Dropped Saw

That might do more damage.

maple1 said:

That might do more damage.

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It absolutely will - but he doesn't seem interested in actually fixing the saw, just getting it started.

hi there M1,......i have a Stihl blower that quit running on me once. Been working on motors for long time and can usually figure things out. This one i could not. Took it in for $25 they told me what was wrong. Turns out Stihl uses engineering trick where they join adjacent parts. They machined the keyway from the inside bore on the flywheel which is made out of alum. In order for them to be able to do this they had to under cut the key portion. Keys are normally made from steel but this allowed them to use 1 less part and save on assy costs. Only problem with this is it made things weaker. When the alum key broke it allowed the flywheel to rotate enough to throw the timing off not allowing the spark to hit at the correct time in the stroke. My keyway broke when i shut it down immediatly following use......no impact it just broke. The impact from a 10 ft fall may have caused this condition. Your spark should occur just before the piston is at full up.See if you can check this as it may be your problem. btw i did file a new keyway into the flywheel and installed a steel key. It has been running fine ever since......good luck.......rn

Great story. You had a good tech look at it. Most of them just shrug their shoulders and blame it on misuse.

Vikestand said:

Some people read what they only want to.

I'll fix the cylinder and piston. But I'm not going to drop another 60-70 bucks if other chit is messed up on it. I'm not going to go cut down a 100 year oak with it if it fires. A scarred piston and ring is a cheap after market fix. I can tell if that is the only issue or not after it fires.

I didn't think I had to explain this. Apparently that wasn't the case.

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I read the thread in its entirety. You didn't make it very clear whether or not you were capable of doing repairs yourself - In fact I assumed you couldn't because -
A. You took it to a shop to get checked, and then
B. You took it to your friends to have him do a compression check.
After coming to the conclusion that you would have to pay someone to do the repair, it wouldn't make sense to spend time/money on the small stuff. But with your response I know for sure one thing - You're smarter than anyone else here offering help. Good luck with the saw.

Vikestand said:

Some people read what they only want to.

I'll fix the cylinder and piston. But I'm not going to drop another 60-70 bucks if other chit is messed up on it. I'm not going to go cut down a 100 year oak with it if it fires. A scarred piston and ring is a cheap after market fix. I can tell if that is the only issue or not after it fires.

I didn't think I had to explain this. Apparently that wasn't the case.

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It might not be possible to tell on other damage, until the saw is taken apart. If it doesn't start, that doesn't necessarily mean other things are wrong. It might be just the top end. And if it does start, there might be bits in there that might get into the bottom end and really mess it up - even with just running it a few minutes & not cutting anything. Or the cylinder might get scored beyond just rubbing it out. And if it runs there still might be other issues, like a lean condition from a leaking crank seal that would let it run but cause damage all over again that would take out a new top end. Or a dirty carb. I think you said that you found spark - I don't think you can verify anything else now without a teardown.

Vikestand said:

A full rebuild will be in order when cylinder gets replaced. Any tips on good aftermarket piston/ring and cylinder kits?

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In situations like this, the original cylinder is often reusable. The plating in the bore is so much harder than the melted aluminum that gets stuck to it that it's fairly easy to sand and buff it clean without distorting the cylinder wall. Some people use strong acid to remove the aluminum transfer, avoiding any risk of doing mechanical damage with abrasives, but if there's a nick in the plating then the acid can get under it and eat into the underlying aluminum, ruining the cylinder. If there are chips or deep scratches in the plating then you're out of luck, but more often than not the cylinder can be saved.

The advantage to reusing the cylinder is that OEM cylinders tend to be substantially higher quality than aftermarket. The cheapest, no-name rebuild kits can be truly awful, with very low-quality castings and plating. There are better-quality kits, but the thing you're up against is that you're fixing a saw that was cheap to begin with, so it doesn't make sense to spend a lot on it.

My first choice would be to clean up the original cylinder and use a Meteor piston. If the cylinder were unusable, then my fallback would be this Raisman kit. I doubt I'd spend more than that on a 180.

