Stihl 026 headache

[Dieselcamino]

Seeing as how there are no published compression figures by Stihl for two cycle equipment, the point is moot.
Now, is there going to be a fix to this saw?

Waiting on parts! And as a bonus to everybody I will borrowing one of the specific compression testers from a friend to do a comparison of the two gauges with the old/new cylinder&piston.

 

[Oletrapper]

And another one
https://www.arboristsite.com/threads/compression-tester-recommendations.344422/#post-7339051
]

I've been using this one for years now. Works great but like anything, you have to keep it clean. Just google it. You can find on ebay, amazon, other sites.

JIFETOR Compression Tester Kit Small Engine Cylinder Test Pressure Gauge Tool...​

 

[Okie]

Dieselcamero:

Keep us posted on your findings?
I think I seen where you have other saws or access to such.
When testing your gauge and the friends gauge do the comparison check on a saw that runs good also and for look for a reading of around approx 135-150psi and keep cranking until the gauge reaches max usually within about or less than 6 fast full pulls or the rope.
Usually a Stihl saw with 115 psi will have a felt weak feedback when pulling the rope as it's coming up on the compression stroke.
When I see a chainsaw or any engine that is indicating low compression, especially really low psi, the first thing I do is make SURE that my test equipment readings are actually correct.
My main point is I've seen guys rely TOO MUCH on compression readings, especially low compression readings on a gauge and blame a saw for low compression issues when the MAIN problem was actually elsewhere.

 

[labans]

They’re having you on mate, don’t waste your time.

I totally get that. Just bringing out some revelation.

 

[Dieselcamino]

UPDATE! Top end rebuild came in the mail today, couldn't hesitate so I got right to it.....
And we have a runner! Definitely needs some carb tuning to get the idle right but we're making plenty of noise now.
With the new cylinder and piston (and decomp valve I may block off later) we are getting around 140psi of compression with my cheapo tester, that come to find has the little tappet for 2 strokes in the tip.

So at the end of the total project consisted of the following:
- Chinese carb- unneeded, cleaning the walbro was satisfactory
- New impulse line/carb tube- probably unneeded
- New coil and plug- needed, original had very strange spark issue
- New cylinder and piston- needed, compression was on the brink of functioning, it was very moody if it would fire at all. Original piston had very light scoring, and rings seemed ok but playing with them on the bench they felt as if they would snag up a bit in their groove. I'm guessing they were at the end of their life.
- Crank seals- 1/2 needed, original ones held pressure for a bit but leaked down eventually.
-Muffler cleaning, not needed in this case.
-Air filter/fuel filter and line- would of done regardless.
- Cheapo tractor supply bar- had it as a spare

Looking back I'm happy I stuck with it, even though it is a 90s saw that will occupy garage shelving for 363 days out of the year I didn't let it get the best of myself. Hopefully this thread will be a saving grace for some other guy down the road.

Much thanks to everyone with their tips, ideas, suggestions, data and encouragement.
No thanks to the few who suggested I throw it out, find someone "competent" or that guy who called me a Russian reporter...

 

[Dieselcamino]

Old piston and cylinder

 

[BrettS]

UPDATE! Top end rebuild came in the mail today, couldn't hesitate so I got right to it.....
And we have a runner! Definitely needs some carb tuning to get the idle right but we're making plenty of noise now.
With the new cylinder and piston (and decomp valve I may block off later) we are getting around 140psi of compression with my cheapo tester, that come to find has the little tappet for 2 strokes in the tip.

So at the end of the total project consisted of the following:
- Chinese carb- unneeded, cleaning the walbro was satisfactory
- New impulse line/carb tube- probably unneeded
- New coil and plug- needed, original had very strange spark issue
- New cylinder and piston- needed, compression was on the brink of functioning, it was very moody if it would fire at all. Original piston had very light scoring, and rings seemed ok but playing with them on the bench they felt as if they would snag up a bit in their groove. I'm guessing they were at the end of their life.
- Crank seals- 1/2 needed, original ones held pressure for a bit but leaked down eventually.
-Muffler cleaning, not needed in this case.
-Air filter/fuel filter and line- would of done regardless.
- Cheapo tractor supply bar- had it as a spare

Looking back I'm happy I stuck with it, even though it is a 90s saw that will occupy garage shelving for 363 days out of the year I didn't let it get the best of myself. Hopefully this thread will be a saving grace for some other guy down the road.

Much thanks to everyone with their tips, ideas, suggestions, data and encouragement.
No thanks to the few who suggested I throw it out, find someone "competent" or that guy who called me a Russian reporter...

You got a runner again, good stuff.

