Sterndrives.Com     Mercruiser Sterndrive Information
Mercruiser Parts Mercruiser Help Mercruiser Manuals Mercruiser Tools Mercruiser Sterndrives Contact
My Carburetor Smells Like Varnish

Old fuel will go bad. Really old fuel will turn into "varnish". This varnish will coat the inside of your carburetor and fuel lines. It can also coat the inside of your fuel tank.

An easy way to detect for a varnished fuel system is to sniff with your nose. With the engine OFF, get close to your carburetor and sniff. If it smells like varnish, the carb will have to be rebuilt. Don't even waste your time spraying carb cleaner into the carb, it won't help.

Once a carb is varnished it has to be disassembled and physically scrubbed out. The varnished fuel is stubborn and it clogs the small passages and jets. Running an engine with a varnished carb is very bad. It will cause the engine to run lean and this can cause serious internal cylinder and piston damage.

All it takes for fuel to varnish is about 6 to 8 months of sitting. Temperature and other factors will have an effect on the level of varnishing. Fuel additives can help prevent varnishing but don't do the common mistake and add too much fuel conditioner. Follow the instructions on the bottle.

Once the inside of your fuel tank becomes varnished you have a big problem. The varnished areas along the upper sides and top of the tank can dry up. The dried varnish turns into flakes and these flakes will clog your fuel system. You can hire a Fuel Polishing Company to come out and try to clean out the tank with pressure but they usually charge a minimum of $500.00. Most customers end up replacing the tank.












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.
Sterndrives.Com
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


©2004 Sterndrives.Com •EmailAbout UsHomeReturn Policy Mercruiser HelpShop ManualsSearchContact