020av carbs all suck. make your own.

[volks-man]

the title says it all.
i have tried and tried to make the factory carbs work on two different 020AVs.

the first had a walbro wt-15. it sucked. it dumped gas no matter what i did to it. had it apart 800 times and tried 700 different variations of metering height, h, and L.

the second had a walbro wa-1. it sucked. the carb has a removable metering plate. you can see every passage in the carb. all clean, all seats good, still dumping gas.... as in running out the muffler. at least 10
dis/re-assemblies on this one with multiple combos of gaskets.

basically you have to do three things:
1: pull the throttle shaft from the original carb and drop it in to a carb with a similar bore and venturi size, in the same family (wt, wa, ect.). be sure to use the new carb's throttle plate.

2: drill a new fuel inlet in the rear of the carb to match the original carb.

3: yank the new carb's fuel inlet nipple and plug the hole. i tap it and thread a fine thread screw in with fuel resistant pipe dope.

i have one more 020av to repair and i will probably just mod another carb and not even fool with trying the original.:bang:

 

[roncoinc]

the title says it all.
i have tried and tried to make the factory carbs work on two different 020AVs.

the first had a walbro wt-15. it sucked. it dumped gas no matter what i did to it. had it apart 800 times and tried 700 different variations of metering height, h, and L.

the second had a walbro wa-1. it sucked. the carb has a removable metering plate. you can see every passage in the carb. all clean, all seats good, still dumping gas.... as in running out the muffler. at least 10
dis/re-assemblies on this one with multiple combos of gaskets.

basically you have to do three things:
1: pull the throttle shaft from the original carb and drop it in to a carb with a similar bore and venturi size, in the same family (wt, wa, ect.). be sure to use the new carb's throttle plate.

2: drill a new fuel inlet in the rear of the carb to match the original carb.

3: yank the new carb's fuel inlet nipple and plug the hole. i tap it and thread a fine thread screw in with fuel resistant pipe dope.

i have one more 020av to repair and i will probably just mod another carb and not even fool with trying the original.:bang:

Wow man,,seems like bad luck..
but all your doing is swapping same kind of carb for same kind of carb ?? Wa for another WA,,WT for another WT ?
also why not just swivel the input nipple for the right direction ?? another piece of line to reach ??
believe ME , i know what it's like to get frustrated with a project !

 

[Jacob J.]

When you start moving the input nipple around, you create an air leak. You essentially ruin the carburetor.

 

[nanuk]

Wow man,,seems like bad luck..
but all your doing is swapping same kind of carb for same kind of carb ?? Wa for another WA,,WT for another WT ?
also why not just swivel the input nipple for the right direction ?? another piece of line to reach ??
believe ME , i know what it's like to get frustrated with a project !

Sounds to me like the problem is not with the nipple... but something inherent with the carb itself.... How would moving a nipple cause a saw stop dumping fuel?

maybe I'm missing something, but sounds like the issue is inside the carb, perhaps a design flaw. There's something happening that is allowing fuel to freeflow.

 

[roncoinc]

When you start moving the input nipple around, you create an air leak. You essentially ruin the carburetor.

OH MAn !! dont tell me that !! LOL !
now 1/3 my saws will burn down !
they are made to swivel,try it..then test per walbro's intructions..they are made the way they are TO swivel,,..
now i have to add i'm not talking about the bent piece of tubing kind,,i'm talking about the kind that has the square fitting..
i dont have a WAT handy to look at,so round tube,no go,square fitting,ok..

 

[Jacob J.]

Yeah the square fitting nipple you can move, but not the plastic elbow kind or the "bent noodle" kind. If you can easily move the plastic elbow kind, it's already on the way out.

 

[tomtrees58]

you just learned that that's why we always had 2 spares in the truck

 

[THALL10326]

the title says it all.
i have tried and tried to make the factory carbs work on two different 020AVs.

the first had a walbro wt-15. it sucked. it dumped gas no matter what i did to it. had it apart 800 times and tried 700 different variations of metering height, h, and L.

the second had a walbro wa-1. it sucked. the carb has a removable metering plate. you can see every passage in the carb. all clean, all seats good, still dumping gas.... as in running out the muffler. at least 10
dis/re-assemblies on this one with multiple combos of gaskets.

basically you have to do three things:
1: pull the throttle shaft from the original carb and drop it in to a carb with a similar bore and venturi size, in the same family (wt, wa, ect.). be sure to use the new carb's throttle plate.

2: drill a new fuel inlet in the rear of the carb to match the original carb.

3: yank the new carb's fuel inlet nipple and plug the hole. i tap it and thread a fine thread screw in with fuel resistant pipe dope.

i have one more 020av to repair and i will probably just mod another carb and not even fool with trying the original.:bang:

4.Buy a carb,LOLOL

 

[volks-man]

you guys all have it wrong.

listen up fellas, jacob especially (i never get to tell you anything you don't already know! )

there is no fuel nipple on the 020av carb!

the 020av takes it's fuel through a hole in the back face of the carb. the part that mounts against the intake boot. the fuel flows through a hole in the intake boot flange from the carb mounting plate that entirely floats on the intake boot. the carb flange in turn has it's own fuel nipple that pushes in to rubber at the fuel tank.

to make a different carb (even of the same series) work you must drill this inlet hole.

pics to follow.