 

[Chevboy0167]

Future reference...

https://www.ebay.com/itm/3932140087...h8lUl51Tlez7Q%3D|clp:2334524|tkp:BFBMroGdgPBf

I got this one but see none in stock now. Works very well..

https://www.ebay.com/itm/STRANDIX-1...-ENGINE-SERVICE-3-HOSE-14-18-MM-/224135684974

 

[Dieselcamino]

Future reference...

https://www.ebay.com/itm/393214008772?epid=783493154&_trkparms=ispr=1&hash=item5b8d619dc4:gN0AAOSwZ-1gWSo4&amdata=enc:AQAGAAACsPYe5NmHp%2B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSU8qUIAeVPdz29zRlje3Lg9b%2Fyi9xhPZkIkuFXQZj%2FLMDyfvDf8Go9vpdv4mkuNlP3JaWIRnxUzaY7YjEDEVSkc5ky9zC0vp8XqmoDh9WAIeW4I37i%2F66Bip0Dfp3EnW6bNLdmNew3wzLSRTMKbEuySwUbjMSKIug%2BcG0Ky98Z0Rqo%2FkYIfjnFvZmGC0PbH3gzOWwOeUjrt0p0GE1WPfhqhQlIXWOhTomGGxDc53nyugLZFxUUJBvRUwXrZLbPCq89XLct%2FFQOxh1KCVrxepVaoRHuo%2BbyEBb%2FwajXtkCpuGDIYlbA58hXsgU26dnrhCJAjIqIhC7dfz9gWy6aV4Lf%2BWOjQZjWQgeano1xpwqqHnLuKJrz57t8%2BS6J%2FYa4f0IWek1UKc7QA5xe2R9M48RTXOEpRkHztujKLuw05GJu7Ik7PjHp%2BGkxwtJrI4bJE4LgB2TD4tE0nsY%2FASSZLT%2FhNbxIkNg1nFTmCA%2Bmh%2B7OUOyYLl6VxT7e65CuBQ4%2BCvE%2BjuqrDryoImOubQ7mEIcSooI3Ku5DgmF%2F7TkR5lo4vZQ7hQcyAtLPTlQd6%2FhNPgMd1eMyRAEVSCPCpHS1BEmV1UFltrko9SU17TQ6Je7CGNCk5HLS7V86Woy%2BDDgk%2BDxOr1JaqDVolwxuGPFMkWKofnwq7SJVnezjq4yCpzBtX9mfCMEa8hRlmWkwTnyRw6fkHTE%2F7v1XK8yVw3Da8GObSXOU%2FeNGH%2FxU4kjVjQjhVkONnRkbiEr%2FK2RaCTfDLkg8SZ5kmzgFJ0EGbjBDjJfWHaJ1eC7CCN%2BJw%2BRBef8BJpkk%2FL5KaD56nlNKJePA8Brhv3AZW1KgKV4R7%2BvlRPU8japUoZVujh8lUl51Tlez7Q%3D|clp:2334524|tkp:BFBMroGdgPBf

I got this one but see none in stock now. Works very well..

https://www.ebay.com/itm/STRANDIX-1...-ENGINE-SERVICE-3-HOSE-14-18-MM-/224135684974

Thanks I will probably pick one up, I hate cheap tools.

 

[Okie]

Good job: those two links I posted previously have several [pages plus refer to other posts about such and lots of tips from different guys with experience.
Those links I [posted previously) mentions the Strandix and a Actron comp gauges for chainsaws plus mentions how to make your own tester and adapters, how to modify a schrader tire valve into the weaker white valve by cutting the spring, parts numbers for buying the low pressure schrader valves.
I have the Actron which came with several adapters and a carrying case and the low pressure valves (think myabe I got it from Amazon) plus I also built a homemade compression tester so as I could confirm that I was not being lied to by a tester.
When I see a low compression reading on a small ccc engine I confirm such by susing my other gauge.
Also the low pressure schrader valves will need to be cleaned sometimes due to small carbon grit causing them to not back check good.

 

[labans]

Old piston and cylinder

Excellent final result.
Now that we have the disassembled photos I can say that had I had a customer with a cylinder/piston that were scored that badly I would have ONLY recommended replacement with new!!
Good job!!!!

 

[labans]

Future reference...

