fuel tank full of fuel and vent open? Water in fuel or excessive amounts in water separator? Your engine should idle between 1250 and 1450 for stock motors and 1000 to 1200 for Mikuni aftermarket engines.

Is the fuel line pinched from a heavy object sitting on the line, or is a tight connection restricting flow? Are there cracks in the line or connections, allowing air to leak into the fuel system? If you placed your fuel tank near the front of the boat, did you use a recommended 5/16” or 3/8” fuel line? If you added a quick disconnect to the fuel tank, especially OMC type, you may be restricting fuel.

Do you have rope, weeds or wire wrapped around your propeller? Is your fuel filter dirty or plugged? Is your engine oil low?

Tip: If you use an in-line primer bulb, do not over pump the Mikuni carburetor aftermarket engines. These carburetors have very small needle and seat valves and if you over-pump the bulb, you can push small particles of debris past the fuel filter element and into the needle and seat where it will plug the carburetor. This can stop the engine or restrict fuel during acceleration or at full throttle.

Also, the Mikuni carburetors have a low speed idle jet on the side of the carburetor. (brass screw). If your motor experiences hesitation at throttle-up, turn the screw in. The idle screw is normally set at 1 and a half turns out, but it can be run as far as all the way in. Each engine and carburetor are slightly different.

If you are in a state that is using 10% ethanol and you aren’t using our fuel tank and new fuel lines, the ethanol can deteriorate the older system and cause particles to enter the fuel system, plug up fuel filter, etc.

What Gear Ratio Should I Use?2024-02-16T08:56:24-06:00

We are proud to say that we are the only manufacturer that offers a wide selection of motors, drives, engines, performance components and gear sets. In order to get the best forward motion from your engine, whether stock or modified, light or heavy boat, sea level or high altitude you need the correct gear ratio.

Here is the recommended gear set for our short tail models:

14 and 18 Vanguard – 28 to 32 tooth top sprocket and 50 tooth bottom sprocket. (1:1.471 gear ratio) These models have low power and are sensitive to loads. So we gear them according to customer need.

23 Vanguard – 34 tooth top clutch/sprocket and 50 tooth bottom sprocket. (1:1.471 gear ratio) On some models we put a 52 tooth on the bottom for more low end power.

27 Kohler, 29 & 31 Vanguard – 36 top and 50 bottom (1:1.389 ratio). On some models, we put a 52 tooth on the bottom or 34 tooth on top for more low-end power.

35 Vanguard – 38 top and 50 bottom (1:1.316 ratio)

HD 4000 – 38 top and 49 bottom (1:1.289 ratio) HD 4400 – 38 top and 49 bottom (1:1.289 ratio) HD 45 Mag – 38 top and 48 bottom (1:1.263 ratio) HD 5000 – 38 top and 48 bottom (1:1.263 ratio) HD 6000 – 38 top and 46 bottom (1:1.210 ratio) HD 7000 – 40 top and 46 bottom (1:1.15 ratio) Black death 4500 – 38 top 48 bottom (1:1.263) Black death 5500 – 38 top 46 bottom (1:1.210)

If you hit the rev limiter, go to the 40 top.

Comments: If the customer has a large load, we would decrease the top sprocket by two teeth or add two teeth to the lower sprocket. This causes the engine to spin faster/prop to spin slower for more bottom end power. When the motor is new, it is easy/no expense to change the top sprocket/clutch ratio. Afterwards it is easier and less expensive to just change the lower sprocket size.

Performance Engines: When a customer adds power to his engine we use the above chart to change the gear ratio. Small 100 to 150 rpm changes can be made with one tooth changes such as our 47 and 49 tooth sprockets. Only a few of us use these.

Load: When a customer changes boat and/or increases load we make small adjustments by increasing the size of the lower sprocket by two teeth. Example, increase from 50 to 52 teeth will add 100 to 150 rpm. This can be done on all models except the mini 23 and 27 because the largest lower sprocket that will fit in the outdrive is 50 tooth.

All our lower sprockets are aluminum with an anodized hardened finish. They are interchangeable between Hyper, Sport, Hunter, Lite and Mini models by use of a mounting bushing. Specify when ordering the Hyper busing which has (7/8″ drive) or the Sport/Hunter/Lite (25MM) drive shaft size. The cost of replacement sprockets is about $85 plus shipping.

What Spark Plugs Should I Use?2024-02-16T08:55:57-06:00

Our large block Vanguard engines come with a Champion RC12YC spark plug.

