vfm@ihu1f.UUCP (09/01/83)
In response to Carl, U.C. San Diego:
I'm not sure what "film" other than varnish or sludge that may form
from petroleum oil use. All the test results I have read do not
reveal any "invisible" film. There is a test for film/shear
strength, this ASTM (Automotive Society of Testing Methods)
(federal government) test procedure is performed by putting a
lubricant between two pieces of metal and seeing how much pressure
it takes to squeeze it out. The best conventional petroleum oils
run 400 - 700 psi, synthetics ~3200 psi, yes, 3200! As far as
"rattling around" goes (?), my only suggestion is don't use a 5W-XX
(Mobil 1) weight lubricant. I would recommend a 10W-40 or 20W-50
racing synthetic (AMSOIL has both). These products are used by
many bike riders (Harleys to Hondas), including those with wet
clutches. Although "slipperier" the coefficient of friction of
them will not cause a properly adjusted, good clutch to slip.
Fred Eklow, manager/chairman of BI Wheel Express, a motorcycle
courier service in Cincinnati switched his 4-cycle Suzukis to
AMSOIL. Since the switch he noticed "improvements in operating
temperatures, fewer repairs, better gas MPG and improved life of
internal parts".
Oil consumption:
If anything, your oil consumption should go down when switching to
a synthetic because:
1. They do a better job of sealing, especially in high
temperature areas (rings & etc), this has been proven with
before and after compression tests.
2. When conventional petroleum oils near their limit (~300 - 350
F) they oxidized quite rapidly. When your oil reaches these
temperatures it will start to evaporate and via the PVC
system "burn". Repeated or sustained periods at these
temperatures will result in a "thickening". This action is
quite similar to the manufacturing process that created it
(refinement, a distillation procedure).
Synthetic lubricants can "easily" sustain these temperatures
and surpass then by a 100 F and more. Not only being able to
take the heat better, because of the reduced friction and
thermal conductivity, temperature reductions have been
measured where ever these products have been used.
Note: When switching to a synthetic make sure your engine is
mechanically sound and not all sludged up. Synthetics will clean
things up and loosen up sludge deposits. You're better off by
using a flush procedure(s) first. This is very important, if not
you may be opening a big can of worms (or many cans of oil for
sure).
Vern Metzgerdonch@teklabs.UUCP (09/17/83)
I have a tale regarding a particular brand of synthetic oil that might be of interest. About six years ago, my newly acquired 912 Porsche needed a major engine rebuild. After doing the job, one of my prime concerns was to never have to do the job again; hence, the choice of oil seemed very important. A bit of research on my part and salesmanship of a local synthetic oil distributor convinced me to try ALL PROOF, a brand that the local Formula Ford crowd was using with noticeable success on the racetrack. After breaking in my engine on Kendall 30 wt., I ran ALL PROOF for almost 20,000 miles in the Porsche. What I liked: --cold starting in a car with no chokes was vastly improved, including near zero temperatures; --oil consumption was very low (new, tight engine, most likely) --visible exhaust smoke was almost eliminated (very important since the local motor vehicles department inspected for same among other things); What I hated: (one entry here) --a second expensive engine rebuild at about 20,000 miles as evidenced by non-existent main and big-end rod bearing material, and rust and corrosion on the cylinder walls. The local engine guru who reground the crank (its last grind) and observed the rusty cylinders voiced the opinion that poor lubrication clearly was the problem. When told of the oil, he just shook his head and said he'd seen similar results with other engines using "synthetics". Particularly, he said that rust protection with synthetics was very poor and that exposed internal surfaces such as cylinder walls were prime candidates for rapid rusting if the oil didn't protect properly. One mitigating fact here was the discovery that the oil cooler on that Porsche wasn't changed at the first rebuild, and that it apparently was restricting oil flow to the bearings. So I can't damn that particular oil out of hand. At the same time, I ran the same oil in my motorcycle, an Italian Moto Guzzi. After 10,000 and the Porsche experience, it too went back to Kendall. However, it did suffer a failure directly related to the synthetic. Its cam is chain driven and has a thick rubber chain tensioner. I discovered that the rubber had swollen to almost 50% original size and had become very mushy. This is a common complaint with some synthetics. Indeed, it is sometimes tauted as a virtue in the sense that rubber seals that have hardened and begun leaking can become soft and compliant again. I suggest that this effect can go to an extreme. All in all, I liked the everyday benefits of having a synthetic oil in my vehicles, particularly the cold starting ease. Getting me to trust one again will be an uphill battle. I still have all the Porsche engine parts receipts to document my caution. Don Chitwood Teklabs, Tektronix, Inc. Beaverton, OR
inc@fluke.UUCP (Gary Benson) (09/27/84)
Thoughts on Mobil 1 and other synthetic oils:
-In 1981, a friend of mine purchased a new Honda (I forget the model, but
think it was a super-Civic of some kind). After the break-in, he drained
out the factory oil and replaced it with Mobil 1. He told me that the
engine performed noteicably better in several ways: his subjective
impression was that he could wind the engine tighter without feeling
that it was about to spring, and in highway driving noticed an increase
in mileage of over 10%.
