Whenever I start a vehicle, even a warm one, it is the first thing I do after getting in the car. I then fasten the seat belt, check the mirrors, etc. I figure those few seconds are important to the oil.
How many miles is a cold start equal too?
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I read Sikorski's 30 year old book and frankly I think he was a bit of a kook. One part I remember was him splitting hairs over dropping your interval from 3000 miles to the upper 2000's based on certain conditions. His big concern was the oil "dumping" contaminates if I remember.
That said, what about anti-wear additives? Don't they provide barrier protection until the film protection develops? I think the cold start is not the huge deal people make it out to be unless you start flooring it while the engine is cold...
That said, what about anti-wear additives? Don't they provide barrier protection until the film protection develops? I think the cold start is not the huge deal people make it out to be unless you start flooring it while the engine is cold...
olddognewtrks & DavoNF, how 'bout this:
Inverted bottle, inlet in bottom, oil goes in under pressure, pressurizing air cushon above. There's a 'Y' at the bottom so there's two hoses. One has a one way valve (in ONLY), the other has a solenoid that allows flow in any direction. Solenoid is normally closed, so oil pressure in bottle is MAX oil pressure achieved by your car during that cycle. Shut your car down, pressure stays 'cuz it can't get out the one way valve (wrong direction) or the solenoid (closed). Then, when you want to start your car, you open the solenoid first, start it, then close the solenoid again when oil press. light goes out.
Can you tell what I think about when I can't sleep at night
Dave
Inverted bottle, inlet in bottom, oil goes in under pressure, pressurizing air cushon above. There's a 'Y' at the bottom so there's two hoses. One has a one way valve (in ONLY), the other has a solenoid that allows flow in any direction. Solenoid is normally closed, so oil pressure in bottle is MAX oil pressure achieved by your car during that cycle. Shut your car down, pressure stays 'cuz it can't get out the one way valve (wrong direction) or the solenoid (closed). Then, when you want to start your car, you open the solenoid first, start it, then close the solenoid again when oil press. light goes out.
Can you tell what I think about when I can't sleep at night
Dave
This is taken from Elf's web site:
A good quality oil provides motorists with a number of benefits :
-easier cold start and reduced wear (20 to 30% of engine wear occurs between startup and the time the engine reaches optimal temperature),
-longer engine life,
-fuel savings as a result of reduced friction of moving parts and better engine performance.
I do agree that letting your car idle for 20-30 sec every time you start is the best way to make your engine last waaaay longer.
[ February 13, 2004, 11:32 AM: Message edited by: yannis ]
A good quality oil provides motorists with a number of benefits :
-easier cold start and reduced wear (20 to 30% of engine wear occurs between startup and the time the engine reaches optimal temperature),
-longer engine life,
-fuel savings as a result of reduced friction of moving parts and better engine performance.
I do agree that letting your car idle for 20-30 sec every time you start is the best way to make your engine last waaaay longer.
[ February 13, 2004, 11:32 AM: Message edited by: yannis ]
I've heard so many different figures (50 miles, 200 miles, 500 miles etc etc) over the years I won't even guess.
I do know the small town near where I live you see a lot of little old grannies in cars that are 10-20 years old.
These cars are driven from their garage to the grocery store and back. The car has probably never been at highway speeds in its life.
Some of these cars only have 5,000 - 20,000 km on the odo. Yet they all seem to puff a heavy blue cloud behind, and local mechanics have reported the oil change every 6 months comes out chunky.
Much like PU/D vehicles, they may not have many miles but the motors are shot. I would never buy a used FedEx or UPS truck, that's for sure: stop, shut off, drop package, start up, race down street, shut off, drop package, repeat 100x per day.
You have to use common sense here. It should stand to reason that a cold start puts a LOT of wear on a motor compared to constant highway driving, as the parts are starting dry.
That's why it's so important to use the correct oil in winter, preferably a 0W-30 synthetic with MRV of less than 20,000 cP at -40 C. The faster you build oil pressure and lubricate to the top end, the better.
There are all sorts of gadgets out there that store pressurized oil in a container, so you use a manual valve to pressurize the galleries before starting. An old favorite is the Pre Luber system.
Jerry
I do know the small town near where I live you see a lot of little old grannies in cars that are 10-20 years old.
These cars are driven from their garage to the grocery store and back. The car has probably never been at highway speeds in its life.
