Engine Start-Up Wear

[HBCALI]

Ok, so on the front page article of BITGO (oil 101), it states that "...90% of engine wear occures at initial start-up..." Fine, I can agree with that. But along with that, the author dosn't really tell us how to get around start-up wear. It seems it can only be mitigated, but never avoided.

The article also seems to convey that no matter the scenerio, oil will be too "thick" at start-up to truely protect the engine. So is start-up wear just something we have to live with untill technology increases? What's the scoop? Can it be avoided somehow? Untill I read the ariticle, I thought synthetics addressed that issue. Seems that syns are only good for extended OCI's? Huge topic but worth a quick debate...

 

[AuthorEditor]

A lot of industrial engines and some trucks use a pre-luber that circulates oil before the engine starts up so there is no lag time in building pressure. It's also an argument for using thinner oils, especially when cold, than in the past. Now that we have things like 0W oils I imagine in a few years that will be the standard.

 

[addyguy]

A pre-luber/warmer will pump oil throught the engine and almost completly eliminate start-up wear.

Most won't want to go through the hassle of doing that....!

 

[Chris142]

I think that you could somehow pressurize the oil system before starting the engine. This would stop most if not all of the start up wear.

 

[HBCALI]

Originally Posted By: AuthorEditor
Now that we have things like 0W oils I imagine in a few years that will be the standard.


So switching from 5W-20 in my 2001 Accord to 0W-20 could help avoid start-up wear? I'm already using a synthetic, but how much better would a 0W be? OEM calls for 5W.

 

[edhackett]

That should really read: 90% of engine wear occurs during the first 20 minutes after a cold start.

Oil flow is a minor contributor to start-up wear.

Ed

 

[NateDN10]

Originally Posted By: edhackett
That should really read: 90% of engine wear occurs during the first 20 minutes after a cold start.

Oil flow is a minor contributor to start-up wear.

Ed

So if it's not that oil flow is less right after start up, then what causes wear?

 

[d00df00d]

Originally Posted By: HBCALI
Ok, so on the front page article of BITGO (oil 101), it states that "...90% of engine wear occures at initial start-up..." Fine, I can agree with that. But along with that, the author dosn't really tell us how to get around start-up wear. It seems it can only be mitigated, but never avoided.

Correct. Same goes for all wear. It's impossible to prevent entirely. What you can do is reduce it far enough that it makes no difference for the service life of the vehicle.


Originally Posted By: HBCALI
The article also seems to convey that no matter the scenerio, oil will be too "thick" at start-up to truely protect the engine. So is start-up wear just something we have to live with untill technology increases? What's the scoop? Can it be avoided somehow? Untill I read the ariticle, I thought synthetics addressed that issue. Seems that syns are only good for extended OCI's? Huge topic but worth a quick debate...

The point of that statement is just to say that any improvement in start-up viscosity is a good thing, and there's really no limit on how good it can get.

Synthetics usually do address that issue by pumping and flowing better at lower temperatures.

 

[d00df00d]

Originally Posted By: addyguy
A pre-luber/warmer will pump oil throught the engine and almost completly eliminate start-up wear.

Most won't want to go through the hassle of doing that....!

Good call.

 

[demarpaint]

While a pre-luber is a big help, [I have one on my E-150}. It won't eliminate all start up wear, especially during colder seasons. In order for oil to fully protect, the engine and oil have to at optimal operating temps, which can take up to 20 minutes or longer to reach. So the startup wear is occurring until the engine oil reaches optimal temps, usually 20+ minutes. Preheating the oil and a pre-luber would be your best shot at reducing start up wear, and wear while the engine is getting to optimal operating temps. JMO

 

[flatlandtacoma]

Originally Posted By: HBCALI
So switching from 5W-20 in my 2001 Accord to 0W-20 could help avoid start-up wear?
It depends. If you are routinely starting your engine at 40 below zero with no block or pan heater, then yes. Otherwise, probably not.