-In 1983, I bought a new Toyota Celica, and asked the Service Manager of
the dealership what he thought of the story about my friend. He said
that it could well be true, but that if I used a synthetic, all bets were
off regarding Toyota's liability in case of *any* engine failure during
the warranty period. In fact, he said that since Toyota recommends only
pertoleum-based lubricants, they made it a practice to check for signs
of the use of synthetics as a normal part of in-warranty engine repair.
-Since the synthetics do have a lower viscosity (I've heard that they are
apporximately like 5-weight), it is nearly impossible to use them in an
older engine, because 5-weight can leak where no 10 can.
The bind, then is this: to really use a synthetic, you've got to have a
tight engine in top condition, which for most of us means NEW. But if you
use it in a new engine, you chance losing any warranty rights you may have,
at least in the case of Toyota.
--
Gary Benson ms232e -*- John Fluke Mfg Co -*- Box C9090 -*- Everett WA 98206 USA
{microsoft,allegra,ssc-vax,sun,sb1}{decvax,ihnp4,tektronix!uw-beaver}!fluke!inc
duetotheshortageofrobotsallourworkersarehumanandmayreactunpredictablywhenabusedhrs@houxb.UUCP (H.SILBIGER) (10/03/84)
Does anyone know whether synthetic oil can be used in a rotary Mazda engine, since it also injects the oil into the combustion chamber to lubricate the seals. It would add to the operating cost, since this takes about 1 qt. per 1000 miles, but it might be worth it if it also reduces wear. Herman Silbiger houxb!hrs
250jmg@sunybcs.UUCP (J Matthew Good) (10/11/84)
> Thoughts on Mobil 1 and other synthetic oils: > > -In 1981, a friend of mine purchased a new Honda (I forget the model, but > think it was a super-Civic of some kind). After the break-in, he drained > out the factory oil and replaced it with Mobil 1. He told me that the > engine performed noteicably better in several ways: his subjective > impression was that he could wind the engine tighter without feeling > that it was about to spring, and in highway driving noticed an increase > in mileage of over 10%. > In 1977, I puchased a new Chevette. I also felt the engine ran better after installing Mobil 1. In fact, on one occasion, as I was passing on a 2 lane highway, the driver of the car I was passing decided to race. And there was a car comming the other way, so in third gear I proceeded to accelerate to almost 75 miles/hr, about 1000 rpm ABOVE redline, yet I never had any engine trouble during the entire subsequent 14000 miles I owned the car. I would still have it, but someone totalled it for me, so. > -In 1983, I bought a new Toyota Celica, and asked the Service Manager of > the dealership what he thought of the story about my friend. He said > that it could well be true, but that if I used a synthetic, all bets were > off regarding Toyota's liability in case of *any* engine failure during > the warranty period. In fact, he said that since Toyota recommends only > pertoleum-based lubricants, they made it a practice to check for signs > of the use of synthetics as a normal part of in-warranty engine repair. > This is a sticky situation. Read the owners manual, VERY CAREFULLY!!!! If the manual says petroleum-based only, then by all means don't use synthetic, as they have covered their *SSES! However, if there is no prohibition in the manual, go right ahead and use it if you want. There is a federal law regarding warrantees which requires all conditions of warrantee to be in writing, and this warrantee to be presented to the consumer BEFORE purchase. Since Mobil 1 meets or exceeds the requirements of API service SE-SF(/CC?) the only limitations are on the actual viscosity of the oil itself. Also, despite the dealers claims, most do NOT have facilities for determining the origin of the base used in the oil. IN OTHER WORDS, the dealer may have been expressing his/her personal bias against Mobil 1. > -Since the synthetics do have a lower viscosity (I've heard that they are > apporximately like 5-weight), it is nearly impossible to use them in an > older engine, because 5-weight can leak where no 10 can. > > The bind, then is this: to really use a synthetic, you've got to have a > tight engine in top condition, which for most of us means NEW. But if you > use it in a new engine, you chance losing any warranty rights you may have, > at least in the case of Toyota. > While it is best to start any engine on Mobil 1 when new, it is possible to switch at any time. Indications that such a switch would not be good are: 1) Blue-gray exhaust at ANY time. Starting, acceleration, deceleration, idling, ANYTIME! 2) Any signs of leakage, such as spots under car after parked for any period of time. 3) Use of more than one-half quart (liter) of oil between oil changes. Oil consumption WILL increase. This is doubly important, as Mobil 1's biggest advantage is its extended service interval. However, never EVER exceed the recommended mileage limit in your owner's manual! With petroleum-based oils, the 6000+ mile recommendations on new cars are far too high for safe maintenance. Remember, these people are in business to sell cars, not oil! 3000 miles is tops without going to a synthetic. 4) Do Not switch in any engine with a TURBO, or in a Diesel. These engines have special service intervals which are to frequent for synthetic to offer any advantage. These guidelines would also apply to the AMSOIL synthetics as well, except I believe AMSOIL offers a selection of viscosities, unlike Mobil 1, which comes in 5W-40 only. J. Matthew Good !sunybcs!250jmg