034 av idles but wont rev???

[deer slayer]

Hello all, I'am working on an STIHL 034av of a friends. I initialy got it not running at all and in poor condition ( ie dirty, wrong bar & chain, missing bolts) I adjusted the low screw and got it to idle. Pulled muffler & piston looked great, not knowing any history of it off to the store I go. Replaced A/F, F/F, fuel line & rebuilt carb with kit, replaced missing bolts cleaned it up. I had a 20" bar and chain that fit, pulled cord idled fine. Adjusted low screw and went to rev for high adjustment with no luck. Seems to be starving for fuel is my guess, when W.O.T. it bogs out, if I release throttle quick enough goes back to idle if not cuts off, one pull goes to idle fine. I have been playing with the adjustments for hours now with no luck it wont run/tune on the the top end????? Just for the hell of it I have tried a different used spark plug, same results ...Maybe it would help if my post was in the right spot, shows how long its been since I've been on here!

 

[scor440]

Post in chainsaw forum.

 

[deer slayer]

Did just now.. trying to delete this one.. sorry not to computer savy.

 

[ch woodchuck]

Check the tank vent?Let idle,turn on side,loosen gas cap for venting.Might also be a faulty gas cap.Good luck

 

[026 fanatic]

Refusal to rev.

Hello all, I'am working on an STIHL 034av of a friends. I initialy got it not running at all and in poor condition ( ie dirty, wrong bar & chain, missing bolts) I adjusted the low screw and got it to idle. Pulled muffler & piston looked great, not knowing any history of it off to the store I go. Replaced A/F, F/F, fuel line & rebuilt carb with kit, replaced missing bolts cleaned it up. I had a 20" bar and chain that fit, pulled cord idled fine. Adjusted low screw and went to rev for high adjustment with no luck. Seems to be starving for fuel is my guess, when W.O.T. it bogs out, if I release throttle quick enough goes back to idle if not cuts off, one pull goes to idle fine. I have been playing with the adjustments for hours now with no luck it wont run/tune on the the top end????? Just for the hell of it I have tried a different used spark plug, same results ...Maybe it would help if my post was in the right spot, shows how long its been since I've been on here!

Check the impulse line. After that, if there is no reaction to setting the carb, there is still probably some restriction. Also, check the fuel line for cracks, the part # for that is 1125 358 7705

 

[Tobystihl]

Sounds like the impulse line. It happened to my 034 a few weeks back, the impulse line had popped of at the cylinder.

 

[Stihlofadeal64]

Take the carb off and look inside. It could be that the screen is plugged up with sawdust. Buy the kit and go through the carb. Disassemble, clean, reassemble with all the new stuff. Make sure you check to see where the metering lever is set before you totally disassemble it. (If you don't have any carb tools you can reset it the same level as the old lever - to start). This may very well solve your problem.

 

[Bashmaki]

It's air . . . .somewhere; gas line in tank or impulse line. God forbid it be one of the crank seals! I hate when that happens; but the reality is it is an old saw. I've got one of those and I don't even remember when I bought it I've had it so long.
Every time I pick it up I expect it to suck air and it never does
I love that little saw!!!

Gus