Stihl 025 blogging and stalling.

[2broke2ride]

Sorry in advance, this is long winded.
This is a customer saw (again lol) saw appears pretty abused and neglected. He claims he only uses canned fuel (although the other saw I have of his had water in the fuel and a very nasty carb) his complaint was that it would start and run ok for a while then it would stall and not want to restart. It seemed to run ok when I initially checked it out but the fuel line was leaking terrible so I figured since I had to pull the carb to replace the line i may as well put a kit in it.
So i kitted the carb with a walbro kit, replaced the fuel line and the filter. The saw will fire on choke, flip the coke off it will fire again and immediately bog out and die. If I get on the throttle when it fires the second time I can usually get it to rev out but it sounds very lean. And as soon as i let it try to idle it bogs out and dies. I have been back in the carb 4 times. Metering lever is set right, the carb passes pressure test, all passages seem clear. I also pressure tested the new fuel line and tried a second new filter.
And the saw ran better than this before I messed with the carb!!!
Piston and cylinder look great, I have not performed a pressure and vac test. I feel like I have a massive air leak somewhere. What do you all think?

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[dmb2613]

Put a carburetor on it, they are cheap from Stihl $30 list I think

 

[Wood Doctor]

Could be the crank seals but try the carb first. Changing the seals is a PITA by comparison. I ran into something like this with an 025 about 4 years ago and new crank seals fixed it.

 

[SteveSr]

Sorry in advance, this is long winded.
This is a customer saw (again lol) saw appears pretty abused and neglected. He claims he only uses canned fuel (although the other saw I have of his had water in the fuel and a very nasty carb) his complaint was that it would start and run ok for a while then it would stall and not want to restart. It seemed to run ok when I initially checked it out but the fuel line was leaking terrible so I figured since I had to pull the carb to replace the line i may as well put a kit in it.
So i kitted the carb with a walbro kit, replaced the fuel line and the filter. The saw will fire on choke, flip the coke off it will fire again and immediately bog out and die. If I get on the throttle when it fires the second time I can usually get it to rev out but it sounds very lean. And as soon as i let it try to idle it bogs out and dies. I have been back in the carb 4 times. Metering lever is set right, the carb passes pressure test, all passages seem clear. I also pressure tested the new fuel line and tried a second new filter.
And the saw ran better than this before I messed with the carb!!!
Piston and cylinder look great, I have not performed a pressure and vac test. I feel like I have a massive air leak somewhere. What do you all think?

Sent from my SM-G950U using Tapatalk

These also like to leak around the pan seam. Try tightening all 4 main housing engine bolts. If the condition changes you have found at least part of your leak. A saw that old SHOULD be leak tested... before your or the customer burns it up!

 

[2broke2ride]

These also like to leak around the pan seam. Try tightening all 4 main housing engine bolts. If the condition changes you have found at least part of your leak. A saw that old SHOULD be leak tested... before your or the customer burns it up!

Those bolts where the first thing I checked. Thanks.
I will leak check it tomorrow. Worked on it till 9:00 tonight and was pretty frustrated at that point so I walked away from it.

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[Bob Hedgecutter]

So, whomever comes up with the correct diagnosis gets a commission from what you are charging the customer to fix the saw?

 

[HarleyT]

You need to see if the impulse hose has come loose, that is common on this model. To re-attach, remove the starter and use hemostats to better reach the nipple on the rear handle assy.

 

[Henry E]

muffler bolts?