Stihl 020 AV Super will start but dies

[StevenW]

I recntly picked up this saw for a good price but found that it had gas in it that had to be 5yrs old.

I have rebuilt the carb. Split the case and cleaned the gas tank, replaced the fuel line and filter and put it back together with a new gasket. I also put a new Autolite plug in. After adding full choke and and part throttle it fired up and ran like a banshee for five minutes then started loosing power (throttle) but I kept it running for 3 or 4 more minutes before dying completely.

I pulled the plug and checked the spark while it was hot and it was still good. I dumped the 87 octane and put 92 octane 50:1 mix, let it cool for a couple hours and started it agian and it did the same thing.

Next thing I replaced the vacuum line to the fuel pump and it does the same thing. I assume it is not getting a steady supply of gas but I cand figure out why.

Any ideas would be greatly appreciated.

 

[volks-man]

I recntly picked up this saw for a good price but found that it had gas in it that had to be 5yrs old.

I have rebuilt the carb. Split the case and cleaned the gas tank, replaced the fuel line and filter and put it back together with a new gasket. I also put a new Autolite plug in. After adding full choke and and part throttle it fired up and ran like a banshee for five minutes then started loosing power (throttle) but I kept it running for 3 or 4 more minutes before dying completely.

I pulled the plug and checked the spark while it was hot and it was still good. I dumped the 87 octane and put 92 octane 50:1 mix, let it cool for a couple hours and started it agian and it did the same thing.

Next thing I replaced the vacuum line to the fuel pump and it does the same thing. I assume it is not getting a steady supply of gas but I cand figure out why.

Any ideas would be greatly appreciated.

when replaceing the fuel line.... use the 2nd fuel pickup line extension too if you can get one. sometimes the saw will run out of fuel even with fuel in the tank... the line/pickup is too short from the factory.

there is a lot going on at the carb adapter flange on that saw. make sure you aren't leaking fuel or vacuum at the flange/intake boot/carb.

know now that even the best mechanic can rebuild an
020av/avs/avp carb and not have it work. the 020av carbs are all junk. every one of them. every time.

 

[StevenW]

Thank you volks-man. What is the "2nd fuel pickup line extension"? The fuel line on mine is inside the tank, which is a two piece tank with a gasket, and has a filter on the end and a rubber grommet that the carb plugs into.

I know the carb boot is good because I have taken it off twice and it looked fine.

I downloaded the Walbro WT manual and I have studied the carb and understand how it works. When I took it apart I soaked it and completely rebuilt it and I'm pretty confident that it is right. And like I said, it runs perfect for about 5 min then it acts like it runs out of gas.

 

[oaky]

No answer? I'm experiencing the same problem on my 020av

 

[rbrown]

Check to see if your fuel cap is venting.

 

[9thpirate@gmail]

So, I also just acquired an 020av with a walbro WA on it, carb is clean and fresh kit. Same issue, starts and then dies. Had it running yesterday for long enough to start fine tuning, then it died and dumped fuel from the carb maybe? Flooded? Idk, gonna pull apart and try again, definitely seems like a finicky thing

 

[SEAM]

Removing the tank housing will kill the fuel line (grommet portion) in virtually all cases on this model...