Stihl 025

[mdavisfps]

Hi,
I'm a homeowner, not a professional, and cut down & cut up approx. 4-5 trees per year (14"-28" mixed oaks).
Some years I don't cut any.

Anyhow, I have a Stihl 025 which starts easy, runs well, and is no problem starting back up when hot -- UNLESS I let it sit for about 10-15 minutes after having run it for awhile. Then it won't start or even fire no matter what setting I try (hot/cold switch) or how many times I crank it.
However, if I remove the spark plug and crank it a few times and then replace the spark plug, it will start with the first pull (on the hot setting) and then run well after that. I thought maybe I had flooded it while trying earlier to get it to restart, but the spark plug is dry.

The saw is 25 years old. The Stihl dealer says that at that age it could be any number of things, e.g., a fuel diaphragm, or other parts of the carburetor, or the fuel line, etc.. Cranking it without the spark plug causes it to crank a lot faster, which probably corrects the problem, which then allows it to restart. He says that I could spend $50-$100 dollars to repair it, but if it was him, he would replace it with a comparable saw, like the MS 250. He says that if I've gotten 25 years out of it, then I've gotten my money's worth, and I see his point.

I'm was just wondering, however, if someone on this site might know something more specific in regards to the symptoms of this problem.

Thanks,
Mark

 

[HarleyT]

First, look at the fuel line closely for cracks.

 

[mdavisfps]

First, look at the fuel line closely for cracks.

Will do. Thanks Harley. Had to replace that once before.
Mark

 

[dougand3]

And before you buy a carb kit, consider that a new AM carb is $8-$9 online. Lots of cheap 025 parts available - you can rehab the saw to proper running.

 

[mdavisfps]

And before you buy a carb kit, consider that a new AM carb is $8-$9 online. Lots of cheap 025 parts available - you can rehab the saw to proper running.

Great information. Thanks, Doug.
Mark

 

[HarleyT]

And before you buy a carb kit, consider that a new AM carb is $8-$9 online. Lots of cheap 025 parts available - you can rehab the saw to proper running.

Nah, just get a real Walbro from your local Stihl dealer for $21.49. It is not Chinese junk and fully adjustable.
#1123 120 0605

 

[mdavisfps]

Nah, just get a real Walbro from your local Stihl dealer for $21.49. It is not Chinese junk and fully adjustable.
#1123 120 0605
View attachment 509998

Thank you, Harley. Appreciate it. Would probably want to replace the fuel line & filter too, right?
Mark

 

[HarleyT]

Before you start buying stuff, pop off the muffler and take a peek at the piston. Put up a pic of it at the rings/top.

 

[mdavisfps]

Before you start buying stuff, pop off the muffler and take a peek at the piston. Put up a pic of it at the rings/top.

I'll try!
Thanks,
Mark

 

[altair]

First, look at the fuel line closely for cracks.

Second this. 021/023/025 are known for cracking fuel lines, with mine it cracked just by where it exited the fuel tank...cheap and easy to replace.

 

[mdavisfps]

Second this. 021/023/025 are known for cracking fuel lines, with mine it cracked just by where it exited the fuel tank...cheap and easy to replace.

Yes, thanks Altair. That seems to be the first thing to try, since it had happened on mine before.

 

[Mattyo]

Just replaced a line on my father in laws 025....if the saw has been sitting for a bit just replace it. Wasnt too expensive at the dealer. I'd definitely prefer the fully adjustable carb to the one that's on this saw. Overall it seems to run ok ....best with a very sharp chain. I've done a few oaks over the last couple days.

 

[Brushwacker]

I wouldn't rule out the coil being the problem. Things heat up a bit when you shut it off before it actually cools I believe .Often a bad coil works until it reaches a certain temperature . First things first, check the easy stuff first so u can rule them out before doing more difficult and expensive replacements and repairs. I have often found people trying to run with to wide a spark plug gap, be sure it is .020 and if u haven't try a new sp. plug. Fuel line is a common problem but I think the nature of it running well if it is an extended time suggest something else, I expect electrical or possibly your piston has some damage, so after making sure the sp. plug is ok if that doesn't correct it check the piston through the exhaust port as previously suggested. If u know some one with an working 025 u might be able to try parts off it to find your faulty part should the easier things not find the problem.

