Carb rebuild questions

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OneStaple

OneStaple

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Hey,

I'm rebuilding the carb on a Stihl 026. Walbro WT 22B carb with Walbro rebuild kit.

For one, notice how clogged the fuel filter screen is. Doesn't look like anything gets past. The saw ran better than I'd expect based on this.

Questions:
1. Do I need to remove the valve jet? If so, do I just punch it through? If not, any harm from soaking it in acetone when I clean the carb?
2. Any suggestions on getting the fuel line nipple off? It appears to be a hard plastic, so I don't want to soak it in acetone. I can rotate it with some force, but it just goes around without unscrewing. It seems it be on notches, as it "clicks" from position to position as it goes around. I tried prying it up/off, but didn't want to use too much pressure for fear of breaking it.

Thanks,
Tyler
 

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cscltd

cscltd

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Acetone no- may eat any rubber components and coating on carb body.
the inlet nipple shouldn’t rotate, it may suck air now if you forced it to move, may have to replace carb if you can’t get it to seal
Only replace nozzle if old one giving issues.
 
OneStaple

OneStaple

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Acetone no- may eat any rubber components and coating on carb body.
the inlet nipple shouldn’t rotate, it may suck air now if you forced it to move, may have to replace carb if you can’t get it to seal
Only replace nozzle if old one giving issues.
I would remove all rubber/plastic before using acetone. If that plastic fuel inlet nozzle can't be removed, then I'm not sure what to do about using acetone (assuming I didn't already mess it up). I'll do a pressure test to see if there's a problem. I assume that's adequate. From don't research, there appears to be an all metal replacement.

What about the check valve? Should I worry about removing/replacing it, especially given the gunk in the fuel screen?

Thanks,
Tyler
 
ZeroJunk

ZeroJunk

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Everybody has their own way I'm sure. I just squirt carb cleaner through the high speed needle adjustment hole and if it comes out in the barrel I assume it is clear. Same with the low speed jet.
Carbs that have fixed jets that get the high side stopped up I just throw away.
A sonic cleaner full of carb cleaner might be a good try for those fixed jet carbs, don't know.
Think I would stay away from acetone altogether.
 
SteveSr

SteveSr

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Hey,

I'm rebuilding the carb on a Stihl 026. Walbro WT 22B carb with Walbro rebuild kit.

For one, notice how clogged the fuel filter screen is. Doesn't look like anything gets past. The saw ran better than I'd expect based on this.

This is likely nylon / glass fibers flaking off the inside of the fuel tank or possibly pieces of a disintegrating fuel filter. Flush the tank with fresh gas and replace the fuel pickup then monitor for recurrence.

1. Do I need to remove the valve jet? If so, do I just punch it through? If not, any harm from soaking it in acetone when I clean the carb?
No. I wouldn't soak it in acetone. May ruin a perfectly good check valve.

2. Any suggestions on getting the fuel line nipple off? It appears to be a hard plastic, so I don't want to soak it in acetone. I can rotate it with some force, but it just goes around without unscrewing. It seems it be on notches, as it "clicks" from position to position as it goes around. I tried prying it up/off, but didn't want to use too much pressure for fear of breaking it.
If it is rotating then it is toast. Use pliers to rip off the plastic and vice-grips to remove the remaining brass fitting. Replacement fuel nipples are available from Stihl or Walbro.
 
Len Ellzey

Len Ellzey

stihlmech
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Jarratt, VA
Hey y'all, the only good cleaner for carbs is non-chlorinated brake cleaner. According to instructors at Stihl Class even the Stihl carb cleaner was to strong to use.
 
pioneerguy600

pioneerguy600

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Every 026 that comes through here gets a WT194 installed, I have very good luck rebuilding them and keep several rebuilt and several brand new OEM ones in stock, have tried other WT two screw models but they were designed after the EPA regs got strict, they work ok but the 194 works great.
 
OneStaple

OneStaple

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Every 026 that comes through here gets a WT194 installed, I have very good luck rebuilding them and keep several rebuilt and several brand new OEM ones in stock, have tried other WT two screw models but they were designed after the EPA regs got strict, they work ok but the 194 works great.
Ok, a few votes for going with the WT194. If doing that, do you just go with an aftermarket one (a quick google search shows a complete one on Amazon for $16)? I assume you don't bother with the $100 version from Walbro. Pioneerguy, it sounds like perhaps you pick up used 194s and rebuild them.

The current WT22B carb was working ok and has both H and L screws. I had just wanted to give it a refresh since I was cleaning up the rest of the saw (opened a can of worms, evidently). I'm tempted to leave the check valve alone, replace the fuel elbow, and put the carb back together with the kit that I already have on hand and see if it runs. I have no reason to believe that anything in the carb is gummed up (other than the white stuff that was in the screen). So there isn't really a need to soak the carb at the moment.

Tyler
 
pioneerguy600

pioneerguy600

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Ok, a few votes for going with the WT194. If doing that, do you just go with an aftermarket one (a quick google search shows a complete one on Amazon for $16)? I assume you don't bother with the $100 version from Walbro. Pioneerguy, it sounds like perhaps you pick up used 194s and rebuild them.

The current WT22B carb was working ok and has both H and L screws. I had just wanted to give it a refresh since I was cleaning up the rest of the saw (opened a can of worms, evidently). I'm tempted to leave the check valve alone, replace the fuel elbow, and put the carb back together with the kit that I already have on hand and see if it runs. I have no reason to believe that anything in the carb is gummed up (other than the white stuff that was in the screen). So there isn't really a need to soak the carb at the moment.

Tyler
I use mostly OEM carbs on the re builders, I did use 3 of the AM ones from Huztl on them and they worked fine, the next three I bought wouldn`t tune and ran lean on the top end, each got replaced with an OEM 194 and yes they cost me more than $100 apiece , I don`t sell the saws cheap so the OEM carbs are worthwhile for me.
 
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