026 - Died when stump cutting

[Clarkbug]

Hey all.

So looking to try and get some confirmation on my troubleshooting approach for my 026.

I had posted on here a couple years back by now about how I needed to freshen it up since I had bought it with a carbon scored piston, but it had run great for me. Had the realization that was over 15 years ago now... Anyway, I had a couple soft maples to drop and thought I would give it a little run time. Dribbled a little gas in the carb and it fired right up and ran great. Used the saw over two days for felling and bucking, and no issues other than I could see a little smoke, but didnt think anything of it. Was finishing up the last cut which was a stumping cut, and the saw started out fine, then just bogged and quit. Checked the tank and was almost out of fuel, so thought that was the problem. Filled up, got it going, and the problem persisted. Would fire up, but then would die as soon as I went sideways. Let it sit, and then tried to make one more limbing cut, and it would start and die, or would run on choke for a second or two, but would die off fast idle.

All that said, Im guessing its either a fuel line/fuel filter issue, pulse line, or a bad seal. Is there anything else that I should be checking or look out for? I know the seals on these can be a real pain to deal with, so not looking forward to that part of things.

Appreciate any thoughts/input you can offer.

 

[hacskaroly]

Would fire up, but then would die as soon as I went sideways.

Pressure testing should help you narrow it down, but with the saw dying when you flip it on its side I would suspect air leak from that oil seal. You can test that if you can get the saw running, spray some non-flammable break cleaner on the side of the suspected air leak, if there is one, it will suck in the break cleaner and the saw will stop running (won't hurt the saw) and this will confirm where the problem is. Due to the age of the saw the oil seals may be stiffinging up some.

I had an 034 I was working on recently, did the same thing, tip it on its side and it would shut off. I found one of the bearings was wobbly too, so I just went ahead and split the case, replaced the bearings and put new oil seals in.

 

[Clarkbug]

Pressure testing should help you narrow it down, but with the saw dying when you flip it on its side I would suspect air leak from that oil seal. You can test that if you can get the saw running, spray some non-flammable break cleaner on the side of the suspected air leak, if there is one, it will suck in the break cleaner and the saw will stop running (won't hurt the saw) and this will confirm where the problem is. Due to the age of the saw the oil seals may be stiffinging up some.

I had an 034 I was working on recently, did the same thing, tip it on its side and it would shut off. I found one of the bearings was wobbly too, so I just went ahead and split the case, replaced the bearings and put new oil seals in.

Thanks for the quick response here.

In the past, I thought there was an issue because of my sorta scratched piston (carbon scoring from a previous owner), so I figured the compression was low. This is the first time I have had the issue with running on its side. Ill need to get my workbench cleaned off and will check the rubber bits and see if I can pressure/vac test it. I hope its not a bad bearing, cause if it needs to be split Ill be asking to see who here on the forum wants to take that on for me...

 

[hacskaroly]

I hope its not a bad bearing, cause if it needs to be split Ill be asking to see who here on the forum wants to take that on for me...

It's not a hard process when you have the right tools. I had split three cases and replaced bearings and oil seals without the right tools and it was nerve-wracking. Though the tools can be a little pricey, defiantly well worth it if you are going to split multiple cases at some point!

 

[Wonkydonkey]

I,m wondering if it’s lean Seized, due to the fact you said ,….

Was finishing up the last cut which was a stumping cut, and the saw started out fine, then just bogged and quit. Checked the tank and was almost out of fuel, so thought that was the problem. Filled up, got it going, and the problem persisted. Would fire up, but then would die as soon as I went sideways. Let it sit, and then tried to make one more limbing cut, and it would start and die, or would run on choke for a second or two, but would die off fast idle

I guess you could have a look at the piston. But it sounds like you won’t be able to get it running to spray the brake cleaner on the pto seal.

It’s a choice your have to make, either p&v it or pull the jug and see if it’s salvageable and then go from there..?

 

[Clarkbug]

I,m wondering if it’s lean Seized, due to the fact you said ,….

Was finishing up the last cut which was a stumping cut, and the saw started out fine, then just bogged and quit. Checked the tank and was almost out of fuel, so thought that was the problem. Filled up, got it going, and the problem persisted. Would fire up, but then would die as soon as I went sideways. Let it sit, and then tried to make one more limbing cut, and it would start and die, or would run on choke for a second or two, but would die off fast idle

I guess you could have a look at the piston. But it sounds like you won’t be able to get it running to spray the brake cleaner on the pto seal.

It’s a choice your have to make, either p&v it or pull the jug and see if it’s salvageable and then go from there..?

Boy I hope not... But Ill have to pull the muffler and take a look.

 

[hacskaroly]

But Ill have to pull the muffler and take a look.