https://www.ebay.com/itm/393214008772?epid=783493154&_trkparms=ispr=1&hash=item5b8d619dc4:gN0AAOSwZ-1gWSo4&amdata=enc:AQAGAAACsPYe5NmHp%2B2JMhMi7yxGiTJkPrKr5t53CooMSQt2orsSU8qUIAeVPdz29zRlje3Lg9b%2Fyi9xhPZkIkuFXQZj%2FLMDyfvDf8Go9vpdv4mkuNlP3JaWIRnxUzaY7YjEDEVSkc5ky9zC0vp8XqmoDh9WAIeW4I37i%2F66Bip0Dfp3EnW6bNLdmNew3wzLSRTMKbEuySwUbjMSKIug%2BcG0Ky98Z0Rqo%2FkYIfjnFvZmGC0PbH3gzOWwOeUjrt0p0GE1WPfhqhQlIXWOhTomGGxDc53nyugLZFxUUJBvRUwXrZLbPCq89XLct%2FFQOxh1KCVrxepVaoRHuo%2BbyEBb%2FwajXtkCpuGDIYlbA58hXsgU26dnrhCJAjIqIhC7dfz9gWy6aV4Lf%2BWOjQZjWQgeano1xpwqqHnLuKJrz57t8%2BS6J%2FYa4f0IWek1UKc7QA5xe2R9M48RTXOEpRkHztujKLuw05GJu7Ik7PjHp%2BGkxwtJrI4bJE4LgB2TD4tE0nsY%2FASSZLT%2FhNbxIkNg1nFTmCA%2Bmh%2B7OUOyYLl6VxT7e65CuBQ4%2BCvE%2BjuqrDryoImOubQ7mEIcSooI3Ku5DgmF%2F7TkR5lo4vZQ7hQcyAtLPTlQd6%2FhNPgMd1eMyRAEVSCPCpHS1BEmV1UFltrko9SU17TQ6Je7CGNCk5HLS7V86Woy%2BDDgk%2BDxOr1JaqDVolwxuGPFMkWKofnwq7SJVnezjq4yCpzBtX9mfCMEa8hRlmWkwTnyRw6fkHTE%2F7v1XK8yVw3Da8GObSXOU%2FeNGH%2FxU4kjVjQjhVkONnRkbiEr%2FK2RaCTfDLkg8SZ5kmzgFJ0EGbjBDjJfWHaJ1eC7CCN%2BJw%2BRBef8BJpkk%2FL5KaD56nlNKJePA8Brhv3AZW1KgKV4R7%2BvlRPU8japUoZVujh8lUl51Tlez7Q%3D|clp:2334524|tkp:BFBMroGdgPBf

I got this one but see none in stock now. Works very well..

https://www.ebay.com/itm/STRANDIX-1...-ENGINE-SERVICE-3-HOSE-14-18-MM-/224135684974

Thanks for posting some excellent choices for 2 stroke compression gauges! Now if we can just find a supplier with Strandix in stock.....

 

[Dieselcamino]

Excellent final result.
Now that we have the disassembled photos I can say that had I had a customer with a cylinder/piston that were scored that badly I would have ONLY recommended replacement with new!!
Good job!!!!

The pictures make them look worse than they feel, almost nothing to the touch. But for how cheap you can pop in a new upper end why not. It seemed to be the keystone in my journey.

 

[KASH]

Thank God it is fixed.
Kash

 

[Old2stroke]

Good on you for sticking with it and letting us know what the cure was. The more experience you get repairing saws will help when seeking advice on this forum, you will be able to filter out the unlikely stuff and chase down the most probable first.

 

[Automender]

The pictures make them look worse than they feel, almost nothing to the touch. But for how cheap you can pop in a new upper end why not. It seemed to be the keystone in my journey.

Did you use an OEM jug or aftermarket? If aftermarket what brand?

 

[a. palmer jr.]

I would have traded the headaches you've had with the Stihls compared to the ones I've had with the Husqvarnas this year...

 

[Okie]

I would have traded the headaches you've had with the Stihls compared to the ones I've had with the Husqvarnas this year...

Some of them Husky's are not user friendly to work on just so as to gain access to a part to replace or repair. (have to go in the back door first)

 

[a. palmer jr.]

Some of them Husky's are not user friendly to work on just so as to gain access to a part to replace or repair. (have to go in the back door first)

Yep, that was what I was gettin' at..However, the basic problems with Stihls are the same for Huskys, straight gas, too lean mixture, dull chain, poor maintenance. Plus, I don't remember ever working on a chainsaw other than my own that wasn't filthy..

 

[tired]

It's not the type of gauge that matters, it's the location of the Schrader valve and the type of valve that's important. If you don't believe this, try measuring the compression on a 25cc trimmer with an automotive gage using a standard valve located at the gauge and an 8" hose, then do it with a gauge using the special low pressure valve located right at the spark plug hole.

Thanks for this - someone just gave me a Makita DCS 400 that they couldn't get going. First thing I did was check for spark, and it was good. Then used my compression tester (valve at the gauge with a 10" or so hose), and after 5 or 6 pulls all it would top out at was 100. I took the air filter off, put the plug back in and wasn't expecting much, but it fired up straight away and ran like a top. Old fuel mix too - hadn't run in 3 years or so and tank wasn't drained. I was pretty surprised as the reading was so low, but this explains that. Going to take it apart and give it a good cleaning (which it's never had) and wash the air filter. The thing just screams as is, very responsive throttle. Then get to work on the other 14 or so I have. Everything from a Farmsaw with no coil, Oleomac that I haven't looked at, to a few Homelites of various models. Got them all for about $20 each, something to fool with in the winter and learn from. My first post here, and I'm sure I'll be back for free advice. If you know where I can find a coil for the Farmsaw, I'd appreciate a heads up. Things seem to be like hen's teeth.