Some of these cars only have 5,000 - 20,000 km on the odo. Yet they all seem to puff a heavy blue cloud behind, and local mechanics have reported the oil change every 6 months comes out chunky.
Much like PU/D vehicles, they may not have many miles but the motors are shot. I would never buy a used FedEx or UPS truck, that's for sure: stop, shut off, drop package, start up, race down street, shut off, drop package, repeat 100x per day.
You have to use common sense here. It should stand to reason that a cold start puts a LOT of wear on a motor compared to constant highway driving, as the parts are starting dry.
That's why it's so important to use the correct oil in winter, preferably a 0W-30 synthetic with MRV of less than 20,000 cP at -40 C. The faster you build oil pressure and lubricate to the top end, the better.
There are all sorts of gadgets out there that store pressurized oil in a container, so you use a manual valve to pressurize the galleries before starting. An old favorite is the Pre Luber system.
Jerry
What about the aunt millie test? Didn't it show that there was no wear difference between driving 1 mi. and then shutting the engine off and repeat for several years?
Maybe we're confusing things here...does the engine get beat-up with frequent cold starts or the oil?
Aside from needing to change the oil a little more frequently due to extreme cold, fuel dilution, etc., and assuming this is done, I think the extra wear is nowhere near the 500 mark...ie. it's possible to have a 400-500k mi. cars in Canada as in California...(few and far in between though...the winter kills everything else)
Maybe we're confusing things here...does the engine get beat-up with frequent cold starts or the oil?
Aside from needing to change the oil a little more frequently due to extreme cold, fuel dilution, etc., and assuming this is done, I think the extra wear is nowhere near the 500 mark...ie. it's possible to have a 400-500k mi. cars in Canada as in California...(few and far in between though...the winter kills everything else)
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I'm going to say it again: I'm sure those high wear miles at cold start can happen only at very low temperatures.
By the way, are Audis the only cars that have oil retention valves in the heads?
I know for a fact of another Audi driver, who had let his Audi sit for half a year (over the winter, to make things worse) without starting it up. He was so worried about lack of lubrication that he removed the valve covers to see if the oil would flow (and splash, I bet!). He said oil appeared within a couple seconds of starting the engine.
Also, don't forget how sticky oil is!
By the way, are Audis the only cars that have oil retention valves in the heads?
Also, don't forget how sticky oil is!
"The startup period is the time when the engine experiences the most wear." (For what that's worth...)
http://www.shell.ca/code/motoring/tips/engines.html
My mind went to the pre-oiler as well. The definitive way to answer this question is to take two identical new vehicles, fit one with a pre-oiler, and drive the engines to failure (100K, 200K, 300K miles, whatever), and then compare the two. Obviously this wouldn't be a statistically valid sampling, but you get the idea...
http://www.shell.ca/code/motoring/tips/engines.html
My mind went to the pre-oiler as well. The definitive way to answer this question is to take two identical new vehicles, fit one with a pre-oiler, and drive the engines to failure (100K, 200K, 300K miles, whatever), and then compare the two. Obviously this wouldn't be a statistically valid sampling, but you get the idea...
A difficult thing to quantify ....
I'd say a "cold soak" start in subfreezing temps is worth at least several hundred miles in terms of main/rod/cam bearing wear. These parts run with hydrodynamic lubrication and almost no wear occurs after full oil pressure is achieved.
By contrast most of your cam/lifter and piston/ring/cylinder wear occurs in normal use. There is a chemically bonded coating of AW additives from when the engine was last used and this prevents excessive wear until oil circulation is achieved ....
Finally, any time you load or unload the engine, the wear rate increases. Driving at constant speed and constant load, minimizes wear in all types of engines.
I'd say a "cold soak" start in subfreezing temps is worth at least several hundred miles in terms of main/rod/cam bearing wear. These parts run with hydrodynamic lubrication and almost no wear occurs after full oil pressure is achieved.
By contrast most of your cam/lifter and piston/ring/cylinder wear occurs in normal use. There is a chemically bonded coating of AW additives from when the engine was last used and this prevents excessive wear until oil circulation is achieved ....
Finally, any time you load or unload the engine, the wear rate increases. Driving at constant speed and constant load, minimizes wear in all types of engines.
And how man COLD starts is that? With 50 starts a day I would highly doubt any after the first one are COLD. There is a big difference between a start and a cold start.
