Chapter M-2's Technical Corner

Howard Halasz's September 2009 Technical Article


" T-CLOCK PART ‘O’ - OILS, FUELS, FLUIDS, & LUBRICANTS "

T-CLOCK INSPECTION

Our continuing T-CLOCK discussion for this month is about the letter O for Oil. We'll also discuss other fluids such as hypoid gear oil, hydraulic fluid, coolant, and fuel.

Let's talk about engine oil first. If your motorcycle has a center stand, I recommend that you put the motorcycle on the center stand. If you have no center stand, have someone hold the motorcycle level on level ground. If the engine is cold, the oil level should appear at the full mark in the sight glass or dipstick. Remove the dipstick; wipe it off with a shop towel, and stick it in the dipstick hole, but do not screw it in. Remove it and check the oil level. If the engine is cold, the level should be at the full mark. If the engine is warm, the level might be between the half and full mark. This is normal, because a warm or hot engine may not have had enough time to allow the oil to drain down into the crankcase.

Now let's try to answer that age old question about "which oil should I use" and "which gas should I use?"

According to my 1994 Honda Gold Wing Owner's Manual, we should use PRO HONDA HP4 4-STROKE OIL OR AN EQUIVALENT. For Canada: USE HONDA 4-STROKE OIL OR AN EQUIVALENT. Use only high detergent, premium quality motor oil certified to meet US automobile manufacturer's requirements for Service Classification SF or SG. Motor oils intended for Service SF or SG will show this designation on the container. THE USE OF SPECIAL OIL ADDITIVES IS UNNECESSARY AND WILL ONLY INCREASE OPERATING EXPENSES!! Engine oil is a major factor affecting the performance and service life of the engine. Non-detergent, vegetable or castors based racing oils are NOT RECOMMENDED. Honda's recommended oil viscosity is SAE 10W-40. SAE 20W-50 and SAE 20W-40 may be used when the average riding temperature is above 35° F. SAE 10W-40 may be used when the average riding temperature is above 8° F. SAE 10W-30 may be used when the average riding temperature is between 8° F. and 90° F.

Here's what my 1994 Honda Gold Wing Owner’s Manual says about what gasoline to use: Your Gold Wing engine is designed to use any gasoline that has a pump octane number 86 or higher. Gasoline pumps at service stations normally display the pump octane number. Honda recommends that you use unleaded fuel because it produces fewer engine and spark plug deposits and extends the life of exhaust system components. Never use stale or contaminated gasoline or an oil/gasoline mixture. Avoid getting dirt, or water in the fuel tank. Use of too low of an octane gasoline can cause persistent "pinging" or heavy "spark knock" (a metallic rapping noise) which, if severe, can lead to engine damage. Use of too high of an octane gasoline can increase operating costs and cause you to get poor performance and poor fuel economy, contrary to popular belief. If "pinging" or heavy "spark knock" occurs at a steady engine speed under normal load, Honda recommends changing brands of gasoline. If the "pinging" or heavy "spark knock" persists, you really need to consult your authorized Honda dealer. Failure to do so is considered misuse by Honda, and Honda's Limited Warranty does not cover damage caused by misuse.

Refer to your owner's manual maintenance schedule to check your hypoid gear oil. Gold Wings use hypoid gear oil in the final drive unit. While the Gold Wing is on the center stand, unscrew the large filler plug. Stick your finger in the hole to check the level. If the level is about one-eighth inch below the bottom of the hole, you may need to top it off. Also check the color of the oil. It should look and feel like honey. If it's black or dark brown and smells like sewer gas, it's probably time to change the oil. Remove the drain plug and allow at least half an hour for the oil to drain. Replace the drain plug and refill with fresh hypoid gear oil. The final drive case has enough oil when the oil starts to run out of the lower part of the filler hole. Replace the filler cap.

Hydraulic fluids such as brake fluid should be changed if it looks like black coffee or strong tea. If the clutch master cylinder reservoir fluid level appears low, top it off, being careful not to spill any fluid on any painted or plastic surfaces if you are using DOT 3 or DOT 4 fluid. If you're using DOT 5, you need not be as careful because DOT 5 hydraulic fluid is not destructive to paint and plastic. We recommend that you do NOT use DOT 5 and use only what Honda recommends in your owner’s manual. If you ride a 1975-1979 Gold Wing, your owner’s manual will recommend DOT 3 only because DOT 4 was not on the market when the GL1000 Gold Wings were current. Stu Oltman, WING WORLD’s Senior Technical Editor recommends using DOT 4 brake fluid in all Honda Gold Wings, 1975 to present year models

Before you even think about topping off your brake master cylinder reservoirs, check the thickness of your brake pads. If the pads are worn beyond their wear marks, replace them. When you compress the pistons into the calipers, the fluid levels in the reservoirs should return to normal levels. If the levels still appear low, it's best to top them off only with new brake pads in the calipers.

Check the coolant level in the coolant recovery tank when the engine is stone cold. The level should appear between the half and full mark. If you check it when the engine is hot, you might not get an accurate reading.

Check for engine oil leaks at gaskets, housings, and seals. If the leaks seem excessive, replace the gaskets or seals. Check for seepage at the dipstick, final drive breather, drain plugs, and filler plugs. If the seepage is excessive, replace the O-rings. Check for leakage at the shift spindle seal. Replace the seal if necessary. By the way, shift spindle seal replacement is no job for a shade-tree mechanic on the six-cylinder Gold Wings. See a certified Honda tech to make sure the job is done right the first time.

If you can smell coolant after your engine warms up, but see no signs of leakage, there is a coolant leak somewhere. The coolant might be evaporating after it seeps out and hits a hot engine surface, thus the strong smell of antifreeze. See a certified Honda tech for diagnosis and repair. The most common of these hidden leaks appear at the upper radiator hoses and the carburetor heat riser hose connections on the GL1500s.

If you can smell gasoline after your engine warms up, but see no signs of leakage, open your fuel filler door and look for signs of leakage at the filler cap and the vacuum operated fuel cutoff valve if your Gold Wing has a vacuum operated fuel cutoff valve. Replace the faulty components. If you have doubts, see your authorized Honda service technician. Fuel leaks and strong fuel smells coming from anywhere on your Gold Wing could lead to some serious and expensive fire damage repair.

Howard Halasz, Technical Coordinator

GWRRA Spring, Texas Chapter M-2