Walbro WA carb rebuild pix

[wdfccf73]

Great Post!!!!! Send me a PM on how to save this thread to my profile, So I won't have to search for it later on....

Thanks,
Chris

 

[fc2783]

If your talking about the little screen that sits down in the hole and acts like a filter,,IF it was covered by a plug the fuel would go nowhere !!.. sounds like somebody may have thought a welch plug should be there but NO !

make sense
thanks

 

[Dan_IN_MN]

Great thread!!!
This is exactly why I love this forum, a guy goes out of his way to be helpfull, to those of us that don't know!
Thanks!!!

And you think Ron did for you? NO! He did it so he could remember! :biggrin: j/k

Nice write up!

 

[koppertop]

Walbro WA questions

Howdy everyone.

Great forum with loads of good info. I have a question regarding the rebuild of a walbro WA 2C carb off an older stihl 031ave.

My question is about the fuel pump side. In the above photos (great info thanks) it shows the fuel pump next to the carb body, followed by the gasket, then the fuel pump cover. However, in the Walbro WA pdf it seems to show another item between the carb body and the fuel pump cover (number 31) the "diaphragm surge chamber".

http://wem.walbro.com/distributors/servicemanuals/WAseries.pdf

Farther down in the Walbro WA pdf (page 6, re-assembly) it only mentions the fuel pump diaphragm and the pump gasket (no mention of the diaphragm surge chamber)

How do I put this beast back together? When I disassembled the carb there appeared to be three things (pump, gasket, and another gasket type thing) between the carb body and the fuel pump cover.....I have no confidence that whoever re-built the carb last did it correctly and would rather not repeat any mistakes. To slightly complicate things the rebuild kit k10 seems to include lots of things you don't actually need.

Thanks for any tips!

 

[roncoinc]

Howdy everyone.

Great forum with loads of good info. I have a question regarding the rebuild of a walbro WA 2C carb off an older stihl 031ave.

My question is about the fuel pump side. In the above photos (great info thanks) it shows the fuel pump next to the carb body, followed by the gasket, then the fuel pump cover. However, in the Walbro WA pdf it seems to show another item between the carb body and the fuel pump cover (number 31) the "diaphragm surge chamber".

http://wem.walbro.com/distributors/servicemanuals/WAseries.pdf

Farther down in the Walbro WA pdf (page 6, re-assembly) it only mentions the fuel pump diaphragm and the pump gasket (no mention of the diaphragm surge chamber)

How do I put this beast back together? When I disassembled the carb there appeared to be three things (pump, gasket, and another gasket type thing) between the carb body and the fuel pump cover.....I have no confidence that whoever re-built the carb last did it correctly and would rather not repeat any mistakes. To slightly complicate things the rebuild kit k10 seems to include lots of things you don't actually need.

Thanks for any tips!

Yes,,xtra parts for diff applications..
all you need is,carb body,fuel pump,gasket,cover..done.

 

[tbone75]

all questions answered here in what i uploaded,be patient,takes a few seconds to load just click on a folder..



DivShare - Folder - CarbStuff

This will be a great help!Thanks Ron

 

[a. palmer jr.]

Yes,,,,BUT,,check out the second pic and see how to use the straight edge
It's shaped like "W" because it's made by walbro ??
I should get the "Z" shaped one from Zama and make wind chimes ?

I wonder if they have one shaped like a "T".

 

[roncoinc]

I wonder if they have one shaped like a "T".

athat way we could have thre "tones" from the wind chimes ??

 

[koppertop]

Thanks! Part way there...

Ron,
Thanks for the clarification regarding the fuel pump side (carb body, fuel pump, gasket, cover, done). My Walbro WA 2C carb is reassembled and installed. Unfortunately i have encountered another (strange?) problem.

