Cold weather vs. Warm weather and fuel

[ShawnAgne]

Gotten cold here in Ohio and noticing somthing.

When its warm both the Cub and 300 start right up. But as it gets cooler 50s, 40s, especially when its in the 30s or colder they both start but sputter a lot more and need more playing with the choke then when they warm up they run fine.

So like my other thread been just thinking about stuff today and one of the things I was wondering is in the cooler/colder temps is the issue I'm seeing due to the fuel volatility? If so would non-ethanol gas be a better choice in the cold temps? Or is this just the life of old tractors and is what happens?

[Lt.Mike]

That’s just life with a carbureted engine.
Modern engines use fuel injectors, sensors and a computer. With a carb there’s just that God given computer we were all born with.
I don’t think these engine cars too much about what grade of fuel runs through them.

[Gary S.]

Like in the other thread my dad bought the 49 in 1960 supposedly rebuilt by the dealer. Still 6v. We can now only buy ethanol gas,over the years I have not noticed any starting difference. Matter of fact the fuel in it now has to be a year old but has been treated with marine stabil. When 50+ degrees starts anytime just like it had been shut off. The real problem is the updraft carbs - anything that ever has used them has had cold start problems and that's why manifold heat is your friend when it's cold IMHO

[ShawnAgne]

Ok, thanks. One of those things I was thinking about today.

[BigBill]

How about the oil weight? Summer oil and winter oil?

[ShawnAgne]

I run the 15-45W diesel fleet oil year round.

[inairam]

I use STA-BIL 360 (22239) Marine Ethanol Treatment and Stabilizer it is blue, not red. It is supposed to have enzymes that reduce the ethanal. I use it in my cubs and my generators mostly in the winter. I add it the gas cans. I think it helps but I do not have the same cold weather others have.

[Stanton]

Here in Missouri, winters are basically cold all season, with periods of intense cold when a front passes through (and warm spells too). I use straight gas—no ethanol with Sta-Bil.
I do notice it takes longer to start in winter, but attribute that to several factors. Gasoline may be a contributing factor, but oil weight, the air temp, the humidity, condition of points, plugs, etc. all weigh in.

[Gary S.]

Up until about 7 years ago I always changed over to 10w in the winter now I don't bother-it's 10-30 all year. Try the heat gun on the manifold, you will be amazed on how easy it is,your not draining oil and keeping it in the house,your not bringing the battery in. Your at most using a short extension cord and standing there for 3 minutes. A real KISS principle- once the engine is running the exhaust automatically heats it.

[ShawnAgne]

Thanks everyone for all the ideas.

[Lt.Mike]

I run the 15-45W diesel fleet oil year round.

If I’m right that has zinc added like Mobil 1 15-50.

[Matt Kirsch]

Cold air is denser, causing the air-fuel mixture to be leaner, hence the need for more choke at startup in colder temperatures. Choke richens the mixture, less air, more fuel.