Although the gap can vary from .030 to .040 on new motors, they should be at .035. We have found that the AP3923 spark plug is a good upgrade. It is an Autolite Platinum plug and comes in AP and APP -the later being double platinum and lasts longer. It is a slightly cooler plug and although the details regarding why we use this are long, we like to use this plug on performance motors and/or when replacement time comes.

Don’t underestimate the value of having fresh and well performing spark plugs. For starting, acceleration and top speed – good plugs, produce good results. They are the heart of your engine.

How And Why Should I Register My Motor?2024-02-23T12:20:37-06:00

It is very important to register your motor. Not only does it allow us to keep you informed of any recalls and other important information about your motor, but it also helps us help you in regards to your warranty and helping you with any repairs that may be needed. It is an easy process to register your motor, click here to get started.

How Do I Find a Dealer?2024-02-23T12:21:57-06:00

To find your closest dealer, follow this link to our dealer locator and enter your zip code. You can sort your search by Mud Buddy only or add in Service Centers and Excel Boats dealers.

Is My Motor Still Under Warranty?2024-02-16T08:52:08-06:00

Depending on the motor you purchased and the date it was purchased on, your warranty will go into effect. Contact customer service on the about page if you have questions about the length and terms of your warranty.

Where Do I Buy Performance Parts?2024-02-27T11:06:06-06:00

Performance parts and repair parts can easily be purchased from Backwater Performance Systems. They are continually creating cutting edge performance upgrades for our motors as well as providing a wealth of knowledge to help you get the absolute best performance from your motor.

Where Is Mud Buddy Motors Located?2024-02-16T08:48:53-06:00

Mud Buddy Motors is located in West Jordan, Utah, just south of the Great Salt Lake. We have been manufacturing motors here for 25 years. 7956 S. 1530 W., West Jordan, Utah 84088 | (385) 247-1970

Who Do I Contact For Issues With My Motor?2024-02-23T12:24:14-06:00

If you are having trouble with your motor, please contact our customer service department as soon as possible. You can click the chat box located on the bottom right-hand corner of this and all pages. Or, you can send an email directly to keith@mudbuddy.com. We strive to respond to your questions as quickly as we are able. Here are few tips that will help us help you.

  1. Have your motor registered with the company. If you didn’t do this when you bought your motor, it is not too late. Click Here to register your motor
  2. Have your serial number at hand, as well as the model, and year it was purchased.
  3. Know the location of where the motor was purchased.
Can I Run In Salt Water?2024-02-16T08:30:38-06:00

Mud motor engines are not designed to run in salt water, so we need to ensure these suggestions are followed if you run in this type of environment. We recommend that you flush the outside of the motor and drive every time you exit salt water. Run the engine at idle and slowly inject a water flow into the flywheel so that the mist will wash off the coils and wires under the engine cowl. If you keep your boat moored in the water, always tilt the outboard so the gear case is completely out of the water (except in freezing temperature) when not in use. Add a corrosion control anode to the boat side of the skeg. Any small configuration works. Each month, spray Mercury Precision Lubricants or Quicksilver Marine Lubricants Corrosion Guard on external metal surfaces and on all exposed wire connections and harnesses. (DO NOT spray on corrosion control anodes as this will reduce the effectiveness of the anodes). If you power-wash the mud motor, do not spray the high pressure into wire harnesses or near oil seal areas. Paint chips should be sanded lightly and re-finished to avoid corrosion.

Can I Run My Engine Out Of The Water?2024-02-16T08:30:16-06:00

Yes, but be careful around other people and pets, and do not engage the drive longer than five minutes. The patented Mud Buddy seal system uses a special configuration of seals that prevents the outer most seal from being lubricated other than when running in water. If for some reason you need to run the drive longer than five minutes outside the water, remove the propeller and spray oil or silicone on the outer seal. WARNING! as smart as our hunting dogs and children are, they will walk right into a blurred spinning propeller. Always use extreme caution.

How Do I “Break In” My Engine?2024-02-16T08:28:59-06:00

Break-in is important to ensure correct engine performance and life. Even though many of us have stated in the forum that you can run the engine at full throttle after five minutes, the official answer is to follow the procedure listed in the Engine Operation, Maintenance and Warranty Manual which usually states don’t run at full throttle for the first 2 hours, then only briefly until 5 hours and always vary the throttle level during operation the first ten hours.

Generally, for the first two hours, we recommend avoiding extended idling, sustained periods of wide open throttle, or holding the engine at one speed for extended periods of time.

Use 87 or higher octane, 91 or higher for the performance engines.

Change your oil, lubricate all drive points and check the belt tension at 20 hours. This is the single most important thing you can do for your engine and drive.

