Some questions about cold start with dino vs syns

[mikeg5]

ok i am asking these questions for some folks on another board.. so here it goes

1.what is the difference in a syn oil vs dino oil when cold (at start up) and the protection properties that go with it??


2.Do syns cling to metal parts better when cold (start up)?

3. what is the proper way to warm up a motor when its 15 degrees or colder? better yet any ambient temp outside?

4. would a motor filled with synthetic oil be bogged down on a cold start morning lets say 8 degrees F?? even with a new battery?

i ask these questions (seriously) bc some folks i think have the wrong impression of how syns work in colder climates compared to the dino counterparts.. thanks guys in advance..

 

[Quest]

Here are my 2c's worth:

(1) proper viscosity goes a long way RE: winter cold starts, and to my understanding so far, not much difference in protection during startup between syn and conventional oil (remember: if it's ILSAC GF-4, it's already semantically a "blend"). Of course, the only difference is that given that syn of the same viscosity/weight tends to flow better than conventional oil of the same weight/viscosity given a paricular temperature, you get faster flow to the critical parts during initial cold start ups, which maybe translated to as "less wear"...

(2) oil that is polar in nature will cling better....syn, depending on the blend and such, the degree of polarity differs from one blend/brand to another.

(3)I just fire it up and let it idle for a few mins...no more than 5 when it's down to -20C, and no more than 8mins if it's down to -30C or below (provided that I can fire up my EFI'ed car that has no battery blanket and no block heater)

(4)this question is reflective of point #1 so I must say that given the same viscosity requirements, if you happen to be using a syn blend that is less viscous than that of conventional oil of the same weight/viscosity under the same operational temperature, syn will crank faster and get you up quicker, so long as there's enough juice in your battery and strong enough spark (also proper cold-start F/A mix provided by properly functioning/tuned EFI cars).

Remember this: I have my 1991 323 B6 block fired up @ -38C w/o block heater and battery blanket with just Q-state syn 10W30; and I was also able to crank over my suzuki 3-cyl carb'ed engine @ -32C, with conventional oil (10W30), w/o block heater nor blanket.

Q.

 

[Kruse]

Originally Posted By: mikeg5
3. what is the proper way to warm up a motor when its 15 degrees or colder? better yet any ambient temp outside?

4. would a motor filled with synthetic oil be bogged down on a cold start morning lets say 8 degrees F?? even with a new battery?



I'm not going to get into any scientific data, just my own observations. If you want to see a difference between dino and synthetic, just take a quart of dino and a quart of synthetic, both having the same viscosity, and put them in a your deep freeze overnight. Then pour them side-by-side and see which one pours easier. Your car's engine sees the same difference.

 

[hate2work]

Originally Posted By: Kruse
Originally Posted By: mikeg5
3. what is the proper way to warm up a motor when its 15 degrees or colder? better yet any ambient temp outside?

4. would a motor filled with synthetic oil be bogged down on a cold start morning lets say 8 degrees F?? even with a new battery?



I'm not going to get into any scientific data, just my own observations. If you want to see a difference between dino and synthetic, just take a quart of dino and a quart of synthetic, both having the same viscosity, and put them in a your deep freeze overnight. Then pour them side-by-side and see which one pours easier. Your car's engine sees the same difference.


Just watch this video...you'll see why synthetic has an advantage over dino when it's cold.

http://www.youtube.com/watch?v=gKtxqf5OFTU

 

[IndyIan]

Originally Posted By: Quest
Here are my 2c's worth:

(2) oil that is polar in nature will cling better....syn, depending on the blend and such, the degree of polarity differs from one blend/brand to another.


I was wondering if this is why some people have noisy startups when they switch to Mobil1 synthetic? The oil perhaps drains so easily from bearings?
I don't think oil can be polar in the molecular meaning but I'm sure there are oil with different levels on clingyness. The extreme being chainsaw bar oil...
I do wonder if some dino oil does cling more than synthetics and maybe better for cold starts before the bearings recieve oil pressure?
I don't think I'm going to add a 1/2 quart of bar oil to my synthetic oil in my cars just yet though!
Ian

 

[mikeg5]

so warming a car up in 8 degrees by letting it idle for about 3 minutes and driving it slow or easy till its at operating temp isnt the way to do it

 

[wcbcruzer]

Originally Posted By: mikeg5
so warming a car up in 8 degrees by letting it idle for about 3 minutes and driving it slow or easy till its at operating temp isnt the way to do it


That sounds good to me.

