Fresh Rebuild on Stihl 026, Keeps Locking Up

[KyleK]

Hey All,
Completed my first saw rebuild a few weeks ago on an old 026. Put new bearings, all new seals/gaskets, aftermarket jug and piston (reason it needed rebuilt), spark plug, and impulse line.

Well I've been running this saw for maybe 2 hours max since the rebuild with a 20 inch bar (I will probably go down to a 16" or 18" soon), and I've really had to put it in some thick logs to get it to bog down.

Yesterday I was doing some cutting, had to go back inside for something, and about an hour later fired it back up and put it in a 12" log. Halfway through, the saw immediately dies, making a clinking sound. Tried to pull start it but the string wouldnt budge. I thought, crap, it's cold seized. Pulled off the muffler, didn't see any scoring on the piston, but did see some axial scoring on the cylinder wall, and some small metal shavings in the muffler. Took off the brake, put a wrench to the clutch, and it turned right over. The piston still looked good all the way down to the skirt. So I removed the pull starter, inspected, it looked fine, put it back on, and was able to start the motor. I thought, well that's odd, maybe it was thrown off the flywheel when it died.

So I put it back together, got it started up, let it warm up this time, and as soon as I hit the throttle, same "clink" noise and it's acting seized again.

1. I'm using 50:1 fuel mix. It's not old (maybe 2 months)
2. Last week, the first time using it, I thought the clutch went out because it started to smoke and the chain wouldn't turn. When I started it up yesterday, it cut just fine for about 1/2 hour

Does anyone think this could be due to a clutch? I've never heard of a clutch causing this, and I'm not sure if I can think of a way a clutch would even kill the motor.

Any help is greatly appreciated!

 

[Ozhoo]

You likely have lost a circlip and the piston pin is walking around like it's a county fair. Pull the cylinder and go from there.

 

[s sidewall]

Second on that, pull cylinder and see what came apart.

Steve Sidwell, Samsung On5 using Tapatalk

 

[KyleK]

That would make sense now that you say that. The circlips that came with the aftermarket piston were pretty large, and I had one of the old ones I took off. So I ended up using one of the larger circlips. I'll check back in when I get it apart.

 

[alexcagle]

That would make sense now that you say that. The circlips that came with the aftermarket piston were pretty large, and I had one of the old ones I took off. So I ended up using one of the larger circlips. I'll check back in when I get it apart.

*
I try not to use aftermarket clips ever.....
I usually carefully bend the factory ones back out. If you can move them easily, try again.
*

 

[KyleK]

You were exactly right. Unfortunately the circlip was lodged between the piston and cylinder, and the piston is all chewed up. Gonna try to get a refund, but not counting on it.

Alexcagle, yea I thought there was something funny when I got the circlip. It wouldn't fit so I used the OEM clips which were a little loose. I learned my lesson the hard way on this one.

 

[earlthegoat2]

I have confidence in the Meteor circlips but I cant bring myself to use the less expensive ones from Hyway and Farmer Tec.

 

[Westboastfaller]

I had a 262 clutch on a 357 and it did that. Never made a noise though. It worked perfectly cold but would get reallyy hot in about 5 minute of slashing and stall. I would try keep the revs up but eventually it would grab at a high rev and stop it dead.
I thought it was the same size but perhaps it was slightly bigger ID and was generating heat by being a little close to the brake band.
Sure it worked well on the 262.

You are ignoring the fact that it had metal shavings inside. Why?
Doesn't really matter what we guess does it. You will know soon.

OK boys what are the betting odds on wrist pin clip & crank big end?
I think I will throw down 5 large on crank big end if I can get ball park odds of last Thursday.

If not I'll take 15:1 on foreign object.

* Up date
Ah ****... I'm not even good at post betting.

 

[KyleK]

This is the kit I bought:
https://www.amazon.com/gp/aw/d/B00D...1506832552&sr=1&pi=AC_SX236_SY340_FMwebp_QL65

Doesn't say a brand, I'll look into the meteor circlips for the next jug/piston to go on it.

 

[alexcagle]

I'll tell you about a bone-head mistake I made once.
Ok; most clip packs are in a red plastic packet, and stuck in the backside of the piston.
Once, I failed to notice the clip pack and pull it out, because it was in a clear packet.
Needless to say, it ate itself in about 5 seconds......Dope!!!
*
On circlip installation, the best I have found are the Klein brand needle nose pliers.
Yes, they are about $25.00 USD, but worth it.
They are the s#!t , and last for years of daily use.
I've got the expensive Stihl hookless circlip installer tool, and those pliers work better and faster, with less ruined clips.

 

[Ozhoo]

This is the kit I bought:
https://www.amazon.com/gp/aw/d/B00D...1506832552&sr=1&pi=AC_SX236_SY340_FMwebp_QL65

Doesn't say a brand, I'll look into the meteor circlips for the next jug/piston to go on it.

Generic chinukistan cylinder

Those "long eared" circlips are a bad idea. That ear makes them easy to install but it leaves too much unsupported metal. You can imagine at 13,000 rpm that little wire is subjected to fatigue. If you have to use them, cut the ears off. Loads of circlip discussions here on AS.

 

[earlthegoat2]

This is the kit I bought:
https://www.amazon.com/gp/aw/d/B00D...1506832552&sr=1&pi=AC_SX236_SY340_FMwebp_QL65

Doesn't say a brand, I'll look into the meteor circlips for the next jug/piston to go on it.

If you have a Stihl dealer around it would be easier to order the circlips from them. They are real cheap and quite honestly, I don't even know if it is very easy to get Meteor clips without buying a cylinder or piston kit.

@alexcagle - Do you have a part number on those Klein pliers?

 

[Westboastfaller]

There's some journeyman 'tips' for us right there.^^^^

I got to your third word (packs) and I new how that story was going to end. 5 seconds is what it takes, that's right.

A mechanic/builder I've known from when we were kids of 7 & 8 yrs old did that same thing on one of those cheap Chinese 52mm kits for 365/372.
After spending all day cleaning parts and doing a ground up rebuild with porting & MM....Just as he was putting on the piston the neighbor was cutting through the yard and distracts him with conversation.
He also would use OEM.

Needless to say he was pissed about the older neighbor cutting through and distracting him at the most crucial time and of cource the ol'.." what a stupid place to but them in a clear plastic bag...why wouldn't they tape them to the outside".
Followed up with "I knew they were there but I don't use the ****en things". Then back on to the 'neighbor rant'. Lol

I brought it up about a year later.
and he retorted back with...
" It happend again...twice now"!

I could only guess the second time was another mechanicing & texting 'fatality'. Rocky relationshios will do that.

The irony is that's three failures that I know of due to using. OEM clips.

 

[KyleK]

Alright, unfortunately I'm still having an issue. I can see the circlip (the picture looks like a needle bearing, we'll see when I get it off).

I can't get the GD jug off the piston! I tried pulling it out with needle nose pliers, bolting it back to the saw, turned the crank to break it loose, but it still won't come off. Also tried sticking a punch down in there through the spark plug hole, but it hits the cyl wall. Any ideas before I drill a hole in the top of the jug and get shavings all inside my case? I need my saw back!!

 

[KyleK]

Guess it would help if I actually uploaded the pics.

 

[pioneerguy600]

Place wooden blocks on either side of the connecting rod, between the cylinder and the crankcase base just tight enough to allow for a curved pry bar to be inserted, gently pry up the cylinder working from both sides. Two pry bars ,one on the front one rear will get that cylinder off, its likely ruined anyway.