Stihl 034 AV woes continued ( in chainsaw threads)

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Bizzaro

ArboristSite Lurker
Joined
Mar 23, 2020
Messages
31
Reaction score
15
Location
Vermont
Here is a video, and more pix. Or not. Vid will upload, but won't play. I am sure it is my technical ignorance.
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
smokes "a lot" ,,This was started in the firewood forum.
 

Attachments

  • 25C7FF55-D832-40BA-B610-C093D31F744D.jpeg
    25C7FF55-D832-40BA-B610-C093D31F744D.jpeg
    1.3 MB · Views: 35
  • FEED0EA0-2BDB-4F95-93F5-7A6EA671CB11.jpeg
    FEED0EA0-2BDB-4F95-93F5-7A6EA671CB11.jpeg
    1.2 MB · Views: 37
  • 48C0FFC4-28BA-46C2-8F85-58316F9FFE3E.jpeg
    48C0FFC4-28BA-46C2-8F85-58316F9FFE3E.jpeg
    1.6 MB · Views: 37
Dont get what your question is exactly.

“Smokes a lot” could be anything.

Take more pics, including with top cover off and the piston through the exhaust port. Saw looks pieced together in some ways. That’s an 034 Super muffler and i don’t believe the composite handle came on 034’s, but I could be wrong.

A pressure test on the saw with the saw laying on its PTO side and some light oil filled to the top in the oil tank should reveal air bubbles coming out into the oil in the tank If the case gasket is bad and causing the saw to suck in tank oil.
 
Just couple hints about your saw:
I've got a 034 that a auto mechanic had tossed in his metal trash dump. He said it had low compression. I asked if I could have it for parts. (had a new chain on it) It was really nasty looking, oil all over it and dirt/dust on top of the oil. Before cleaning it up I pulled the muffler and looked at piston, then did compression test. All checked great. Installed gas and saw would briefly start after priming. Long story short the pulse line behind the carb was cracked. One of my favorite go to saws. Even after cleaning the case it looks sad but is a diamond in the rough. Mine does not pull over as easily as some stihls when it hits the compression crank through on the rope. I ease it up to the hard compression spot then pull thru. Yours might have bar oil in the cylinder which is increasing the compression pull through.
I'm not real familiar with that oil/gas tank configuration. If you suspect it's bar oil getting into the engine, clean out the oil tank and leave it empty, remove the bar and chain and start the saw and see if it still smokes. I've seen some saws do such and not smoke when the bar oil is removed.
You can then rig a pressure test or just take it apart and fix the cross leak. Fill the oil tank with light oil and look for bubbles in the tank while it has not over 5 psi applied.
 
I have a great video of the extreme smoking, it uploads, but won't play. Any help on playing this? Also it seems the exhaust heat shield is missing. When I pulled the exhaust, there was only one fiber gasket. I picked up a new exhaust gasket. It is metal, and ridged in the middle. The guy never mentioned "which" exhaust gasket.
 
I have a great video of the extreme smoking, it uploads, but won't play. Any help on playing this? Also it seems the exhaust heat shield is missing. When I pulled the exhaust, there was only one fiber gasket. I picked up a new exhaust gasket. It is metal, and ridged in the middle. The guy never mentioned "which" exhaust gasket.
So what is the difference between to super and standard. I am starting to think I may have a Super with a standard cover? Looking on line through parts schematic, it is the super exhaust. What is the tell tale difference between the two saws?
The air filters are the same, and nothing pops out to me in my searches other than the exhaust. I know the super is more powerful, right?image.jpgimage.jpgimage.jpgimage.jpg
 
I wiped this dry last night. It is wet again this morning. I think someone did a really sloppy job of replacing the Oiler case gasket and it is "wicking" or leaking oil from the oil reservoir? And what should the compression be? And like a four stroke, do I hold the throttle open when testing the compression? image.jpg
 
034 Super is basically a different sticker on an 036. Some minor differences. An 034 Super AV has been my wood-gitter for a decade. Fantastic saw.

For a video, you might have better luck uploading to YouTube and posting the link here.

Looking forward to hearing what your issue turns out to be and getting it solved.
 
So how do I figure out which saw I have? 034, 034 Super, or mongrel? There has got to be obvious indications for you saw wizards? I am kinda hoping it is the Super with a 034 cover?? How do I tell visually. The parts schem.'s I have seen, nothing jumps out at me except the muffler as Bad Cad alluded to, and I confirmed. Got to be other tell tale signs on the jug or case?
 