After the carb was installed the saw fired right up. As it was late, i figured i'd leave tuning the carb for another day. Somehow the carb is leaking gas very slowly when the saw is off. I borrowed the "W tool" to set the lever, so i believe that is set properly. I don't believe the carb is leaking from either of the two gaskets. It APPEARS that it may be leaking from inside the carb throat and then slowly dripping out the air filter side of the carb. Any ideas? It is a VERY slow leak but if you watch of the course of a couple minutes a small drop forms on the lower back edge of the carb......like I said it appears that the drip originates from somewhere in the carb throat.

Does this mean that the main needle (unsure of term, the needle that is controlled by the lever that i set with the W tool) isn't seating properly? That main needle is what lets gas into the carb correct? Do i have some built up pressure when the saw is off that is activating that lever and keeping it open? HELP! i'm confused!

Any suggestions. Stihl 031ave if that is important.

thanks again!
KT

 

[a. palmer jr.]

Ron,
Thanks for the clarification regarding the fuel pump side (carb body, fuel pump, gasket, cover, done). My Walbro WA 2C carb is reassembled and installed. Unfortunately i have encountered another (strange?) problem.

After the carb was installed the saw fired right up. As it was late, i figured i'd leave tuning the carb for another day. Somehow the carb is leaking gas very slowly when the saw is off. I borrowed the "W tool" to set the lever, so i believe that is set properly. I don't believe the carb is leaking from either of the two gaskets. It APPEARS that it may be leaking from inside the carb throat and then slowly dripping out the air filter side of the carb. Any ideas? It is a VERY slow leak but if you watch of the course of a couple minutes a small drop forms on the lower back edge of the carb......like I said it appears that the drip originates from somewhere in the carb throat.

Does this mean that the main needle (unsure of term, the needle that is controlled by the lever that i set with the W tool) isn't seating properly? That main needle is what lets gas into the carb correct? Do i have some built up pressure when the saw is off that is activating that lever and keeping it open? HELP! i'm confused!

Any suggestions. Stihl 031ave if that is important.

thanks again!
KT

Did you buy the complete kit or just the gasket kit? If you bought the gasket kit it's possible the plunger might have some roughness not letting it seat very well. It's also possible the spring might be a little weak.
You might check their website for further info. Welcome to walbro.com

 

[watsonr]

The needle is not seating properly, it might be clogged.

 

[roncoinc]

The needle is not seating properly, it might be clogged.

That area would be a place to check..
clean needle tip,clean seat.
make sure vent hole in diapharm cover is clean/open.
usually pushing fuel out of a saw that isnt running is excess pressure in the fuel tank.
loosen cap or check tank vent.
realize the lever setting is only a "close" guesstimate..
proper setting is by "pop off pressure" , and not many do that..
imagine how a new diaphram changes as it ages,when new has a lot of flex and will move a lot,as it ages it dont move so much.
if yours is new try setting the lever a little more down..the new flexable diaphram will move enough to open the needle for more fuel and spring back to shut it off.
still i wouils suspect a dirty needle seat as watson said..

 

[koppertop]

Thanks for the ideas........

Everyone,
Thanks for the ideas. I'll be giving them a shot over the weekend...

As a follow up. Yes it was the complete carb kit so i did install a new needle, lever, and pin. I did spray a the whole rig out with carb cleaner very well several times but will likely repeat when i take the carb off. I have checked and the vent hole in the diaphragm cover is clean/open...

Roncoinc - Very intersting, pressure in the fuel tank??? Prior to attempting to rebuild the carb i cut a little over a cord with the old beast, it ran fairly well but had VERY touchy carb adjustments that seemed to "drift". When i would go to gas up the saw i often got a hissing sound when cracking the gas cap. It was difficult to tell if air was rushing into the tank (partial vacuum in tank) or if air was rushing out of the tank (pressure in the tank). Once, it seemed like a little spritz of fuel shot out of the gas cap/hole right as i cracked it, so it may be pressure in the tank as you said.

How do i fix pressure in the tank? What causes pressure in the tank? I assume pressure in the tank is not wanted? I'll check the vent hole in the fuel cap (i'd be on cloud 9 if clearing the gas cap vent hole fixed it). Anything else?

At least initially the saw seemed to run decent w/ the new carb rebuild. I'm optimistic that if i can get the slow drip fixed it will be GREAT.

