For a long time i put way too much emphasis and importance on having an oil as thin as possible when cold and always preferred 5w40 vs 15w40 even if temps here almost never go below 0c (32f). I realized that there's no difference at freezing and above between a 5w, a 10w and a 15w in how fast the oil reaches everything and that "wear" or the lack of it will be identical. However, all my gas cars are converted to run E85 and usually they're on the verge of not starting, i sometimes have to add a few liters of gas to my tank if i want them to start at the first key turn, which i always do during the colder months (under 10c). My question is, how much of a factor will be the thickness of the oil (say 1200 cSt for a 15w40 vs an 700 cSt for a 5w40) in the car starting or not? Here's a link to a thread i just read :
Startability vs. viscosity
- Thread starter OM605
- Start date
How did my ole 49 Chevy Deluxe ever start in the minus teens on 30 SAE?
If your vehicles are on the “verge of not starting” above freezing, you need to repair them. The oil is not the problem.
That is all.
That is all.
Let me reformulate : Is there a difference in how fast the starter will make the engine turn between the two viscosities? Is there much more drag with say 1200 cSt vs 700 or is it irrelevant? I am just curious. With E85, anything below 13c can make a difference in how well the car will start, especially with some blends.
Sounds like where you're sourcing your E85 doesn't add the correct RVP gasoline. The whole point of the 15% gasoline is to be ignitable during cold starts.
How were your cars converted? Bigger injectors? PCM recalibrated? Fuel sensors added? How does it sound when cranking over? Cranks fast? Does it sputter?
How were your cars converted? Bigger injectors? PCM recalibrated? Fuel sensors added? How does it sound when cranking over? Cranks fast? Does it sputter?
In europe cars a almost always converted with conversion kits (with an ethanol content sensor in my case). In my case it starts absolutely perfectly just like it would with gas but in some cases it won't start at the first key turn or will sputter for a second and die and a second key turn makes it start perfectly (hence the fact i always add a few liters of gasoline to always have a smooth start from december to february when it is around 5c). It feels like every rpm the starter can give will count as well as the less possible drag on the engine to achieve a perfect smooth start sometimes.
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Your “problem” is not the oil.
If you still persist in believing that it is, then use a 30-grade. Problem solved, or at least confirmed.
Yes the thicker oil can reduce cranking RPM but not enough to matter. You just need an ignitable, ignited mixture for a few cylinders and then cranking is no longer needed.
Odds are that either your injectors need cleaning, battery is weak, or plugs or wires need replaced. If you've done all that, your ignition coil(s) might be on the way out.
If merely putting a bit more gasoline in to up the % solves this, why not just do that if it is only occasional in winter's lowest temperatures?
Odds are that either your injectors need cleaning, battery is weak, or plugs or wires need replaced. If you've done all that, your ignition coil(s) might be on the way out.
If merely putting a bit more gasoline in to up the % solves this, why not just do that if it is only occasional in winter's lowest temperatures?
New battery, new sparkplugs, almost new coils and wires. In fact my car starts pretty good on E85 compared to most i've seen. I never had a poorly maintained car that didn't start perfectly, I had the occasion to start my C180 at -15c on gas and that was with 15w40 in the sump when i bought it two years ago it and felt like i didn't have to even the key to start it haha. This is more out of curiosity than anything else.
So try a 30-grade and report back.
no factor as the reason the E85 refuses to start is the evaporation and flammability of ethanol when cold.
Maybe you can fit glow plugs in the intake (before the throttle valve) to heat up the intake air.
It was probably that robust 6 volt battery system that did it!
Don't tempt me. I have some 20w50 that i need to use.
20w-50 is excellent top off oil...
I will probably just use it for top offs as i'll never have the guts to do a full oil change with it.
Of course there will be more engine load at start-up with a thicker oil because of more shear drag in the oil layer between moving parts. But the difference between 1200 and 700 cSt isn't really that much and shouldn't make any real difference in cranking speed if you have a healthy starter and battery. If it was the difference between say 3000+ cSt and 700 cSt then you'd probably be able to see a distinct difference in cranking speed.
Thanks for your answer, this is what i was looking for!
E85 is your problem. Not the best in cold weather
I wonder if its a compression ratio issue? I know E85 on the newer GTDI's can get them to MBT even with compression ratios as high as 12:1.? So apparently you can run north of 12:1 and still be taking advantage of the "octane" provide by E85.
I am not familiar with the cars in your sig so I could totally be making things up.
I am not familiar with the cars in your sig so I could totally be making things up.
