Stihl 025 Won't Start When Warmed Up

[hallbax]

Although I have read things here many times, this is my first post. I have a Stihl 025 that I purchased new some time ago. Lately it has developed this annoying habit - it will start great from a cold start, but after it runs for a few minutes, if I let it stop, it will not restart. I have to let it sit for a long time before I can get it to run. Any ideas? As it stands now, I have to start it, keep it running, and cut as much as I can before I shut it off, because I sometimes cannot start it for an hour or more. If I leave it overnight, it will start right up. I am baffled.

Thanks. Nice site.

 

[Lakeside53]

Most likely your tank vent is blocked. Try loosening the cap (don't fill the tank!) next time and see what happens.


other:
- carb
- ignition module

 

[stihl025]

I had this happen one time when my spark plug was going bad. Had a crack in the insulator that expanded when hot, wouldn't start back up. Try putting a new Bosch in it and see what happens.

 

[sugarbush]

next time it does it, pull the plug to see if it's wet. if so the carb is leaking--
put in a kit and make sure to set the needle to spec.

 

[mountainlake]

First guess would be with surgerbush, try holding the throttle wide open when cranking. Lakeside, tank vent is easy to try but shoud be dieing when your running it and if partially clogged shouln't take over 10 minutes to restart. Same with the coil, it should die when running it. Cracked plug could happen and doesn't cost much for a new one. Steve

 

[scotclayshooter]

next time it does it, pull the plug to see if it's wet. if so the carb is leaking--
put in a kit and make sure to set the needle to spec.

JUst a nice simple thought check the gap on the plug i had hot start problems on a fs250 all it turned out to be was too large a gap
Yes thats right i bought new plugs but never checked the gaps!
Funny thing was if i switched it off with the choke instead of the switch it would start right up

 

[mountainlake]

JUst a nice simple thought check the gap on the plug i had hot start problems on a fs250 all it turned out to be was too large a gap
Yes thats right i bought new plugs but never checked the gaps!
Funny thing was if i switched it off with the choke instead of the switch it would start right up

That would make sence, a liitle weaker spark when hot can't jump a wide gap. Steve

 

[Lakeside53]

Lakeside, tank vent is easy to try but shoud be dieing when your running it and if partially clogged shouln't take over 10 minutes to restart.

Not so true... when you are running the saw the gas is vibrating and that creates a vapor pressure. When you stop, the gas vapor condenses and a slight vacuum in the tank is formed. I see it all the time. Sometimes you can get them to start by just shaking the saw violently..

 

[Lakeside53]

JUst a nice simple thought check the gap on the plug i had hot start problems on a fs250 all it turned out to be was too large a gap
Yes thats right i bought new plugs but never checked the gaps!
Funny thing was if i switched it off with the choke instead of the switch it would start right up

????? The plugs come pre-gapped... at least the correct plug does...

Starting after killing with choke just indicates that you needed a richer mixture to get it started. Carb settings, seals etc..

 

[mountainlake]

Although I have read things here many times, this is my first post. I have a Stihl 025 that I purchased new some time ago. Lately it has developed this annoying habit - it will start great from a cold start, but after it runs for a few minutes, if I let it stop, it will not restart. I have to let it sit for a long time before I can get it to run. Any ideas? As it stands now, I have to start it, keep it running, and cut as much as I can before I shut it off, because I sometimes cannot start it for an hour or more. If I leave it overnight, it will start right up. I am baffled.

Thanks. Nice site.

Let us know if it starts right up after taking the cap on and off. Steve

 

[scotclayshooter]

????? The plugs come pre-gapped... at least the correct plug does...

Starting after killing with choke just indicates that you needed a richer mixture to get it started. Carb settings, seals etc..

Stihl dealer supplied plugs cant remember what make but they were not ngk and they were gapped at 1mm not 0.6mm
I didnt do any thing different after gapping the plug i took out and no problems ever after that
the hot start problem was why i did the muffler and the carb.
thanks to you guys!

 

[Lakeside53]

Hmmm.. you mightewant to have talk with that "dealer"..

 

[scotclayshooter]

Hmmm.. you mightewant to have talk with that "dealer"..

LOL they dont inspire confidence Thats for sure
lucky they had any plugs!
I paid £7.05 for 2 NGK bpm7a
on the same day i asked at local motor factor and came out with 4 for £5.77 grr
£24.42 $45.60 for a 036 carb parts kit 11280071065
what would that cost over with you?

 

[stihl025]

Update?

Hallbax,

Have an update yet? I think were all curious to find out what the solution was...

 

[Lakeside53]

LOL they dont inspire confidence Thats for sure
lucky they had any plugs!
I paid £7.05 for 2 NGK bpm7a
on the same day i asked at local motor factor and came out with 4 for £5.77 grr
£24.42 $45.60 for a 036 carb parts kit 11280071065
what would that cost over with you?

LOLOLOL We pay about 80 cents in 100 lots for the NGK (retail $2.50 to $3)...

Carb kit for a Zama C3A? about $5 or so.. retails about $12.50. Even Stihl's version 0000 007 1079 is only only $20. or so. Nobody ever buys or resells the 1128 number - that's $33! Mail order - $4-7.


It's pretty much always been $ for Pounds.... but looks like it's getting worse, even with $2 for a Pound..

 

[hallbax]

Update - no update

Sorry guys - it's too dang cold to mess with it - an the wife does not like me to try running it in the house. I will give it a go later this week and let you know. This snow is getting out of hand - had to plow the drive three times after the snow stopped falling. It sure likes to blow here in Iowa.