How Do I Know When My Propeller Is Worn Out?2024-02-16T08:28:54-06:00

Your propeller is affected by wear. You will see decreased acceleration, poor hole shots, inability to carry a large load and your speed will decrease. Check your propeller by measuring the outside distance, diameter of the propeller. If you are running a 12 X 10 Big Blade, for example, the 12 is the diameter and the 10 is the pitch or angle of the blade. If you measure the propeller and it has 1/4″ or more decrease in diameter, then replace the blade.

How Do I Protect My Engine In Freezing Temperatures?2024-02-16T08:28:48-06:00

Mooring and Hunting – When moored in freezing or near freezing temperature, keep the mud motor tilted down at all times so the lower outdrive is submerged. When you park your boat overnight and during hunting, park in a location where the waves are not splashing against the engine. This will cause severe ice build up on the outdrive and trim assembly. This can prevent your motor from turning and trim can freeze in position. If this happens, don’t hammer the ice off the trim unit since this can break the wires and seal surfaces.

Belt Housing Leaks – Check your belt housing for water and condensation before freezing weather arrives by removing the small drain screw from the bottom of your belt housing. If there are more than a few teaspoons of water in the drive check for seal leaks. Tighten all the front and rear outdrive bolts. In some cases, you can remove the clutch cover or vent inlet and fill the belt housing with water. You will then see the leak location. Seal threads and surfaces with an automotive sensor safe silicone (alcohol based available at auto parts stores). Do not use household window and door silicone sealer (they are ammonia based and will corrode the surfaces and wires).

Throttle Cable – If any water enters the throttle cable it will freeze and prevent you from running your motor. If you thaw out the cable with your hands or some other type of heat, I guarantee it will freeze when you are driving and you will have an unpleasant surprise. The throttle will stick and you will need to turn the key off or use the safety kill switch to stop. On short transom boats, the sudden stop will cause a wave to come over the transom. This is unsafe.

Prevent water from entering the cable by elevating both ends all the time. We elevate the engine side cable and you need to elevate the throttle end when you receive and install the handle on new motors. Use a tight wire tie 6″ from handle to elevate the cable slightly.

Remove water in the throttle cable by removing the cable, hanging it vertically and insert WD-40 or silicone spray. The best way is to slide a tight fitting rubber hose over the throttle cable and spray silicone into a container and us the hose to funnel silicone into the throttle until it runs out the lower end. Now install the cable with both ends elevated.

Cover the throttle and handle controls with a plastic bag in freezing rain. The ice will build up and cause the switches to freeze in place. If you hammer the ice from the switches this can cause breakage. Carry a zip-lock, cover, or handle cover when in these freezing rain conditions.

Protect your fuel by removing ice and snow from your fuel tank. Shine a flashlight into the fuel tank at night and the little diamonds floating in the bottom of the fuel tank are water droplets. Don’t allow ice and snow to enter the tank when refueling. Use moisture dissipating fuel additives in cold weather. One small ice particle in the tank, fuel line, filter or carb will make for a very short or long day on the water.

Carb Freezing can occur when running on mist or foggy water when temperatures fall below 35 degrees, not 32, 35 degrees. The accelerated damp air moving through the intake system will cause a sudden temperature drop and ice will build up in your carburetor. This will cause loss of power, exhaust smoking, accelerated fuel consumption and a headache. We make many models of engines and the Kohler, Kawasaki and large Vanguard have cold weather icing problems. On all these motors, turn the air filter intake towards the exhaust so warm air enters the motor. If your engine intake freezes, shut off the warm engine and cover with a motor cover, decoy bag, jacket or anything to keep the engine heat on the carburetor. It will thaw out in 10 minutes.

Parking a boat on steep snow covered shorelines can be dangerous. Approach a snow covered bank slowly. The boat will power up the snow covered shoreline easily and when it slides back into the water, the transom can submerge.

Snow and ice are the boat and motor’s worst enemy. Cover your boat and motor when not in use. When the boat and motor become full of snow and ice builds up, it is necessary to garage the boat and completely thaw out all the components. Ice builds rapidly in the boat, adds weight and affects the stability and safe operations of the boat. Ice covered wires easily break. We have lots of fun when the weather gets very cold, but preventative maintenance is imperative.

What Oil Should I Use And How Often Should I Change It?2024-02-16T08:28:43-06:00

You can use regular automotive, synthetic or synthetic blend oil during break-in. 10W30 is best. We say use the best oil you can buy. It protects your engine, the engine runs faster and longer. Oil should be changed every 25 to 50 hours.

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