Taking It Easy on a Cold Engine - Why?

[Shannow]

Originally Posted By: StevieC
Here... 5:30 in

https://www.youtube.com/watch?v=tYkg0oDUXs8


Originally Posted By: Shannow

It's a sideshow stunt.


why would they compare a conventional 15W40 with a synthetic 5W40 at -37C ?

No 15W oil has any place at -37C...it's MRV is only tested at -25C.

And besides, these stunts are "pour point", which was invalidated as applying to cold starting back in the '80s, being replaced with MRV, and specific cooling regimes.

So YES, if you are trying to work out which oil will flow through the filler if you are changing the oil at -37C, choose the 5W40...

but these stunts don't tell you squat about lubrication.

 

[StevieC]

I give up. Congratulations on the BITOG impossible award of excellence.

 

[Shannow]

Originally Posted By: StevieC
I give up. Congratulations on the BITOG impossible award of excellence.

OK, tell me what I'm missing by comparing two different grades, and declaring the 15W dino deficient ???

You DO understand how oil is delivered within an engine don't you ?

You DO understand that cold starts aren't "dry" don't you ?

edit...here's another one that's usually trotted out at this juncture...

 

[ARB1977]

I'm a conservative driver more so at the first start up.

 

[ARB1977]

Originally Posted By: Shannow
Originally Posted By: StevieC
I give up. Congratulations on the BITOG impossible award of excellence.

OK, tell me what I'm missing by comparing two different grades, and declaring the 15W dino deficient ???

You DO understand how oil is delivered within an engine don't you ?

You DO understand that cold starts aren't "dry" don't you ?

edit...here's another one that's usually trotted out at this juncture...


Interesting

 

[Shannow]

Yep, shows clearly that at the limits of pumpability, you need the right grade for the right temperature.

Doesn't translate as others usually state to 0W flowing more at every temperature.

 

[CR94]

Here's a quirk of the software controlling a Prius that seems relevant to this issue. In the first one minute (approximately, depending on ambient temperature) after a cold start, the system relies much more heavily on the battery for moderate acceleration than it does at other times. During that period, the engine continues its fixed-speed, no-load warm-up routine, while the battery shoulders nearly all the load. Supposedly that behavior is to spare the engine from having to work hard while cold. When that phase ends, the battery discharge current abruptly drops and the engine goes to work normally.

If you press the accelerator hard during this peculiar warm-up stage, the software takes power from the engine as if it were warm--apparently on the theory that briefly abusing the engine by working it cold is not as bad as getting rear-ended.

Posts in past threads of BITOG have stated that Honda blames coked oil rings on customers pushing cold engines too hard. Further explanation of that claim would be interesting.

 

[North to Alaska]

Originally Posted By: Tman220
Originally Posted By: Iowegian
How long does it take for your engine to warm up?
Just curious.


Funny how the service rep told me there was no problem since there was no cel. I asked him then why he was rebuilding my engine since there was no cel for that either...


I suppose that was the 2.4 liter that was rebuilt due to oil consumption? This was a known and very common issue with the 2.4. This was due to a coating on the top ring wearing off because it wasn't robust enough. Low water temp could have prolonged warmup time, which could have aggravated it, but it certainly wasn't the root cause...


You are correct sir.
2010 - 2012 Equinox and Terrain 2.4l had many issue but especially the bad rings. GM did take responsibility for this without having to get sued.

 

[Silk]

Love my 2 stroke scooter - start, down the drive, hit the street and it's WOT and 6,000rpm. It gets enough lube from the oily rag.

 

[Olas]

With a carburettor and manual choke I have no choice but to drive using sense and moderation, until the coolant is at normal op. temp. (my inlet mani and carb base are coolant heated).
This is more for drivability concerns than wear concerns but I feel that addressing one addresses the other equally so it's win/win!