 

[volks-man]

4.Buy a carb,LOLOL

no thanks. i have a whole big-ass box of carbs that are suitable. they only lack the proper linkage and fuel inlet.

 

[THALL10326]

no thanks. i have a whole big-ass box of carbs that are suitable. they only lack the proper linkage and fuel inlet.

Hmmmm thats a good thing. I just ran the number on the old 020 carb, no more from Stihl. How many of those saws do you have?

 

[volks-man]

Hmmmm thats a good thing. I just ran the number on the old 020 carb, no more from Stihl. How many of those saws do you have?

about 5 i think. i have at least 3 times as many possible carbs.



follow the arrows guys.
heres a view of the carb inlet hole, intake boot hole, and flange with nipple. the hole in the carb is what you have to make. oh, and fill in the regular inlet on the replacement carb.

<a href="http://s263.photobucket.com/albums/ii150/volks-man/?action=view&current=PICT2237.jpg" target="_blank"><img src="http://i263.photobucket.com/albums/ii150/volks-man/PICT2237.jpg" border="0" alt="Photobucket"></a>

next the boot assembled.

<a href="http://s263.photobucket.com/albums/ii150/volks-man/?action=view&current=PICT2238.jpg" target="_blank"><img src="http://i263.photobucket.com/albums/ii150/volks-man/PICT2238.jpg" border="0" alt="Photobucket"></a>

now the final pic. see how the whole shebang floats on the intake boot? weird huh? anyway, the fuel comes in the nipple on the flange which in turn sticks in to a grommet on the fuel line mounted on the tank.

<a href="http://s263.photobucket.com/albums/ii150/volks-man/?action=view&current=PICT2240.jpg" target="_blank"><img src="http://i263.photobucket.com/albums/ii150/volks-man/PICT2240.jpg" border="0" alt="Photobucket"></a>

 

[THALL10326]

about 5 i think. i have at least 3 times as many possible carbs.

Welp remember now, just because one of those carbs may work on it doesn't mean its right far as fuel delivery goes. Check your jet sizes so you don't too lean or too fat...

 

[volks-man]

Welp remember now, just because one of those carbs may work on it doesn't mean its right far as fuel delivery goes. Check your jet sizes so you don't too lean or too fat...

bah!
the way i figure it, if the bore and venturi are right then the jetting should be close. besides, if it idles, cuts and four-strokes at wot, no load... good enuff.

 

[THALL10326]

bah!
the way i figure it, if the bore and venturi are right then the jetting should be close. besides, if it idles, cuts and four-strokes at wot, no load... good enuff.

And if it don't????????????

 

[volks-man]

And if it don't????????????

if it don't it won't.
whatsit matter? it's just my saw. it's not like i'm fixing it for hire or something.

first one i did was a walbro 16-b from a 028. runs like a bear, starts good, idles all day long, and four strokes. and that was a much bigger carb, venturi wise.

this one i used a wa-22-77 as i recall.. but don't quote me. i was only looking for the right venturi size. so far so good.... idles great and four strokes at wot/no load. i'll cut with it tomorrow.

 

[tomtrees58]

its good to put a dual fuel pickup in the tank too

 

[THALL10326]

if it don't it won't.
whatsit matter? it's just my saw. it's not like i'm fixing it for hire or something.

first one i did was a walbro 16-b from a 028. runs like a bear, starts good, idles all day long, and four strokes. and that was a much bigger carb, venturi wise.

this one i used a wa-22-77 as i recall.. but don't quote me. i was only looking for the right venturi size. so far so good.... idles great and four strokes at wot/no load. i'll cut with it tomorrow.

Fair enuff. I was looking to see what that jet size is but the IPL doesn't give a size, only a part number. Thats a old jalopy..

 

[teacherman]

you guys all have it wrong.

listen up fellas, jacob especially (i never get to tell you anything you don't already know! )

there is no fuel nipple on the 020av carb!

the 020av takes it's fuel through a hole in the back face of the carb. the part that mounts against the intake boot. the fuel flows through a hole in the intake boot flange from the carb mounting plate that entirely floats on the intake boot. the carb flange in turn has it's own fuel nipple that pushes in to rubber at the fuel tank.

to make a different carb (even of the same series) work you must drill this inlet hole.

pics to follow.

That is like the 056, too.

 

[volks-man]

verdict?

Welp remember now, just because one of those carbs may work on it doesn't mean its right far as fuel delivery goes. Check your jet sizes so you don't too lean or too fat...

i ran the original 020av with homebuilt carb today. the one with the walbro wt-16b 028 carb on it. i made about 2 dozen cuts (cutting machine!!!) with it before it seemed to be running really fast! i thought, 'oh, crap! thall might be on to something'.
i shut 'er down and grabbed the echo and kept cutting.

i decided to give it a try later on and see if it was just my imagination. funny thing... it wouldn't start! 'oh, crap again!' some detective work later and i find out it was just very low on fuel. i filled it up and it was just fine.
i suppose i need the dual line kit as mentined by tomtrees (thanks tom).

the second 020av which i started this thread about is awaiting my new vacuum tester so i can be sure it isn't leaking air (old tester crapped out).
i have not run it in the wood yet as it seems to need a little too much fuel on both H and L. though, this may just be because it is the wrong carb (wa22-77).