Thanks so much for everyone's help and ideas! Internet brainstorming is a great thing!
Cheers!
KT

 

[roncoinc]

Everyone,
Thanks for the ideas. I'll be giving them a shot over the weekend...

As a follow up. Yes it was the complete carb kit so i did install a new needle, lever, and pin. I did spray a the whole rig out with carb cleaner very well several times but will likely repeat when i take the carb off. I have checked and the vent hole in the diaphragm cover is clean/open...

Roncoinc - Very intersting, pressure in the fuel tank??? Prior to attempting to rebuild the carb i cut a little over a cord with the old beast, it ran fairly well but had VERY touchy carb adjustments that seemed to "drift". When i would go to gas up the saw i often got a hissing sound when cracking the gas cap. It was difficult to tell if air was rushing into the tank (partial vacuum in tank) or if air was rushing out of the tank (pressure in the tank). Once, it seemed like a little spritz of fuel shot out of the gas cap/hole right as i cracked it, so it may be pressure in the tank as you said.

How do i fix pressure in the tank? What causes pressure in the tank? I assume pressure in the tank is not wanted? I'll check the vent hole in the fuel cap (i'd be on cloud 9 if clearing the gas cap vent hole fixed it). Anything else?

At least initially the saw seemed to run decent w/ the new carb rebuild. I'm optimistic that if i can get the slow drip fixed it will be GREAT.

Thanks so much for everyone's help and ideas! Internet brainstorming is a great thing!
Cheers!
KT

Everything geting hot and the gas/vapors expanding is all it is.
usually on very warm days or after a lot of use.

 

[sefh3]

Thanks for taking the time to post this. It's great to have visual's. I added it to my signature so hopefully we'll get more use of it.

 

[a. palmer jr.]

I think it would be better to have a small amount of pressure in the fuel tank rather than vacuum. Pressure will allow the fuel to leave the tank, a vacuum would hinder it.

 

[koppertop]

a plan........

Ok, so here is the plan. Let me know what you think.....

After the recent walbro wa 2c rebuild (complete kit) i have had problems with my carb leaking while the saw is off from what looks like the throat of the carb (i.e. it doesn't appear to be a leak at the gas line or a gasket area). Two possible causes have been identified. 1) something causing the needle to not seat properly and/or 2) pressure in my gas tank.

I have noticed in the past that i get some hissing when i open up the gas cap while cutting (possibly pressure?). I took my gas cap and attempted to blow through the cap from the inside toward the outside.....nothing....no air flow....only icky lips.

So, i filled up the saw and set it on my work bench with clean cardboard under it and DID NOT INSTALL THE GAS CAP (don't worry it is outside in a shed). If the carb is leaking because of a poor needle seat it should leak tonight, correct? If my leak was caused by pressure in the gas tank I should have no leak tonight, correct?

Thoughts? Problems with my plan? Should this narrow it down to which of the two possible problems is causing my leak?

Luckily i was recently given a parts saw (031ave). Low and behold when i blow on the gas tank cap from the parts saw i can feel a little air going through the cap (and more icky lips).

With a little luck and the useful info from the guys and gals (any gals in here?) on this site i'll be back up and cutting soon.
Cheers!
KT

 

[dswensen]

Ok, so here is the plan. Let me know what you think.....

I'd just leave the gas cap on but slightly unscrewed so the gas doesn't all evaporate. Otherwise,,, makes sense.

 

[jerrycmorrow]

good timely info ron. thanks much.
i just rebuilt a WT-624 carb. and have the question regarding how to set the metering lever without having the "W" tool. so, just to clarify in my peanut brain. you are saying that the lever end should be even with the raised bosses around the lever end. correct?

 

[roncoinc]

good timely info ron. Thanks much.
I just rebuilt a wt-624 carb. And have the question regarding how to set the metering lever without having the "w" tool. So, just to clarify in my peanut brain. You are saying that the lever end should be even with the raised bosses around the lever end. Correct?

yes.......