Because it's a clamshell motor, you'll need a tube of appropriate sealant for where the upper and lower halves of the crankcase assembly seal around the bearings. Some people use the red high-temp Permatex commonly available in every auto parts store, but the instructions will tell you it's not good for seals exposed to gasoline, and I haven't been willing to risk it. There are a number of better sealants actually intended for this sort of use, but they can be hard to find. I use Permatex Motoseal 1, which I was able to get from a well-stocked specialty auto parts store a few miles from home.

BTW, since you say you don't have much experience with 2-cycles it's worth mentioning the importance of proper carburetor adjustment. If the high-speed needle is set too lean then you'll just melt another piston.

Vikestand said:

A full rebuild will be in order when cylinder gets replaced. Any tips on good aftermarket piston/ring and cylinder kits?

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I got a Huztl top end for an 044 (incl. cylinder), off Ebay, over a year ago but I haven't had a chance yet to get that saw together. Price was certainly right, but there are good & bad stories about that stuff on the net, and since mine is is still in a box (and a completely different saw for that matter) can't give any first hand comment on quality.

I have also heard that OEM parts like this have come down in price quite a bit the last year - so I would likely price a top end kit at a local Stihl dealer first.

I would also either line up the stuff you need to do a vac/pressure test - or find someone to do one for you. And do the test after you get the new top end on but before you put everything else back together. If you find a leaky crank seal I think they can be replaced without taking things back apart - but not 100% sure. (Would likely need a flywheel puller). It might also be worthwhile to get a new carb for it - those are cheap on Ebay, maybe also at a dealer now. With a new carb & verified or new crank seals, most of the potential for this to happen again is gone. As long as a new gasket doesn't fail or something like that - which is also a reason to go with OEM gaskets.

Do a vacuum test before you tear into it. That'll let you know if it has a bad seal or intake boot.

Which buchheits did you take it to? The one in perryville, the guys that work back in that department seem fairly descent. I work on my own stuff so i dont have any experience with there service department.

Lost track - did you ever get the compression checked with a guage? Don't think I read an actual number.

Still seems odd how it wouldn't start at all, now starts great, with nothing done that would fix a non-starting issue. I think.

maple1 said:

Still seems odd how it wouldn't start at all, now starts great, with nothing done that would fix a non-starting issue. I think.

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Well, if the pawls wouldn't engage the flywheel, that would cause a non-starting issue...

Well, yes - but not being even able to crank the saw over wasn't even raised until a post on how to replace the rope, which is after a shop advised the top end was shot. Surely if it was simply a starting side/pawl issue, they would have advised on that - or it would have been noticed as a problem before coming to the conclusion in post # 1 that the saw will not start and wanting to check for spark.

maple1 said:

Well, yes - but not being even able to crank the saw over wasn't even raised until a post on how to replace the rope, which is after a shop advised the top end was shot. Surely if it was simply a starting side/pawl issue, they would have advised on that - or it would have been noticed as a problem before coming to the conclusion in post # 1 that the saw will not start and wanting to check for spark.

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Your facetiousness detector could use a slight adjustment.

Maybe so, lol - there are a few things not in sync on Monday mornings...

Vikestand said:

Haha actually yeah. My FIL did I didn't. Nice to see a SEMO person on here. I live in Sainte Genevieve.

Got the saw started this weekend. Ran like a champ. I did have to fix the dog ears that engage the flywheel. There where two issues with it. One the retaining spring was turning and not allowing the dog ears to open up. Two the spring that holds the dog ears in place wasn't locking in place. Pulled the cylinder off and it actually didn't look bad. I'm not sure if there was a burr or what at the exhaust port but it only rubbed on that side. Both issues fixed and on second pull it started.

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I work in ste genevieve but i live in perryville. Small world afterall

Yes it was like a war between us in football. Lol. We take our hogs and beef to get butchered at etzolds too. They are the best