 

[drf255]

Change your spark plug. It's a cheap and easy experiment and you probably need a new one anyway.

When things get hot, electrical resistance increases.

I once changed around $150 in parts on a Honda 4 stroke. Was the damn $2 plug in the end, all along.

 

[mdavisfps]

Thank you Brushwacker and drf255 for your input. Good things to consider.
Mark

 

[mdavisfps]

Not to say that I don't need new part(s), but the thread titled "562xp Hot start?" I found quite interesting and perhaps relevant to my problem. Think I'll try a minute or so of low-load running or just idling before shutting down next time.
Mark

 

[angelo c]

Hi,
I'm a homeowner, not a professional, and cut down & cut up approx. 4-5 trees per year (14"-28" mixed oaks).
Some years I don't cut any.

Anyhow, I have a Stihl 025 which starts easy, runs well, and is no problem starting back up when hot -- UNLESS I let it sit for about 10-15 minutes after having run it for awhile. Then it won't start or even fire no matter what setting I try (hot/cold switch) or how many times I crank it.
However, if I remove the spark plug and crank it a few times and then replace the spark plug, it will start with the first pull (on the hot setting) and then run well after that. I thought maybe I had flooded it while trying earlier to get it to restart, but the spark plug is dry.

The saw is 25 years old. The Stihl dealer says that at that age it could be any number of things, e.g., a fuel diaphragm, or other parts of the carburetor, or the fuel line, etc.. Cranking it without the spark plug causes it to crank a lot faster, which probably corrects the problem, which then allows it to restart. He says that I could spend $50-$100 dollars to repair it, but if it was him, he would replace it with a comparable saw, like the MS 250. He says that if I've gotten 25 years out of it, then I've gotten my money's worth, and I see his point.

I'm was just wondering, however, if someone on this site might know something more specific in regards to the symptoms of this problem.

Thanks,
Mark

It's a little annoying when a dealer (first sign) says to just replace a running saw because it MIGHT cost too much to diagnose the issue. How about you start with the simple cheap stuff (fuel lines- impulse- carb tune/kit) then let me know you had no clue to begin with and then decided to just change enough parts until you "diagnose" the problem.

 

[mdavisfps]

It's a little annoying when a dealer (first sign) says to just replace a running saw because it MIGHT cost too much to diagnose the issue. How about you start with the simple cheap stuff (fuel lines- impulse- carb tune/kit) then let me know you had no clue to begin with and then decided to just change enough parts until you "diagnose" the problem.

Very true. On the one hand, I sincerely appreciate every single post and suggestion in response to my initial posting. There's a lot of experience and knowledge evident in those posts. On the whole, however, I can see that taken altogether the posts kind of reflect the dealer's initial statement that "it could be any number of things", and I was hoping to avoid costly diagnostics in the shop and/or changing enough parts until the problem is "diagnosed".

After reading the thread from this forum mentioned in my previous post, that's going to be where I start -- allowing the saw to cool down a little before turning it off on hot, muggy days. Buying a new saw because mine's "old" is definitely the least desirable option for me.


Thanks, Angelo
Mark

 

[a. palmer jr.]

Not all dealers are alike but many of them want to sell you a new saw even if yours is very fixable. Any part on that saw can be replaced much more cheaply than buying a new MS250 or 251 whatever. Look at the prices of aftermarket parts on the bay and you'll see. I practically built a MS250 from scratch with AM parts and I'd say it's surprising how well it runs..

 

[Mattyo]

If you are going to play parts darts (my favorite technique) might I suggest the simple and cheap stuff first. New fuel line , filter, plug....carb kit or new fully adjustable carb. Vent line too perhaps. The saw needs this stuff anyway. And you will keep your costs low and rule out the simple things in the meantime.