Briggs & Stratton 650 Series - warm weather start only

[cakmn]

I've owned a woodsplitter for about 12 years and it works great. Much easier for an old guy than the splitting maul that I used for decades.
The splitter has a B&S 650 series engine that generally starts easily and runs well. BUT it only starts at or above 50°F. WHY?
At 50° it might take 6-8 pulls to get it going. At warmer temperatures (55 or higher) it will generally start with 1-2 pulls.
Once it's warm from running, it always restarts with a single pull. It always runs smoothly with plenty of power even when the wood is tough.
What might be causing it to NEVER start below 50°F, no matter how many pulls I give it?
It has behaved this way ever since it was new. Most of the time it's no problem at all. But once in a great while, I would like to be able to split a little wood when the temperature might be down in the 30s or 40s. Any helpful hints would be much appreciated.
I've asked on other forums in the past but never gotten any replies to my question.

 

[ILENGINE]

It comes down to the engine being jetted for warm weather, and the choke may be setup to operate at warmer tems therefore the choke doesn't cause enough air intake restriction for starting in cold weather.

I have a customer with a Toro Z turn that has a Kohler Courage engine that I always show up with a can of brake cleaner to use for starting fluid to start that engine for the first time in the spring when I pick it up for spring service. That engine will not start below 50 degrees and it doesn't matter how much you crank or choke it.

 

[cakmn]

It comes down to the engine being jetted for warm weather, and the choke may be setup to operate at warmer tems therefore the choke doesn't cause enough air intake restriction for starting in cold weather.

I have a customer with a Toro Z turn that has a Kohler Courage engine that I always show up with a can of brake cleaner to use for starting fluid to start that engine for the first time in the spring when I pick it up for spring service. That engine will not start below 50 degrees and it doesn't matter how much you crank or choke it.

Thank you for that. So, are you suggesting that the only "fix" for my warm-weather-only engine is to use starting fluid if I want to use it in cooler weather?
I just realized that in my original post I forgot to say that not only does it not start, it won't even fire the least little bit.

 

[ILENGINE]

Sometimes you can improve the starting by either replacing the choke plate with one designed for colder temps. or I have modified choke plates by closing off some of the holes in the plate to make them more restrictive. Like that Kohler I discussed I actually filled two of the four holes in the choke plate to make it more reliable to start.

Some of the push mower engines are designed to operate at temps above 70 degrees. Good luck trying to start one at fall 40 degree temps.

 

[cakmn]

Sometimes you can improve the starting by either replacing the choke plate with one designed for colder temps. or I have modified choke plates by closing off some of the holes in the plate to make them more restrictive. Like that Kohler I discussed I actually filled two of the four holes in the choke plate to make it more reliable to start.

Some of the push mower engines are designed to operate at temps above 70 degrees. Good luck trying to start one at fall 40 degree temps.

Thank you for the additional info. I'll consider this through the winter and maybe experiment come spring. This makes me wonder, though, why they would have sold me a woodsplitter with an engine intended for warm weather use – I'm in far northern Minnesota. But being where I am, I think it's not worth trying to start my B&S anymore this year. Our temperatures are currently fluctuating between highs in the mid 30s and lows down into the teens and single digits, and only working their way lower as the ground here turns white. Eventually we will be seeing temps down into the -30s and -40s for a while before the Sun once again rescues us, as it always does. We'll be happy if our cars and trucks start through the winter. Thanks, again, for your help.

 

[StarTech]

Plus it could simply that valves needing adjusting as colder temps usually lowers the starting compression and with valve just barely closing it may cause starting issues.

If I remember the 650 series are L-head engines.

 

[lemen]

Is there no option to heat up the engine before starting, with a hairdryer or something?

 

[callwill]

Back in the days when you could buy an incandescent light bulb my father would hang a trouble light next to a motor to keep it warm for easier cold weather starting

 

[lemen]

I use sometimes a 500Watt halogen working light for that!

Of topic: I had once a whole in a cilinderhead of a car. (Had a broken bolt, but drilled out the wrong spot)
Repaired it with defcon-C. Put two working next to the engine covered with (wool!) blankets, because it was to cold.
It worked.

 

[BigTermite]

I've used a heat gun to get mine to start in the cold. I pull the plug and heat the combustion chamber directly until good and warm. Reinstall the plug, she hits on one pull. Anything above freezing, not needed for mine.