My old Jeep was kind of like that. Early computer, required the engine to crank for about 10 seconds before the engine will start. My new jeep has the same exact engine, newer computer. Starts on the first or second revolution. I've never thought about it before, but the older engines do seem to last longer even though they are exactly the same...quote:
Originally posted by DavoNF:
We need a little electronic gizmo that would prevent the car from starting on the first key-turn. So you you crank it up, get the oil pressure up, release the key to start on the next turn. Any venture capitalists out there?
Jay, You are one of the few I know that are familar with Robert Sikorsky. His book titled "Drive it Forever" was top notch!
I agree JB. At the time there was practically nothing for the layman that explained how, where, and why engine wear occurred. Sikorsky layed it all out for us in simple terms. Much of his book is outdated now, but it was a great book at the time.
Zmoz, you could get that 'feature' back if you wanted. Put a 'not' gate between your oil idiot light and your injectors. Meaning, you crank and
If idiot light = true then
injector = false
else idiot light = false
injectors = true
endif
Parts would be under $10 for a suitible transistor (or relay) and the 'not' gate.
Dave
If idiot light = true then
injector = false
else idiot light = false
injectors = true
endif
Parts would be under $10 for a suitible transistor (or relay) and the 'not' gate.
Dave
Kestas
Staff member
It depends on the parts you're evaluating, e.g., an oil property, bearings, or cylinder walls.
Yes it is an interesting book with a lot of good advice, but I have no desire to drive like Sikorsky. I like to have fun when I drive. The one thing that stands out about Sikorsky's book (read it about 7 years ago) was that he advocated parallel parking on the street instead of going into a parking lot because going into the parking lot involved several more steering maneuvers and thus helped wear out the steering linkage sooner. I have no desire to "drive it forever" because here in Detroit the road salt destroys the body long before the engine even begins to weaken. The book really does have a lot of good info in it though and is worth a read.
[ February 14, 2004, 01:46 AM: Message edited by: TallPaul ]
to n8vmi, ZmOz, and DaveNF: regarding cranking to pump up oil before starting. My Mazda Protege, and numerous other Japanese cars kill the injectors if the pedal is floored and held before you start cranking. Lift after cranking a bit, the injectors are enabled, and you start. See if your vehicle has the same programming. Only problem, it's gotta be rough on the starter.
I've looked at the pressurized inverted oil reservoirs, and was looking for a system that's not time or reserve volume limited, i.e., an electric pump. My objection to the pressure tank reservoir is the extra quart of oil in the sump that may foam or stress oil seals until you get fully warm. Only then can you rev the engine to pump the extra quart back up into the tank
I've looked at the pressurized inverted oil reservoirs, and was looking for a system that's not time or reserve volume limited, i.e., an electric pump. My objection to the pressure tank reservoir is the extra quart of oil in the sump that may foam or stress oil seals until you get fully warm. Only then can you rev the engine to pump the extra quart back up into the tank
Patman
Staff member
I read that book when I was 16 years old (I'm 34 now) and still use many of his tips!
As pointed out previously, steady state light part throttle driving gives exremely low wear. The BMW million mile Mobil One test is example; some of the oil lubricated parts met factory specs for new after a million miles. Under optimum conditions engines have an extremely long life expectency.
Good thing is most engines can stand numerous cold starts and still go 200-300,000 miles. The worst case scenario would be someone living in a very cold climate and running a mile or so per cold start. I think it was pointed out earlier, 20 year old cars with 60,000 miles; smoking.
I would add, in addtion to the lack of immediate oil pressure is the issue of cold start enrichment. Modern fuel injection is very precise but still has to enrich cold mixtures to compensate for fuel condensation. There is still potential for bore wash on very cold starts, with loss of upper cylinder lubrication. This issue is far less problematic today compared to the auto choke engines of the past.
Good thing is most engines can stand numerous cold starts and still go 200-300,000 miles. The worst case scenario would be someone living in a very cold climate and running a mile or so per cold start. I think it was pointed out earlier, 20 year old cars with 60,000 miles; smoking.
I would add, in addtion to the lack of immediate oil pressure is the issue of cold start enrichment. Modern fuel injection is very precise but still has to enrich cold mixtures to compensate for fuel condensation. There is still potential for bore wash on very cold starts, with loss of upper cylinder lubrication. This issue is far less problematic today compared to the auto choke engines of the past.
In my view, this whole concept is the reason that the taxi cabs in the infamous Consumer Reports oil test showed no difference between synthetic and petro oils.
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