Tow Beast - synthetic vs conventional motor oil

[seahouse]

Hey Catigale--

There is no load on the engine when starting

What
It seems to me that a violent explosion happens when the spark plug first fires, driving the piston downward and tremendous pressures (hundreds of psi) are placed on the main (and other) bearings. This happens at the very instant the motor starts. You lost me when some how there is no load on the engine then????

A dry bearing then = contact= wear. The Romans knew this over 2000 years ago on their chariots.

Not to mention that the engine runs rich at startup and raw fuel is condensing on the cold cylinder walls and washing away any oil that was remaining from the last shutdown.

And not to mention that any modern engine will for a short period engage a fast idle, farther increasing engine load.

All this before you have even had a chance to touch the throttle or put it in gear.

Any engineer (PEng of course) you will consult with will confirm that there is no physical contact between a properly designed and constructed (most are in a modern engine, which is why they are so reliable) shaft and bearing due to the hydrodynamic wedge effect. Hence I opened with the term "esoteric" nature of the topic.

OK, OK. The US/ Canadian law thing; I confess you have to live closer to the border to know what that one's about. In some areas (particularly in matters automotive) we have a "rubber stamp" in Canada. It facilitates trade. Trade of goods and knowledge is good.

Cheers - Brian.

[Scott]

Le Beast? Mon dieu'

C'est la vie

[Catigale]

When the engine is started, there is minimal load on the crankshaft until the transmission is engaged - the 'load' needed to turn the crankshaft and other engine parts is minimal compared to the load of the car and contents.

The bearings and piston walls are not dry on startup. I worked on a project laser cracking bearings and cylinders of engines a few years ago - as part of that work the client studied the residuals - and there is a sizeable amount of oil that resides on these parts after shut-down, in a well-designed engine.

The 'excess gas' washing the walls probably was applicable to Grandpas Ford Torino GT with the Rochester Quadra Jet with four chokes, but a modern FIJ engine is much more controlled and metered on startup

SAE trumpets the "90% engine wear on startup" story but I have never had anyone able to produce a good study on this when challenged. They also made a statement about 10 years ago that "every startup is like a 500 mile trip"

If you do the math on that one, it doesn't hold water (or oil) either.

I do think it makes sense to start any engine, and give it 15 seconds to run before you load it up as opposed to flooring it out of the driveway, but I cant point to a scientific basis on this.

I export to Canada. It is not a rubber stamp in my business at all.

[TAW02]

I May be old, ugly fat and lazy but, I have to lay claim to the original tow beast. My kids named the old ford that years ago. They even went as far as putting "Beast" on the step bumper.

Beautiful machine Mr. Scott!
I have a 1976 F150 (pretty rusty) that has an engine swap done on her way back when she was young. Has a 353 Detroit Diesel ... a real tow beast in her time. Still runs but am looking to sell 'er.

I listen to the Magic Mechanic every saturday and have heard him extoll his knowledge of synthetic oils. The one thing that impresses me about 'true' synthetic oil is, that this oil flows toward heat. Petroleum oils flows away from heat. For synthetic, this means it tends to do a superior job at getting into rod and main bearing et cetra.

Larry Perry hosts the Magic Mechanic every saturday and has been doing it for over 25 years. He owns his own shop and is very well respected for his knowledge and his honesty in his business ethics. He has a live radio feed on his Magic Mechanic web site and welcomes callers, answering all types of questions relating to car problems and other equipment types as well. I must confess, I often listen for the entertainment of it all. But have yet not learned at least something during each show.

For instance, a lady calls in and tells Larry she has an 03 Cavalier. Runs great everything works ... well not exactly all the time. Claims her air conditioner will only run (or keep cool) when she driving above 20MPH. Whenever she comes to a stoplight, the AC turns into HEAT! Well, needless to say, she is frustrated at this and the Dealership she has gone to to get it fixed. She goes on to say that the dealership repair shop tells her it is a defective AC compressor and to fix it it will cost around two thousand dollars!

Larry laughs, gives a bit of praise to her for being smart enough to NOT walk away from this dealership, but to RUN away! He then describes what is causing the problem, tells her that she can fix it herself, tells her how and where to buy the part. And all for less than 20 dollars!