 

[hate2work]

Originally Posted By: mikeg5
so warming a car up in 8 degrees by letting it idle for about 3 minutes and driving it slow or easy till its at operating temp isnt the way to do it


I'd say generally speaking that would work well.

Variables would include syn oil or dino oil? parked outside? parked inside? heated garage?

 

[demarpaint]

Originally Posted By: mikeg5
so warming a car up in 8 degrees by letting it idle for about 3 minutes and driving it slow or easy till its at operating temp isnt the way to do it


I'd say that would work fine. I mentioned in another thread I let the engine run until it gets to just under 1000 rpm and drive away slowly. It works well for me where I live. Generally about 2 minutes, the older 4.9L Ford took about 3 minutes I timed it this afternoon when it was about 10*F. The Aerostar took +/- 2 minutes at 7*F this morning..

HTH

 

[MolaKule]

Quote:
would a motor filled with synthetic oil be bogged down on a cold start morning lets say 8 degrees F?? even with a new battery?


By bogged-down, I assume you mean excess drag due to the cold temps.

A pure dino will have wax crystal formation at higher temperatures whereas synthetics will still be liquid and flowable. Now there is a chemical that lowers the pour point:


Quote:
Pour Point Depressant (Performance Additive): polymethacrylates (PMA's); reducing wax crystal formation and increases solvency of oil at low temperatures. May be part of VII package.


http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=530321#Post530321

Wax crystals means little or no oil flow and increased drag for mechanical components.

Now PCM0's called "Synthetic Blends" have synthetic oils, in the amount of 5 to 20%, mixed in with them to lower the pour point.

http://en.wikipedia.org/wiki/Pour_point

For example: This morning it was -35F and the Mobil 1 10W30 HM was very liquid.

The MotorCraft 5W30 (a Blend) was liquid as well, but much thicker than the synthetic 10W30.

Check out the pour points of Rdline:

http://users.forthnet.gr/ath/mesastoura/Motor_Oil_PDS_10-08.pdf

 

[ryan2022]

I'm not a huge beleiver in Synthetic, but cold start protection is one area I have to say it makes a significant difference.

It seems that pretty well any synthetic will have better cold pour properties than a straight dino. Semi synthetics usually are noticeably better as well.

Thats not to say that there arent some dinos that do well in the cold temps. 5W30 Pennzoil YB pours down to -39 C. Thats close to synthetic territory.

 

[labman]

Originally Posted By: IndyIan
Originally Posted By: Quest
Here are my 2c's worth:

(2) oil that is polar in nature will cling better....syn, depending on the blend and such, the degree of polarity differs from one blend/brand to another.


....
I don't think oil can be polar in the molecular meaning but I'm sure there are oil with different levels on clingyness. ....


An ester based synthetic will be more polar and should cling better. A PAO will still be completely non plar.

 

[jldcol]

I don't think the oil has all that much effect on starting, because there is not really any oil flow during a really cold temp crank, any this may not even prime up the oil pump. Much more important is the battery condition (temp/and state of charge), the cables and conections to the starter, and the starter solenoid and internal resistance. You also need dry fuel that easily vaporized, and a well timed hot spark. I say there is essentially no oil flow by how long to shut off oil light, after it fires up 3-5 sec, and thats at ~800 rpms, so I don't see how 150-200 cranking rpm will move all that much oil, espically seeing how thick it is at that temp. This is a dry type condition at the startup, so I see why you are curious about the film cling.

 

[Bill in Utah]

15 degrees above is nothing.

15 below is nothing for today's oils. This is one area where you DO see a DIFFERENCE between yesterdays and today's oils is in well below zero performance.

My 86 Jetta with well over 330k miles on it has seen mostly 10w-30 and 5w-30 in the below zero weather and once SL oils came on line big difference in starting.

The SM oils (5w-30 and 5w-20) have excellent cold start properties.

When starting my engine, I start it, wait maybe 30 secs and drive away. The engine warms up quicker and much better driving it than sitting idle.

Using a scan gauge, the engine is at a higher temp in 5 minutes of operating than 15 minutes of idle. Plus you are getting something for the use of the fuel.

People who "warm up" by idling their engines for 10-15 minutes then getting on it because they feel it is warmed up are fooling themselves.

Like others, battery health and coolant is more important than what type of oil you use until you are below 30 IMO. (as along as the oil is a SL/SM 5w-x oil)

Take care, Bill