
Oscar Zerk invented the zerk fitting for grease guns.
|
how to work on your own outboard motor:
Contrary to popular opinion, it's easy for do-it-yourselfers to do the basic outboard motor repairs, including changing engine oil and filter, gear case oil, and sparkplugs.
Sometimes if you ask for a parts discount, based on the fact you are a do it yourself, you get it. Sometimes you don‘t. Don’t make the mistake of skimping on oil quality. Four-stroke sumps hold a minimal volume of oil. Engine loads are high. Contrary to a car engines life cycle, outboards never coast down a hill. Combustion heat is like a mini refinery, boiling off lighter oil molecular and sapping additives of their strength. Combustion by-products dirty the oil. The older the oil, which is to say the more engine hours logged, the less efficient it is.
For the same reasons as crankcase oil, a new engine’s gear oil is meant to be changed after the first 20 hours of operation. But don't rush in. First, get your hands on a long shank screwdriver. The extra leverage make it easier to wrestle out a stubborn screw plug
Crack the lower drain plug just enough so that whatever liquid is inside trickles out. Take note of what you see, then remove the top plugs and then but bottom remove the plug entirely, draining the contents into a catch pan. Water, even a couple of drops, is a bad omen, so too is chocolate color. Water intrusion happens when fish line wraps around the propeller shaft then burrows inward, cutting the shaft seal. Whirling gears pressurize the oil, forcing it out through the damaged seal. When the engine shuts down, the missing oil leaves a vacuum. The vacuum sucks in water. Unfortunately as little as an ounce of water can destroy a gear set. The only remedy is to replace the seals, usually a job for a pro.
If instead of water, you catch a whiff of burned oil, that too portends evil. Take a finger full of oil and sniff. Rub the oil between your fingers noting whether it feels gritty. Look in oil drain pan for broken bits of steel or bronze. Some techs poke a magnet into the drained oil to see if it will attract small bits of ferrous gear metal.
|
Now remove the engine cowling. Replace the on-the-engine fuel filter about every 100 hours. Common wire ties work great for hose clamps. Go wide, not narrow, for optimal goodness of fit.
What about a sparkplug change? Gapless sparkplugs are plug-and-play easy. Right out of the box they’re ready for installation. Just be careful not to over tighten them, otherwise you risk the complication of stripped threads. Classic side gap sparkplugs are often preset. But be sure to double check the electrode to side gap clearance with a gaping tool. Owners manuals specify a range, say from 35 to 40 thousandths of an inch (.034 - .040).
Savvy marine engine technicians adjust spark plug gap closer to the smaller number for the simple reason as an engine logs hours its sparkplug gap widens (Roughly .001 every 20 hours). A tighter initial gap means the engine stays in tune longer. For example, assuming 100 hours per season, an engine tuned with .040 plugs would be ready for a tune-up by the end of the summer, while an .035 engine would be good for another year.
Battery posts, terminals and cables must be bright and shiny clean. Otherwise, green, gritty, corrosion bottlenecks outbound current flow to the starter motor and electronics plus resisting inbound charging from the engine alternator. A dedicated post and terminal tool with its male and female wire brushes gets the job done quicker than the time it takes to explain it. Clean the battery top with a solution of baking soda and water, being careful not to let any get into the cells.
Fuel injected engines benefit from an additional canned cure. Wax build-up on the injector nozzles cause fuel to dribble instead of mist. The fix, dose the fuel with injector cleaner, or a tankful of high octane gas. You’re not buying octane, you’re buying a superior additive package that unplugs fuel injectors and scrubs carbon from the combustion chamber. With either method, the before and after difference is dramatic.
Finally, no matter which canned cure is prescribed, it’s vital to read the label on the can and strictly follow directions. Protect fingers and eyes with gloves and goggles.
© Copyright 2007 by Tim Banse |