Synthetic allows longer periods between changes.
I change every 3K and use 10W30 in the cold months and 20W50 in the warmer months. If your engine leaked after you changed oil, look at the amount you put in. (check the dip stick) Depending on the amount you took out, roughly 3 quarts, then fill to the mark on your dipstick. Gravity effects oil too, so if the oil cap is lose then there is your problem because it all eventually hits the floor. If you did more that just change the oil, (like tightening bolts here and there), well you get the picture. If not, then go to the oil fill cap.
Trouble shooting is a fine art, it normally revolves around what you did last. I know I always start there and normally find that I caused the problem.
Fuel has been a real question over the years. I achieve roughly 38 MPG over the average. Getting better mileage in town if not during peak traffic hours. Driving at freeway speeds keeps my foot on the peddle all the time (and my hand on the horn). I have an oil cooler on my sedan and have found that having an oil cooler has helped to keep my oil cleaner, and using a remote filter gives me the advantage of a better filtering system than was originally offered on the Honda 600.
Some one was talking about tune up's, plugs are a good start, just remember to use a good thread antiseaz compound to keep your threads in good shape. Change the points and condenser, and note the way the blue wire insulation is looking. It tends to shrink right where it bolts up to the points and can cause a short if bare wire is exposed. Often missed is the breaker plate and the advancer assembly. The breaker plate can become lose over the years and not allow the points to maintain their gap. And, the advancer assembly can become tight with crud and not open right. Also, when you tighten the end bolt on the end of the cam use a drop of red lock tight. timing can be set without the engine running. I often use a tach (run a paper clip under the plastic cover where the blue wire connects to the coil. Then just clip your tach/dwell meter positive to the blue wire and black to ground. Then divide like you did with the 8 band 4 cylinder engines. This way you can check the idle speed on Sedans and check the tach on a Coupe.
If your vacuum is low then you may have your timing retarded, if the timing is in the right spot, check compression as you may have ring problems. But if the needle on the indicator drifts between 14 and 16 in. look for spark plug gap not set right and if the plugs are good, the there may be Carburetor adjustments are needed. A leak in the intake manifold will be really low readings, maybe 5 or 6 inches.
Now if your still having problems, and the plugs look good, go to the plug wire connections, and check the engine ground wires. Some people change them and run that negative cable from the battery to the engine, it needs to be attached to the frame also. Original connection point was at the coil mount. This is very important.
Bill
> -----Original Message-----
> From:
> 2cylinderhondas@yahoogroups.com [mailto:2cylinderhondas@yahoogroups.com] > On > Behalf Of > goinhm@...
> Sent:
> Saturday, April 07, 2007 6:50
> PM
> To:
> 2cylinderhondas@yahoogroups.com
> Subject:
> Re:
> [2cylinderhondas] oil leak
> Viscosity is viscosity. 20W50 behaves as 20 weight at 32 degrees F and
> behaves as a 50 weight oil at 200 degrees F. It doesn't matter whether it > is > synthetic or petroleum. So why is synthetic better than petroleum? Here > are > a few reasons:
> 1) with synthetic, all oil molecules can be made
> identically. With
> petroleum, the oil is a blend of molecules of different
> chain lengths. So, a 30
> weight petroleum oil contains long and short
> chains of molecules which
> average out to 30 weight. The longer a molecule
> chain, the weaker it will be to
> shear forces (such as those at the cam
> shaft lobes).
> 2) synthetic oils are far superior at low temperatures
> and can withstand
> higher temperatures. I heard a presentation which
> claimed synthetic oils were
> developed by the Nazis in WWII to solve the
> problem of the oil in their
> equipment (tanks, trucks) caking up during the
> Russian winter when Germany
> attacked Russia. Synthetic oils have been the
> lubricant of choice for years in
> Alaska.
> 3) synthetic oils have
> lower friction. I once saw a demo where a 1967 Ford
> Mustang was running at
> idle and the idle rpm was measured. Then the oil was
> drained and replaced
> with synthetic oil. The idlerpms incresed. Wow, I
> tried it with my Honda
> Z600. My idle rpm stayed the same. Why? The Mustang
> has a bushing-style
> bearing on its crankshaft while the Honda uses a needle
> bearing design.
> The needle bearing design is so much more efficient and one > of the reasons > for using a needle bearing design is to minimize damage if the > bearing is > starved of oil for short durations. The bushing-style bearing > must have > oil and its design suffers if it is starved of oil.
> I suspect the
> culprit in your case may not be the oil as much as the oil > additives. Some > contaminant which was stuck in the engine casing may have > become freed and > found its way to an oil seal where it did some damage. Or the > additive may > have caused an oil seal to swell. Or maybe you just need to > replace the > gasket under your oil cap. Have you tried cleaning off the engine and
> trying to locate where the oil leak is originating?
> Honda never
> recommended using a viscosity above 40 or less than 10 for the > 600 series.
> If you are needing the low numbers of less than 10, then you > must be in a > cold weather climate and synthetic oils would be a better choice.
> If you
> are using above 40 weight, you are introducing more drag which > affects > fuel economy. I have used 10W40 petroleum oil in my Honda cars without
> incident. One time I used Amsoil synthetic oil. One of its claims was not
> needing to change the oil for 20,000 miles. At the time, petroleum oil was > 50 > cents a quart and Amsoil was $5 a quart. I gave up the use of Amsoil at > 10,000 > miles.....I was doing an oil analysis on samples of the oil and it > was > becoming too contaminated with iron, heavy metals, and impurities. I > don't > think the synthetic oil was causing the problem. I think it was a > combination of > the crankcase breathing system letting dusty air into > engine which was > contaminating the oil over time and the crankshaft > bearings were already starting > to fail and I was seeing the early > indicators showing up in my oil about > 10,000 miles before I could hear it.
> In the end, I decided the best way to keep
> the Honda 600 healthy was with
> frequent oil changes rather than trying to
> get long life out of an
> expensive lubricant.
> Dale
> I'm wondering if it is because of the
> type of oil I used.
> Miles told me to use 20W50, but the guy at the
> autoparts store, who seemed
> extremely knowlegeable about oil and engines,
> convinced me to buy a synthetic
> 15W50.
> I exchanged 1/2 quart of oil
> for Slick50. Is it possible this is just due to
> the lighter oil? This all
> started after I changed the oil. I haven't touched
> anything else on the
> engine except the exhaust.
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