46mm = 034. If you take a pic of the cylinder from the top we can confirm... usually.

034= good saw, upgrade to 036 isn’t always needed.

Case gaskets are known to fail there for high-use 1125s. I can’t say for sure if yours is leaking from pics but it’s possible. They don’t have the 1128 heat tape there from factory. I add it to my rebuilds.

Not all 1125s had heat shields between the cylinder and muffler. I add them to rebuilds, though (usually with a 48mm top end).
 
No need to pin the throttle during compression checks. Compression isn’t everything, but stock 1125s are usually 140-160ish for me depending on wear. High hour can be lower, lots of variables.

If it’s heavy smoke and clears with the oil tank empty, a case split is needed. The green aftermarket gaskets are good for this series. The black farmertec are marginal and I would only use a fresh one with Hondabond if I had to. We’ll cross that bridge later, though.
 
It's an 034 AV. Piston is 46 mm not 48. Not sure why it has that muffler. But seen the same exhaust on other 034 AV on YouTube that are not Supers. And no heat shield. It is a West German saw? That's good. And now the bad news. Cases are leaking. Need to split and replace gasket. As long as the compression is good. Like 150 plus? Since this is a complete tear down, what else should I do/replace /check while I am in there? Is this saw worth it? What is this Honda stuff. A sealant? Ultra Black is supposed to be a good sealer for oil and vibration applications? Thanks to all that dropped in. Appreciate the input. I will probably need to improvise some kind of case splitter. All new to me. If ya got some improvised methods, I am listening.
 
It can be daunting for a first timer but really it is not that difficult, depends on what you have to work with and experience level. My first case split I only had heat and a wooden mallet, with more tools now than anyone really needs its a couple hours start to running saw.
 
I am sure I can get it apart! It is putting back together that worries me!
Compression Cold- Solid 150 psi after 8-10 pulls. No need to upgrade to the Super(036 [48mm piston and cylinder])?
 
No need to upgrade, just most on here always want to get the upmost power from any given chassis design. The reg 034 will be adequate for a mid sized saw. I prefer the 036,360, 361 and 362 , its what I have built and kept. I had a 034 it was a good saw but let a friend have it as I have far too many saws for my own use but I try. I build saws just because I like to now, quit working for dealers but find satisfaction in building them for my own use. The oil issue should be corrected as it makes starting the saw much more difficult as time goes on.
 
I still occasionally use my 034AV that I upgraded to an 036. It gives my MS 361 some relief. But, when I want a reliable powerhouse 60cc saw, I go get the 361 and it delivers every time. The 361 was ahead of its time the day it was released -- about 14 years ago. My, how time does fly. Gasp!
 
I can upgrade to the Super, (036) anytime. I won't have to split the cases for that. This saw runs great. I cleaned up the oil under the muffler and used some metal tape to divert most of the leaking. Tuned it up and I am cutting up a large ash that I dropped a couple days ago. It runs fine and the smoking(burning oil from the leak) has stopped! It smokes like a normal two stroke. And it has plenty o balls for me. This thing just rips through wood with ease. Then the muffler screws fell out! So I got some screws and Locktite and put it back together. It will be back in action tomorrow. And I will order the gaskets for the repair. I would like to get my wood for next Winter felled at least before things leaf out up here. This is my first Stihl saw. Probably not my last. I am impressed. Great saw even when it is ill! Kinda reminds me of my 1994 BMW K1100LT. It has NEVER left me stranded. Even when it hasn't been well, it always got me home! I bought an 89 sportster 880 a few years back. I think something went wrong with it every time I took it out, until finally the magneto exploded. A common occurrence on this model. But I digress. Thanks again to all that piped in.
Bizz
 
If you are going through the trouble of splitting the cases to replace the case seal, I would suggest going ahead and replacing bearings and crank seals while you are in there. Then through on new rubber to and from the carb. Those parts are cheap compared to the time spent breaking it all down and putting it back together, or having to put on a new top end because something else fails that would've been 'cheap' and 'easy' to replace while you're in there. Don't be fooled by the price of some of the aftermarket top ends if that is swaying your decision... you get what you pay for and it will never hold a candle to the original that is on it now...
 
Back
Top