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Checking your Carburetor

  You can look up your exact Carburetor or Carburetor Repair Kit  HERE.
  Click HERE for a list of Remanufactured Carburetors.

Engines need the three basics to run. Fuel, Spark and Air.

If you are having engine performance problems and you know you have good spark, you can suspect your fuel system.

Any backfiring may indicate a lean fuel condition such as a clogged carb or restricted fuel supply.

A carburetor can get "varnished" from sitting after a few months. This varnish coats the inside of the float bowl and cloggs the jet passages. It's pretty easy to tell if your carb is varnished. Remove the engine flame arrestor (engine off!) and give the carb a good sniff. If the carburetor smells like varnish it will have to be rebuilt.

Simply spraying carb cleaner into the carb will not fix a varnished carb. It must be completely disassembled, scrubbed clean and reassembled.

If you sniff your carb and you know it hasnt been sitting long enough to varnish, you might have dirt or water in the carb. You might also have a fuel supply problem. Water in the fuel is a very common problem. Remove the fuel filter(s) and dump them into a clean bucket. Look for evidence of water in the fuel. If you find water in the fuel and you suspect that it has gotten into the carb, the carburetor will have to be removed and rebuilt.

Checking the fuel supply is usually done before assuming that the carb needs to be rebuilt. Perform a complete visual inspection of the entire fuel system. Check the hoses, clamps, fittings, pump and pick-up tube. Most fuel tanks have an antisyphon valve installed into the tanks pick-up tube. Read more about checking your antisyphon valve.

Another common carburetor problem is a stuck choke. The choke should be closed when the engine is cold and open when the engine is fully warmed up. Make sure the choke mechanism is free and properly adjusted.

If your engine tends to hesitate when you accelerate, you might have a bad accelerator pump. The accelerator pump is just a rubber piston inside the carburetor that squirts fuel into into throats of the carb while accelerating. If the rubber piston gets worn out it will not supply enough fuel to allow the engine to speed up. Most carburetor repair kits include a new accelerator pump.



Safety
Boats can explode. Moving parts can rip off your fingers. Hot exhaust can burn you to the bone and props can slice you up. One spark near a battery can cause an explosion. You can never be too careful. Remove the battery from the boat before working with fuel. Always disconnect the batteries negative terminal first. Clean up any spilt fuel and let ALL of the fumes dissipate before installing the battery and starting the motor. Pulleys and Belts can grab your clothes and hair. Don't wear loose clothing and keep your hair up under a hat. Always wear safety glasses. Be smart.
Sterndrive-Information
Change your Alpha Gear Lube
Change your Bravo Gear Lube
Why does my drive lube have white streaks?
Why does my drive lube have gray mush?
Replace Your Alpha One Water Pump
Replace your Alpha Gen II Water Pump
Rebuild your Bravo Raw Water Pump

Troubleshoot & Replace your Alpha Shift Cable
Troubleshoot & Replace your Bravo Shift Cable

Replace your Alpha One Bellows & Gimbal Bearing
Replace your Alpha Gen II Bellows & Gimbal bearing
Replace your Bravo Bellows & Gimbal Bearing
Why does my drive "Growl" when I turn?
Water is leaking into my boat from the transom

Replacing your Trim Sender Switches
My Trim doesn't work but my Trailer Switch does
My Trim Gauge is Pegged

Rebuild your Alpha One Upper Driveshaft Housing Assembly
Rebuild your Alpha One Lower Gear Housing Assembly

Check your Engine Alignment
Check for Excessive Steering Play
Troubleshoot an Overheating Problem
Should I remove my thermostat?
Why do I overheat when going fast?
Troubleshoot a No-Crank Condition
Troubleshoot a No-Start Condition
My Engine Backfires and/or Surges and has Lack of Power
What is an Anti-Syphon Valve?
My Engine blows Steam from the Exhaust
Why do I hear a "clakity" sound while at idle?
Exhaust Manifolds...IMPORTANT Information
How do I Winterize my engine?

What is Galvanic Corrosion?
I have a Bravo III Galvanic Corrosion Problem
What is a Mercathode?
All about Zinc Anodes
How do I check my carburetor?
What carburetor do I have? A Rochester or a Mercarb?
I have water in my fuel
My fuel smells like varnish
My fuel is old
My engine has been sitting for several months without being run.

I have a Mercruiser 470, 485, 488, 190, 3.7L Engine
I have coolant dripping from the front of my engine
Can I install a regular Alternator instead of the Stator-Rotor?

Converting an OMC to a Mercruiser


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