Stihl 034 AV woes

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Bizzaro

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Hi to all,
New here. I bought a Stihl 034 AV last year. I saw one up on CL and did some research. It is supposed to be a real solid saw. Everything I read was two thumbs up. So I went to pick it up. (Summer temps70F) it Started right up. Ran pretty well but smoked a bit till it ran for a while. Shut it off. Started it up again. Same show, maybe less smoke. The guy (clearly a scammer now) said he mixed it 20:1. (2nd ignored obvious "somethings up here" smoking was the first) 20:1 Pretty absurd with the new modern 2 stroke oils we have now. 20:1 was like before I was born! I chalked the smoking up to the 20:1 mix. I got around to running it late in the Summer. I mixed it 40:1. Smoked a lot when I would first start it. It did run pretty well mostly, after a little tuning. But if it stalled it would start hard. I have probably only run 4 or 5 tanks of gas through it. Mixing 40:1 Sometimes seems to overheat a bit. I took it out the other day to get going on next seasons wood. It was a cold day, (20F) and stored out in the shed. When I went to the pull cord, it pulled so hard, I could barely turn over the engine. I mean really hard! So is this thing toast and a waste of time, or should I dig into it? Piston sets are cheap enough, but I don't want to waste time on a dead horse either! So you chainsaw wizards please, what are the likely issues/scenarios? Thanks in advance, My biggest fear and suspicion is the case is cracked somewhere and the chain oil is getting into the gas?
Bizzaro
 
Any 0 series are worth rebuilding 034 is a damn good saw, worst case scenario jug piston and crank seals need replaced along with all consumables. First pull the muffler and take pics of piston and cylinder then we can go from there.
 
well 2 strokes smoke but....generally if it takes awhile to "burn the smoke out" could be other issues....Not sure how common it is but you could have some bar oil getting past the case gasket and into the crankcase....if it seeped in over time could account for the hard pull cold....Really good saws. Clutch side crank bearing is stihl only so parts carry the same wicked too expensive stihl price tag....I had a beat up 026 at one time that leaked oil from the case gasket under the muffler..it would soak the muffler with bar oil when the saw sat around and smoked quite a bit till the muffler got real hot...I didn't want to split the case so I just patched it on the outside it worked.

good luck
the can
 
Drain the oil tank and flush it out with mix. Run it awhile without cutting wood. If the smoke clears then the case gasket problem is likely. You can remove the cylinder and peek in there to see. Look to the front of the crankcase to where the common wall is located. Best fix is a case split but quick fix is loosen case bolts and smear with Honda bond etc. and then let sit a little. Tighten up the bolts and then try it. Mike
 
Yes I retuned it for the new ratio, and popped in a new plug. It would cut like a bear with a sharp chain. But if It shut down it was hard to restart. I did bring it inside today, and I can turn it over, but it is not firing. It still turns over hard. It is said to be a high compression saw? But cold, it was impossible! It does still have the old gas etc. as I am just getting started on this "project". Hopefully it is just my ignorance, and the saw just needs a little attention and tweaking. I have never owned a Stihl. Had a couple of great older Jonsereds, 621 and a 49sp. I still have the 49, but it was getting tired and it is nice to have two saws for, hmmm, predicaments ! Oh and the 49 started on the 3rd or 4th pull! I also had a newer piece o $hit yard/weekender husky that I got rid of. This Stihl is its replacement. Not that Husky's are bad saws, this was one of their entry level saws for occasional yard work. I think Mattel makes them for them!
 
I can turn it over, but it is not firing. It still turns over hard.

Sounds like it's over fueling / flooding on cold starts, when it does this pull the plug and post a pic, or just let us know how wet the plug is?...... Can you tell us the make/ brand of the Carb?....As the Tillys do have issues with the module plate.
 
Yes it is aTillotson carb, but the saw is running fine now except for the leaking bar oil at the case split? It smokes from the oil burning off, not combustion. So I will be splitting the cases at some point. Gaskets are on the way. Also, do I use a sealant on the case gasket? I have Permatex Super Black that was recommended for situations where oil and vibrations are present.
 
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