 

[chubbs1]

Originally Posted By: demarpaint
While a pre-luber is a big help, [I have one on my E-150}. It won't eliminate all start up wear, especially during colder seasons. In order for oil to fully protect, the engine and oil have to at optimal operating temps, which can take up to 20 minutes or longer to reach. So the startup wear is occurring until the engine oil reaches optimal temps, usually 20+ minutes. Preheating the oil and a pre-luber would be your best shot at reducing start up wear, and wear while the engine is getting to optimal operating temps. JMO


Well said. Start up wear is unavoidable still and all most of us can do is use a 0w and hope our ADBV works on our oil filter. Especially in cold temps but also warm ones too.(0w & 5w)

 

[greenjp]

FWIW I've had several of my UOAs done after intervals over the winter, and there is no apparent difference (wear metals or other indicators) from those done in the warmer months. I use 5W synthetics FWIW, my commute is 19 miles and ~30 minutes.

I'm not sure modern lubes at "normal" cold temperatures present anything worth worrying about wrt "start up wear".

jeff

 

[edhackett]

Quote:
So if it's not that oil flow is less right after start up, then what causes wear?


The largest contributor to wear when cold is the fact that the operating clearances are not to specification. Different metals expand at different rates. Until the engine is fully heat stabilized the clearances are off. The most striking example is pistons being oval. They are machined out of round so that as the various thicknesses of metal heat up the piston achieves a round shape. A cold piston can have clearances that are four to five times normal operating clearance on one axis.

Some anti-wear additives are not effective until the oil warms up.

Rich mixtures wash oil from cylinder walls. This is less of an issue with fuel injection, but is returning as a real problem with direct injected engines.

Ed

 

[JOD]

Originally Posted By: flatlandtacoma
Originally Posted By: HBCALI
So switching from 5W-20 in my 2001 Accord to 0W-20 could help avoid start-up wear?
It depends. If you are routinely starting your engine at 40 below zero with no block or pan heater, then yes. Otherwise, probably not.

I'm not sure I agree with this. If you're comparing oils among a product grouping, the 0W oil will generally be thinner/flow better at any ambient temperature, not just 40 below?? And at least as far as I was able to tell, it appears that a 0W oil gets up to operating temperature more quickly. Both of those factors seem like they'll reduce wear, regardless of ambient temperatures.

 

[Errtt]

We used pre-heat systems (coolant & oil) in large diesel stationary applications. We could manually run the pre-lube then start the engine.
The heated coolant system had full time circulating pumps when the engine wasn't running.
The heated pre-lube system was normally ran (timers) automatically at set points while an engine wasn't running. The manual override was for when readying a start.

The thing about these engines in power plant applications is they turn over via air, then the fuel goes 100% til rated speed is achieved. The chugging up to speed duration puts the journals to work while at the same time the engine driven oil pump is ramping up to speed building up oil pressure.

 

[Loobed]

Originally Posted By: HBCALI


So switching from 5W-20 in my 2001 Accord to 0W-20 could help avoid start-up wear?


slightly reduce

 

[Steve S]

First Startup wear can be caused by oil too thick at startup... Now the cause from too thick oil is not the explaintion in oil 101, mostly is it caused by for example us1ng a straight 30 wt oil on freezing temps. For an example suck up a thick milkshake through a straw, it takes a long time for the thick milkshake to reach your mouth if at all . The exact same happens with the wrong oil viscostiy used at startup temps. The 0w and 5w and 10w oils usually eliminate this and high quality syn oil has an even lower temp advantage. Now lets get into the real nitty gritty that little if anything can be done about start up wear. When the engine is cold the pistons are oval[measure one]. The clearances are looser so the pistons rock more in their bores. the more space between the parts the more wear. Then to run when the engine is cold the feul mixture is richer, carb. as well as feul injection. The richer mixture is needed and washes oil from the cyl walls more. The same happens throughout the engine. When at operating temps in simple terms the engine clearances are at their best and remember everything is a compromise. Then some of the additives are temperature activated so warm oil works better. The air feul mixture are leaner etc. The longest lasting engines are the ones run the longest at operating temps.

 

[Steve S]

Originally Posted By: Loobed
Originally Posted By: HBCALI


So switching from 5W-20 in my 2001 Accord to 0W-20 could help avoid start-up wear?


slightly reduce


Maybe at minus 49*f there is not enough difference at most temps to notice a difference considering that there is residual oil film on the motor parts to provide lube for the micro second if there is that much time between the 0w and 5w-20 oils.

 

[AuthorEditor]

Here in the Northeast the good news is that start up wear won't ruin the engine before the car rusts out!