If there is scorring, then it could still indicate a bad oil seal. I have an 046 that did this. It was a dump find saw, I should have replaced the oil seals before putting it into service!

 

[Woodwackr]

pull the muffler and check for scoring but it sounds like it could be a bad fuel filter.

 

[cuinrearview]

I don't think I'd be hoping to keep running a saw that was carbon scored and not fixed, then ran for 15 years. You need to give this saw some attention.

 

[Clarkbug]

I don't think I'd be hoping to keep running a saw that was carbon scored and not fixed, then ran for 15 years. You need to give this saw some attention.

That's the plan now at least before I do any more damage to it.

Started to look into it a little bit tonight. Fuel line definitely needs replacing. It's pretty gummy in there. Guessing this is a case where OEM works best, or do folks cut the grommet and feed in some Tygon instead?

Found my ground wire had been rubbing on the cylinder so will need to tape or replace that.

My muffler gasket had decided to leave the chat, so I had an exhaust leak where I couldn't see it and didn't realize it. No idea how long that's been going on, but longer than it should have.

That's what my piston looks like, so it's time for sure to swap the new one in.

I will clean up the saw a bit then see if I have the stuff to try and pressure test it before replacing other parts. I'll do the pulse line too while I'm in here.

 

[Woodwackr]

That's the plan now at least before I do any more damage to it.

Started to look into it a little bit tonight. Fuel line definitely needs replacing. It's pretty gummy in there. Guessing this is a case where OEM works best, or do folks cut the grommet and feed in some Tygon instead?

Found my ground wire had been rubbing on the cylinder so will need to tape or replace that.

My muffler gasket had decided to leave the chat, so I had an exhaust leak where I couldn't see it and didn't realize it. No idea how long that's been going on, but longer than it should have.

That's what my piston looks like, so it's time for sure to swap the new one in.

I will clean up the saw a bit then see if I have the stuff to try and pressure test it before replacing other parts. I'll do the pulse line too while I'm in here.

Judging by the crud level shown it’s time for complete disassembly and rebuild.
Or, seal up the intake and exhaust and pressure wash the little sucker.

 

[Clarkbug]

Judging by the crud level shown it’s time for complete disassembly and rebuild.
Or, seal up the intake and exhaust and pressure wash the little sucker.

Ill spend some time cleaning it up before tearing into it any farther. Should be a little bit cathartic if I can get some tunes going and some time in the evenings to work away on it. Once I can see some things, Ill get some photos of what the inside of the cylinder looks like, and hopefully it will clean up OK.

Its been a bit since I have been in a Stihl IPL. Do the * just mean that a part has been superseded?

 

[hacskaroly]

Ill spend some time cleaning it up before tearing into it any farther. Should be a little bit cathartic if I can get some tunes going and some time in the evenings to work away on it.

If the parts you take off have carbon build up, let them soak in Seafoam, that will soften up the carbon and make it much easier to get off. As for the IPL question, do you have a screenshot of the document in question with the * ?

 

[Wonkydonkey]

Iirc, the * mean there is a change in parts and there will be a date &/or serial number
The date (week, yr) and the serial number it was changed. And x is the first number which is different depending on where the saw was made

But if your unsure post it up and someone will chime in

Btw this is from the 026 ipl

 

[el33t]

Iirc, the * mean there is a change in parts and there will be a date &/or serial number
The date (week, yr) and the serial number it was changed. And x is the first number which is different depending on where the saw was made

But if your unsure post it up and someone will chime in

Btw this is from the 026 ipl

View attachment 452813

Rather, this information in the IPL with the number.year format refers to the designation of the technical information document in which the change is described. The document will contain information from which serial number the change will be/was made.

 

[Clarkbug]

Thanks for the IPL explanation! That makes sense looking at it now, but my brain definitely wasn't going to get there on its own.

 

[Wonkydonkey]

Rather, this information in the IPL with the number.year format refers to the designation of the technical information document in which the change is described. The document will contain information from which serial number the change will be/was made.

yes You are korrect, I had forgotten what the date part really ment in the ipl.
Thanks

 

[Coupe]

Looks like it could do with a good clean up. If the wire from your start/stop switch is that
bad either tape it for the time being or replace it. Also if you have a good preassure tester like
a mityvac 8500 what I do is take the tank filter off off and plug straight into there. That will test if
you have a faulty fuel line or your carburetor is dropping preassure. But that does not always works
cause quite often be in need of a carby clean and new kit. I side with the rest of the guys on here it is an
older saw so could be the seals are a bit past it. I have had some saws left with me at times that have been
scored way worse that that and still ran but had started to lack power. I would most certainly fix the start/stop
wire though as it only wants one thread of wire sticking through and that's enough when you lay it
on it's side to stop it. If you never rebuilt the carb may pay to start there as your fuel line carby area sounds a
bit suspect to me.