Like I said. I learn something from his show every saturday

[Catigale]

The one thing that impresses me about 'true' synthetic oil is, that this oil flows toward heat. Petroleum oils flows away from heat.

Ive never heard this. Not sure what it means.

[grady]

The one thing that impresses me about 'true' synthetic oil is, that this oil flows toward heat. Petroleum oils flows away from heat.

Ive never heard this. Not sure what it means.

It does not make sense? What fluid dynamic property are they trying to explain with that statement.

Hey I bet those Mac 36 guys could answer all of this.

[TAW02]

The one thing that impresses me about 'true' synthetic oil is, that this oil flows toward heat. Petroleum oils flows away from heat.

Ive never heard this. Not sure what it means.

As true with silicone electronics a silicon diode for instance over that of a copper based conductor. As heat rises so does resistance in carbon based materials such as metal like copper and silver. On the other hand as heat rises, silicon resistances are reduced and tend to flow toward heat.

A true synthetic oil (like Amsoil) is silicon based and behaves as such.

These same molecular traits are inherant in true synthetic oil. Pretty ideal for lubricants, but that only scratches the surface. There is more ....

[kmclemore]

...but that only scratches the surface.

...not if it's lubricated properly!

[seahouse]

Hi Catigale!

To see what happens, it helps to consider the extreme situation. The amount of oil remaining in bearings and on the cylinder walls declines with time. Let an engine sit and the longer it sits the less oil is available for lubrication on startup.

I know of cases (old boats in particular, but any engine in general) where and engine has been sitting for (2+) years. A guy goes to start it up, and it gauls up and seizes, sometimes within seconds. The common conclusion is that the engine was seized up from sitting. The reality is that the engine was not seized up at all until it was improperly started up dry. Good startup protocol in such a circumstance would call for manually lubricting the engine before attempting to start it, such as oil in the spark plug holes and spinning the oil pump with a drill etc.

The fact that fleet vehicles (taxis/ couriers), with far fewer start/stop cycles than normal, last much longer and wear at reduced rates than others is evidence enough that startup/warmup, shutdown/cooldown cycles accelerate engine wear.

Even a modern, computer-controlled engine enrichens the fuel/air ratio on startup, and even without this enrichening the cylinder walls are cold in a hot combustion environment and the fuel condenses on them, much like moisture on a cold beer does in your hands on a hot day, even if the humidity is not excessively high.

I export product to the States and Europe, and import from the States, and there ain't no rubber stampin' going on there fer sure! "Fortress North America" was a great plan, but a lot of people make a lot of money with the status quo.

There has been an active ongoing effort to harmonize trade regulations between the two countries, with some success, particularly in commercial goods. I can self-broker goods of just about any value into Canada, but the US Brokerage lobby is big, and there is a $2000 limit on goods going into the states for that! But the paperwork load is still high.

But I digress. The auto pact has harmonized a lot of engineering standards between the two countries and Mexico, and very shortly the auto safety regulations for Canada and US will be fully synchronized and identical. Some things are "rubber stamped" both ways. I'm not a lawyer of course, but I wouldn't be surprised to hear of cross-border jurisprudence going on... "but your honour, this is the way they do it in the US".

Best regards- Brian.

[Catigale]

The fact that fleet vehicles (taxis/ couriers), with far fewer start/stop cycles than normal, last much longer and wear at reduced rates than others is evidence enough that startup/warmup, shutdown/cooldown cycles accelerate engine wear.

Never heard this. I agree that fleet vehicles accumulate more miles than private vehicles, but that doesnt mean they last longer. For years, the advice was against buying fleet vehicles of any kind.

I honestly think this cold start story was passed down by great grandpa down to us with no basis in fact.

To close the original thread topic - I decided to stick with Castrol 10W-40 for Le Teiu- Beastie after reading the sage advice.

[Blackjackr]

As a phone tech in Arizona i am glad they don,t have hr clock's on the motor in my fleet vehicle, since during the summer it started once in the morning and shut off after my 10 hr shift. Sure 100k miles on it but would be 300k if the idle time was driving. In case your wondering we have laptops mounted in our van and when its 115 outside we want to keep the ac on the laptop going. During the winter its not a issue.