Stihl 026 headache

[Vintage Engine Repairs]

I disagree, this isn’t a great thread, it’s getting ridiculous. What is going on here? Start another post if you want to know about gauges. Or save yourself the time and accept that a small engine compression tester has some differences, mainly the necessity of a shrader valve in the spark plug adapter.

OP, get the cylinder head off and start measuring and inspecting. Check ring end gap and while you’re there it doesn’t hurt to check skirt to wall clearance.

115 psi compression is too low to reliably run and confirming the measurements will backup your compression test gauge. Upload some pictures too, the intake and exhaust skirt as well as the cylinder bore.

Skirt gap : replace it above 0.13mm
End gap : replace it above 0.01mm per mm of bore

Pioneerguy is spot on with his posts, a dose or reality is needed to get things moving. Don’t throw parts at something if you haven’t bothered inspecting it. You’re just wasting money. Send it to a mechanic it will be cheaper and quicker. Throwing parts at it isn’t teaching you anything.

People need to stop throwing “i’m a mechanic tho” into threads when they are clearly not competent at small engine repair. Anyone who has a clue can see they are talking out of their behinds.

 

[KASH]

My Snapon compression gauge has the mini leak at the valve it is a pain in the a.. on chain saws.
Kash

 

[Captain Bruce]

This thread, and the owner of that POS old 026, valued at $150 on ebay, are priceless humour. Everything seems to be coming out of a Russian reporters mouth................Take the saw to a shop, or the dumpster. get a life and a tax refund check....and go buy a used 250. Boring the members of this site, won't help your problem. Go away.......

 

[Dieselcamino]

This is a great thread.
Please dont part out the saw.
Maybe send it to someone for a different opinion.
We all think different.
Or sell it as is.
I would really like to see it running and what was found.

After this much, I'm waiting on a new cylinder and piston, I'm thinking my compression was on the cusp of being too low, or possible intermittent compression issues from a ring hanging up

 

[Dieselcamino]

This thread, and the owner of that POS old 026, valued at $150 on ebay, are priceless humour. Everything seems to be coming out of a Russian reporters mouth................Take the saw to a shop, or the dumpster. get a life and a tax refund check....and go buy a used 250. Boring the members of this site, won't help your problem. Go away.......

Your correct the saw has minimal value, The last thing I actually need is another saw in my garage, this project is to get a nonrunning saw running again (I wouldn't of come here if it was easy). No members are forced to waste their time on my project (some are actually interested in it as well) to those annoyed by it much like yourself I kindly invite you to "Go away....."

 

[Oletrapper]

Interesting, didn't know there would be a special chainsaw compression tester, I assumed PSI would be PSI

In my experience, psi is not psi depending on the application. Example is a tire gauge. They make one for car tires and one for truck tires. I can't use the car gauge on the truck as it won't read high enough (80psi) and often will brake it. I can't use the truck gauge on the car because it is designed for higher psi readings and will give an inaccurate reading at lower psi tires.
jmho OT

 

[labans]

In my experience, psi is not psi depending on the application. Example is a tire gauge. They make one for car tires and one for truck tires. I can't use the car gauge on the truck as it won't read high enough (80psi) and often will brake it. I can't use the truck gauge on the car because it is designed for higher psi readings and will give an inaccurate reading at lower psi tires.
jmho OT

Here we are 7 pages into this thread with lots of ideas for the OP because folks come here for interest, fun and knowledge.
But I still have to NOTE---not one poster so far has provided us with the NAME BRAND and MODEL of any one of these elusive 2 stroke compression gauges!!

 

[bigbadbob]

I bought a xl250 off a guy that had no spark,, went thru multiple peeps and a shop trying fix it,, they had replaced all the electrical stuff to do with the ignition. Still no spark.
They also kept putting the same ground back on the cdi box.

 

[Old2stroke]

Here we are 7 pages into this thread with lots of ideas for the OP because folks come here for interest, fun and knowledge.
But I still have to NOTE---not one poster so far has provided us with the NAME BRAND and MODEL of any one of these elusive 2 stroke compression gauges!!

What we are trying to point out is THE IS NO SUCH THING AS A SPECIAL 2-STROKE GAUGE. It's just the type of valve and the location of it that makes it special for small 2-stroke engines.

 

[labans]

What we are trying to point out is THE IS NO SUCH THING AS A SPECIAL 2-STROKE GAUGE. It's just the type of valve and the location of it that makes it special for small 2-stroke engines.

Ahhhhh Finally clarified. Please note that in many of the posts there was mention of a "special 2 stroke gauge." Which is why the ask.
Now we know that your particular concern is ONLY the location/type of schrader valve.
So the next question to help us along is: Can you please identify the "type of valve" so that we can find and use the same one? We know the location so that is no longer an issue.
And is it possible for you to post a photo of what gauge you are actually using to help us get a better idea?
Thanks in advance......

 

[Vintage Engine Repairs]

What we are trying to point out is THE IS NO SUCH THING AS A SPECIAL 2-STROKE GAUGE. It's just the type of valve and the location of it that makes it special for small 2-stroke engines.

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

 

[PV Hiker]

Try searching for valve color white. The spring is weaker.

You can read through this 4 page post.
https://www.arboristsite.com/threads/will-the-real-compression-test-please-stand-up.317498/
Or this one
https://www.arboristsite.com/threads/a-compression-check-question-s.344316/#post-7336922

 

[pioneerguy600]

Milton 1251-2 Compression Tester Replacement Valve Core

https://m.media-amazon.com/images/I/61hNDn2ufvL._AC_SL1500_.jpg

 

[PV Hiker]

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

 

[PV Hiker]

That valve is huge! Poked my eye out opening it up!

https://m.media-amazon.com/images/I/61hNDn2ufvL._AC_SL1500_.jpg

 

[Automender]

Here is my compression gauge. Not a brand name but look at the pictures. In the sparkplug adapter is a special poppet valve. It is also an extremely small hole so it doesn't add any volume to the squish area. I reduced the hose to decrease the pump up time. That tiny check valve really doesn't have a strong spring but that doesn't matter too much. Also have one that I got 45 years ago that is for cars that doesn't have that adapter valve set up.

 

[Automender]

My auto compression gauge doesn't have a valve at the adapter but a valve at the quick disconnect. Also the hole is two to tree times the diameter of the small engine gauge. That means I would add the volume of that eight inch hose to the small squish volume of a small 2 cycle.

 

[stihltech]

My auto compression gauge doesn't have a valve at the adapter but a valve at the quick disconnect. Also the hole is two to tree times the diameter of the smallView attachment 971813View attachment 971814View attachment 971815 engine gauge. That means I would add the volume of that eight inch hose to the small squish volume of a small 2 cycle.

 

[stihltech]

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?

 

[Automender]

Agree on the compression, I had a Husky K970 cutoff saw that had worn rings and leaking base gasket and at 75 psi compression the saw started and ran but would not idle and flooded easy. Always wondered were the blowby gases ended up, in the exhaust or crankcase. Ts400 cutoff saw had 120 psi compression and runs great. It is relative. I think people are waiting for the OP to report on cylinder condition since he had ordered a OEM cylinder and piston.