Reducing wear at startup on a low service engine

[Captain_Klink]

and PAO is very non polar, so the adhesion is less, and protection is less. Group 1,2, and 3 are increasingly polar, which says use group 2 and 3, sooner than 4. Group 5 is highly polar, and must be added to true synthetics, or the oil film strength will break down.
This makes me feel good about using the cheaper group 3, and blending 2 + 3.

 

[Trvlr500]

I've always let my engines warm up before driving away. It seems to me that oil lubricates better at normal operating temperature and putting a load on a cold engine just doesn't make sense. Especially if it is REALLY cold like down around 30 degrees or less. Also, it helps to make sure the ring packs and everything else have a good oil flow.

Duty cycle has everything to do with engines lasting along time just as with anything else such as electronics I would think. The constant heating up and cooling down of a material causes wear and an engine is no different. I just let my car idle if I'm not going to be out of it for very long.

 

[river_rat]

Originally Posted By: Trvlr500
...Especially if it is REALLY cold like down around 30 degrees or less.

Above zero? That ain't cold!

 

[Gary Allan]

Originally Posted By: Trvlr500
I've always let my engines warm up before driving away. It seems to me that oil lubricates better at normal operating temperature and putting a load on a cold engine just doesn't make sense. Especially if it is REALLY cold like down around 30 degrees or less. Also, it helps to make sure the ring packs and everything else have a good oil flow.

Duty cycle has everything to do with engines lasting along time just as with anything else such as electronics I would think. The constant heating up and cooling down of a material causes wear and an engine is no different. I just let my car idle if I'm not going to be out of it for very long.



Get a block warmer on a timer. Oil temp takes a long time to hit any significant temp. Now "fluidity" when transitioning from being still and cold ..that's not such a big deal.

My reasoning says that you pay an extra penalty in the fuel enrichment mapping required to maintain an idle with an engine that probably barely produces enough power to stay running at that speed.

 

[friendly_jacek]

Originally Posted By: BuickGN
Originally Posted By: friendly_jacek
Originally Posted By: ekpolk

And FWIW, the Toyota/Lex hybrids, which in urban driving do far more engine starting and stopping than most cars (mostly hot though) have a specifically programmed-in feature for starting. Motor-Generator-1 (the smaller one that's connected to the center shaft of the PGS) spins the ICE to about 1000 rpms before it orders up fuel and spark. This promotes smooth ICE starts, and ensures that the pump has built oil pressure before the ICE sees real driving loads on critical parts. These cars have neither traditional starters, nor alternators, nor PS pumps. MG1 in effect acts as both a starter motor and an alternator if needed (the inverters normally make plenty of AC drawing from the hefty current and voltage sent from the TB).

Anyway, all this suggests to me that there is legitimate concern about startup wear, even in a warm or hot engine. Why would have Toyota bothered with such systems if not?


You are correct, there is a concern of increased bearing wear in hot (but not cold) engine on restart. It is well explained in this PDF on page 4 under the paragraph Tempereture of the Oil (sorry, could not copy and paste):
http://www.zddplus.com/TechBrief11 - Internal Combustion Engine Lubrication.pdf

So, thicker is sometimes better.

I got the link from this thread:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1531540&fpart=2


I'm surprised no one commented on this. It clearly shows the relationship between viscosity and protection.


I'm actually not surprised there were no comments. You can call me a cynic.

 

[Gary Allan]

It gets a small mention. I tend to view that as a self correcting condition. While the paper cites long times to reach pressure when cold being dealt with by the elevated viscosity of the residual oil film, one should reason that the lower viscosity hot start is refreshed almost instantaneously. Long time to pressure ..turns the ultra high viscosity residual into a low one. Short time to pressure restores the supply before the low viscosity fluid is an ultra low viscosity fluid. YMMV, but I see some sensible balance to the two states.

Side comment: Whomever authored the paper deserves the beverage of his/her choice on me. He/she must have come up from the ranks without a clue. Only someone of that discipline formation from lower to upper strata could possibly communicate that without a bunch of equations with alien symbols and geek speak under the false assumption that only people who already know the process are reading the paper. That is, if you can understand it to begin with, you're actually doing a peer review of the document. Most are written as a testimony to the authors knowledge ..not for his/her communication skills of the content.

 

[Trvlr500]

Originally Posted By: river_rat
Originally Posted By: Trvlr500
...Especially if it is REALLY cold like down around 30 degrees or less.

Above zero? That ain't cold!

I knew someone would say that!

 

[Trvlr500]

Originally Posted By: Gary Allan
Originally Posted By: Trvlr500
I've always let my engines warm up before driving away. It seems to me that oil lubricates better at normal operating temperature and putting a load on a cold engine just doesn't make sense. Especially if it is REALLY cold like down around 30 degrees or less. Also, it helps to make sure the ring packs and everything else have a good oil flow.

Duty cycle has everything to do with engines lasting along time just as with anything else such as electronics I would think. The constant heating up and cooling down of a material causes wear and an engine is no different. I just let my car idle if I'm not going to be out of it for very long.



Get a block warmer on a timer. Oil temp takes a long time to hit any significant temp. Now "fluidity" when transitioning from being still and cold ..that's not such a big deal.

My reasoning says that you pay an extra penalty in the fuel enrichment mapping required to maintain an idle with an engine that probably barely produces enough power to stay running at that speed.


You're probably right but my car was made in 1973 and there is no computer mapping anything on it. The block heater would be a good idea but where I live it rarely gets down below 20 or 30 degrees and I have no where to plug in a block heater.

 

[Gary Allan]

Then carry on. Your 36 yo engine (unless it's been replaced) obviously could care less about your warm up habits

..but it wouldn't matter if it's 70F out. Timed right the whole fuel enrichment process can be bypassed with a block warmer. It's not sensible for the typical life expectancy of a chassis, but you kinda blow that notion out of the water in your case.

Is this some crate engine thing, as in "engine by Jeg's or Summit", the home equity line of credit magnets??

 

[river_rat]

Originally Posted By: Gary Allan
Side comment: Whomever authored the paper deserves the beverage of his/her choice on me. He/she must have come up from the ranks without a clue. Only someone of that discipline formation from lower to upper strata could possibly communicate that without a bunch of equations with alien symbols and geek speak under the false assumption that only people who already know the process are reading the paper.

And you, sir, deserve a beverage of choice for writing this very truthful and egalitarian observation.

 

[zoomie]

seeing as Im half-cut again, I've got a choice in my igloo of molson's or alberta genuine draft...for starting this thread!

...jokes

but really, I gotta share, I saw an airshow today and there was a Avro Lancaster doing flyby's... a four RR V-12 Merlin engine heavy.

It purr's and growl's at the same time

 

[zoomie]

 

[zoomie]

oh well

http://www.youtube.com/watch?v=_sarYH0z948