 

[Virtus_Probi]

Thanks so much to all of you for your thoughts, I'm glad this became a lively thread.
At the heart of it, my car "feels" to me like it doesn't really want me to get on it full bore when it's not warmed up, so I will only push it a little bit at such times barring an emergency. I would guess that some of the feeling is from the engine and some from the CVT (who knows what is going on in that thing).

Hmm...take it easy until she's warmed up...sounds like good advice in general.
;^)

 

[barryh]

Here's a reason for keeping the revs down with cold oil at -5 Deg C. This is the core of a cartridge type filter that collapsed under excessive oil pressure.

Filters don't normally collapse but oil will always be bypassing the filter after a cold start.

 

[PimTac]

Originally Posted By: CR94
Here's a quirk of the software controlling a Prius that seems relevant to this issue. In the first one minute (approximately, depending on ambient temperature) after a cold start, the system relies much more heavily on the battery for moderate acceleration than it does at other times. During that period, the engine continues its fixed-speed, no-load warm-up routine, while the battery shoulders nearly all the load. Supposedly that behavior is to spare the engine from having to work hard while cold. When that phase ends, the battery discharge current abruptly drops and the engine goes to work normally.

If you press the accelerator hard during this peculiar warm-up stage, the software takes power from the engine as if it were warm--apparently on the theory that briefly abusing the engine by working it cold is not as bad as getting rear-ended.

Posts in past threads of BITOG have stated that Honda blames coked oil rings on customers pushing cold engines too hard. Further explanation of that claim would be interesting.





Some years years I rented a Nissan Altima hybrid. The morning temps were in the mid-20s. This car started out on battery but after a couple of blocks the engine kicked in. That has to be hard on the motor especially when it’s under load going 30mph.

 

[CR94]

Originally Posted By: PimTac
... Some years years I rented a Nissan Altima hybrid. The morning temps were in the mid-20s. This car started out on battery but after a couple of blocks the engine kicked in. That has to be hard on the motor especially when it’s under load going 30mph.
Was the engine idling (like the Prius behavior I described) to warm itself up during those "couple of blocks"?

 

[Merkava_4]

I feel guilty has heck if I don't let the engine fully warm up before pulling out.

It would be the same for me if I had to go straight from bed to work without having my morning coffee break first.

 

[Olas]

Originally Posted By: Merkava_4
I feel guilty has heck if I don't let the engine fully warm up before pulling out.

It would be the same for me if I had to go straight from bed to work without having my morning coffee break first.


How long dos it take for oil & coolant to reach full temp at idle with no load? Must cost you a lot of money in wasted fuel..

 

[Silverado12]

FWIW I start the car, idle for about 1 minute (until the engine starts to idle down) and drive the 1 mile stretch of subdivision to the main road. Then I drive normally. Never had any engines go bad doing it this way. It looks like from all the videos and discussion that correct grade of oil is most important if you're facing extreme temps.

 

[Smokescreen]

Mine is somewhat similar to Silverado12 except at -20C and colder the block heater gets power 3 hours before start up. I have a mile or so of winding through town before I reach the major double divided highway. Upon embarking I accelerate at a moderate pace up to 55mph cruising speed & during the gear changes the engine doesn't see anything more than 2500rpm. 32 mins later, the engine has been running at 2250RPM steady mins and everything has been well warmed up for some time.

All my vehicles see a very easy duty cycle and run synthetic SOPUS oil.

 

[HemiHawk]

My old Civic Si had a feature to block the engine going past 6k rpm (about when any actual power occurred) while it was cold. I don't know the exact parameters it looked for. I hit that cold limiter once or twice. The issue was that even babying it for a bit in below freezing temps, you'd need some power to get anywhere and to do that with that engine meant some revs.

I believe the BMW M3 has a redline that goes up as the engine warms up as well. All this is to say, engineers must think it best not to run an engine too hard when cold. Maybe its especially true for high reving and/or performance engines.

 

[Garak]

Originally Posted By: Merkava_4
I feel guilty has heck if I don't let the engine fully warm up before pulling out.

In some vehicles, that wouldn't even be possible in our winters.