Chainsaw hard to start after warmed up

[Hipastore]

Sometimes it is an unrealistic expectation on the part of the owner who thinks the saw should start first pull with the throttle closed to the idle position. 2-stroke engines basically do not like to start with a closed throttle so most newer saws have a feature where the throttle is automatically opened when the full choke setting is engaged for cold starting. If a saw won't start when hot with a closed throttle, it can sometimes be remedied by adjusting the idle speed screw and the L screw to achieve a more open throttle at idle with the idle set just below the speed where the chain moves, however, it is difficult to get this setting on some saws and the carb has to be set to the fast idle/no choke setting to get it to start quickly. That's why the fast idle position is provided. If the saw doesn't have vapor lock or some other non-start issue and it won't start after 2 or 3 pulls when hot with the throttle closed, you have to open the throttle or you will be pulling for a long time.

Got it. Thanks for your advice. I will adjust the idle screw on my stihl ms 250.

 

[user 122190]

I am going to buy a new saw when it happens. LOL . Just wanna seek general knowledge about this problem.

Yup. That's why peeps are here. Looking for enablers to justify buying a new saw. Doesn't matter that they bought a new saw yesterday and have one on order. Get a new saw for a reason, any reason.

Me; I try and figure out what's the problem. Perhaps that's my problem. Just buy a new saw.

 

[Hipastore]

You are a troll.

No no. I like saws and I have a Stihl ms 250. That's why I like to talk about general knowledge about saws.

 

[Joisey]

Not positive, but it COULD be the fuel. I have had the hot start problem with small 2 stroke engines, leaf blower, chainsaws (4) weedeater and Lawnboy push mower. After scratching my head I tested the fuel (regular unleaded) and found that instead of up to 10% alcohol, it actually had between 14% and 15% alcohol. Alcohol boils at a low temperature and causes vapor lock.

I bought my fuel at a different station, tested it and it showed 9% alcohol content. Everything started from cold OR hot with ease.

 

[user 122190]

Not positive, but it COULD be the fuel. I have had the hot start problem with small 2 stroke engines, leaf blower, chainsaws (4) weedeater and Lawnboy push mower. After scratching my head I tested the fuel (regular unleaded) and found that instead of up to 10% alcohol, it actually had between 14% and 15% alcohol. Alcohol boils at a low temperature and causes vapor lock.

I bought my fuel at a different station, tested it and it showed 9% alcohol content. Everything started from cold OR hot with ease.

Best answer!!!

How are you checking the % Alcohol?

 

[rogue60]

I hope Hipa is paying you guys good $$ for ya knowledge... is no way Hipa is getting all this knowledge for it's online aftermarket chinese chainsaw parts store for free? nah that definitely isn't what's going on here

 

[Mad Professor]

HIPA seems to be a robot.

 

[Mad Professor]

Best answer!!!

How are you checking the % Alcohol?

My BLAC is 0.00%

 

[TRTermite]

Stretching the needle arm spring raised my pop off pressure in my 025 carbs and so far seams to have fixed my starting when warm after sitting awhile issues.. This was after pulling the spark plug and holding saw upside down Whilst cranking saw to clear cylinder of fuel, it would then start. Posting this for readers with this problem and sincerely looking for options. If this works the coil (Ignition) may not be the issue

 

[PV Hiker]

Sometimes it is just a issue between the ears of the user that causes the problem. It is not the chainsaw problem it is what the user did or can't do that caused it.

 

[Bob Hedgecutter]

No no. I like saws and I have a Stihl ms 250. That's why I like to talk about general knowledge about saws.

Would love to see photos of your STIHL MS 250- with all the trademarks and all.

 

[lone wolf]

Just wanna seek general knowledge. Cus I do not wanna send it to shop when this happens to my stihl ms 250.

But it don't happen to the China saws huh?

 

[lone wolf]

Throw it at a tree, a log or hit it with bigger hammer.
Remember you didn't ask for good advice

Some saws can have that effect on us.

 

[angelo c]

Just wanna seek general knowledge. Cus I do not wanna send it to shop when this happens to my stihl ms 250.

Ok...can you describe your "hot start" procedure...the 025 is a known "flooder" you have to ignore the "choke" after 5/6 pulls no matter what. You may never hear the burp.

 

[lone wolf]

Hard start after warm up might mean low compression. Hipa can take a compression test on that saw and post the results here? Also pull the muffler and look at the rings and piston for damage.

 

[Joisey]

Best answer!!!

How are you checking the % Alcohol?

The test is actually simple to perform.

www.delphiautoparts.com/usa/en-US/resource-center/how-test-alcohol-content-gasoline

 

[Hipastore]

Not positive, but it COULD be the fuel. I have had the hot start problem with small 2 stroke engines, leaf blower, chainsaws (4) weedeater and Lawnboy push mower. After scratching my head I tested the fuel (regular unleaded) and found that instead of up to 10% alcohol, it actually had between 14% and 15% alcohol. Alcohol boils at a low temperature and causes vapor lock.

I bought my fuel at a different station, tested it and it showed 9% alcohol content. Everything started from cold OR hot with ease.

Thanks. So fuel is another factor that will result in this problem.

 

[Captain Bruce]

Need to be a bit more specific with what saw. Depending on the saw there are different tricks to get then to fire up.

This post is started by a chinese person who owns a chinese company, much like farmtec, that sells their off-shore parts, to Americans. They sponsor our American forum, and thats just so nice.......I dare say, dandy!
I think thats great! Clearly, this is just another gag post, meant to humour us all. I mean, really? The person who sells the parts, doesn't know anything about engines? They'd be the source for the solution to begin with. Great fun! Real side-spliter............oh, this is about a chainsaw.

 

[Hipastore]

HIPA seems to be a robot.

Ummm. Absolutely not. lol

 

[Captain Bruce]

Just wanna talk about this question. My saw looks good.

You sell the parts to solve the problem...and you don't know anything about engines? Remember, air and fuel. Whatever you use in China must be as clean and pure as is in America. If you use shetty gas, and cheap oil, your saw won't offer the power its designed for. Likewise, hipppaa, your air quality is 1/2 that of North America. Therefore, a 9th grade science major, here or there, would tell you, the power drops when the saw is run in smoke.................rising from the river.

Be more specific, and we American forum members will cheerfully collectively solve your problem. Start with a new saw.............they are cheap.