Husky 50 / Walbro ??'s

[PowerMax]

I picked up an old Husky 50 for $20 that was straight-gassed. Piston was melted and cylinder badly scored. I installed a new big-bore kit and couldn't get it to run. Discovered that the crankcase was filling with fuel - I took the carb all apart, cleaned it all out and put it back together. Still wouldn't run and the same problem. I swapped the carb/assembly from one of my running 51's and fired up the saw and it ran great. So I ordered a carb kit - re-cleaned and rebuilt the Walbro WA-82A and reinstalled it back onto the 50. Same problem - saw will barely start, bog real bad and stall out and will not re-start. Crank case and muffler get a lot of fuel in them, and the plug is soaked. Any idea's what is happening with the carb? Acts like the needle is hanging open or something. What is the proper adjustment for the metal tab over the spring and hooked to the needle? I tightened it down with the tab even with the carb body. Also, does it matter which direction the hole on the diaphragm cover plate points? Any help would be greatly appreciated. Not sure what I'm missing here.

View attachment 274697

 

[71dart]

According to my walbro gauge the WA metering lever hight should be set about .080" below the edges of the carb body so you may be pumping way too much fuel. And be sure the hole where the needle seats is completely open and clean. I don't think it matters which way the hole on the cap is lined up, as long as it sits on the carb properly.

 

[pioneerguy600]

That`s a common mistake, on that wallbro the metering lever is set by a gauge made especially for them, it is set around .060 lower than the machined top surface of the carb.

I edited this post to correct an error I made in the original submission, after careful measurements I found that the WA carb gauge actually reads .060 below the machined surface of the carb body.

 

[eiklj]

I'm showing p/n 505 31 67-51 for the carb.
$67 approx.

 

[rmh3481]

Its a common mistake to reverse the gasket and diaphragm order on the metering side of the carb, because it is opposite of the pump side. Against the casting the gasket goes down first followed by the diaphragm and then the cover.

Here are some diagrams that may help;
http://www.walbro.com/media/21895/WAseries.pdf

 

[71dart]

That`s a common mistake, on that wallbro the metering lever is set by a gauge made especially for them, it is set around .030 lower than the machined top surface of the carb.

Thanks for setting it straight. Is that on all WA carbs or just this particular one?

 

[pioneerguy600]

Thanks for setting it straight. Is that on all WA carbs or just this particular one?

After checking my shop notes and making my post I actually took 2 of my Walbro carb gauges out and measured them with my Starret Micrometer. The difference between the center prong on the W shaped gauge and the two legs the gauge rests on the machined surface of the carb is actually .060, this is for the WA carbs. I had .030 written into my shop notes for some odd reason but I always use the actual gauge to set the lever with. I don`t want people to get confused or use the wrong setting so I am going to change my former post to read .060 and maybe you can change yours to read the same unless you have measured your gauge and it reads differently. The 2 of my gauges read within .001 of each other.

 

[71dart]

After checking my shop notes and making my post I actually took 2 of my Walbro carb gauges out and measured them with my Starret Micrometer. The difference between the center prong on the W shaped gauge and the two legs the gauge rests on the machined surface of the carb is actually .060, this is for the WA carbs. I had .030 written into my shop notes for some odd reason but I always use the actual gauge to set the lever with. I don`t want people to get confused or use the wrong setting so I am going to change my former post to read .060 and maybe you can change yours to read the same unless you have measured your gauge and it reads differently. The 2 of my gauges read within .001 of each other.

Mine was just a close guess holding a scrap of paper across the W gauge and checking with a mitutoyo caliper. I could easily be .020" off so I bet we can agree. In any event, it sounds like the OP may want to adjust his metering lever.

 

[pioneerguy600]

Mine was just a close guess holding a scrap of paper across the W gauge and checking with a mitutoyo caliper. I could easily be .020" off so I bet we can agree. In any event, it sounds like the OP may want to adjust his metering lever.

Yes, most definitely. If it is set flush with the top machined surface of the carb then it will flood like crazy.

 

[PowerMax]

OK, thanks for the information. I made sure the diaphragm and gaskets are in the correct order, and they were. I may not be sure how to get the tab .080" below the deck height. I pushed the tab clear down with a small philips head screwdriver and tightened up the screw on the rod. The tab springs back a bit after the screw is tightened. I got the tab to remain slightly below the machined body, but only about 0.020". With the play in the slot on the needle, I don't see how it could possibly even pull it open to allow fuel to flow. But, I put it all back together and it would not start and yep, plug is soaked and crank case has fuel in it .... again.

 

[pioneerguy600]

OK, thanks for the information. I made sure the diaphragm and gaskets are in the correct order, and they were. I may not be sure how to get the tab .080" below the deck height. I pushed the tab clear down with a small philips head screwdriver and tightened up the screw on the rod. The tab springs back a bit after the screw is tightened. I got the tab to remain slightly below the machined body, but only about 0.020". With the play in the slot on the needle, I don't see how it could possibly even pull it open to allow fuel to flow. But, I put it all back together and it would not start and yep, plug is soaked and crank case has fuel in it .... again.

You need to bend that metering lever by holding down on one end with a small screwdriver and then pushing down on the opposite end with another, I can actually bend them with my finger. Once set at the proper height the metering diaphragm only needs to press the high end of that lever down .015 to allow fuel to flow. Sometimes the needle valve cannot shut off the flow of fuel if there is gunk under the tapered end of it where it meets the seat, that is why it is so imperative that the metering lever, spring and needle be taken out of the carb and that well to be cleaned thoroughly during a rebuild.

 

[Wagnerwerks]

I can actually bend them with my finger.

You just had to add that to make us all feel like wusses. .


Good info on this thread... Only really posted to subscribe...lol.

 

[PowerMax]

You need to bend that metering lever by holding down on one end with a small screwdriver and then pushing down on the opposite end with another, I can actually bend them with my finger. Once set at the proper height the metering diaphragm only needs to press the high end of that lever down .015 to allow fuel to flow. Sometimes the needle valve cannot shut off the flow of fuel if there is gunk under the tapered end of it where it meets the seat, that is why it is so imperative that the metering lever, spring and needle be taken out of the carb and that well to be cleaned thoroughly during a rebuild.

Thanks, Pioneerguy ... I'm pretty sure I have thoroughly cleaned the carb twice, but I will take it apart again - just to triple-check under the needle again. I will also bend that tab to achieve .080" below the body height. Thanks for all the information - much appreciated. I have 3 of these units, so any info is very helpful to me. I bought my original Husky 51 new back in 1981 and it has been ultra-reliable for me. I heat my home and shop with wood - 2 fireplace inserts in the house and a free-stander in the shop, so I've cut hundreds of cords of wood with it. I've just picked up the 2nd 51 and now this 50 within the last year, when I've apparently become afflicted with this CAD thing. It is nice to have a few extra saws around though. Now, I also have 3 three Husky brush-cutters - only had one for 21 years and just picked up 2 more this past summer.

 

[F.W.P.T]

I've just picked up the 2nd 51 and now this 50 within the last year, when I've apparently become afflicted with this CAD thing. It is nice to have a few extra saws around though. Now, I also have 3 three Husky brush-cutters - only had one for 21 years and just picked up 2 more this past summer.

The good doctor at your nearest Husky dealer can prescribe you something for your CAD!!!!:wink2:

 

[71dart]

Thanks, Pioneerguy ... I'm pretty sure I have thoroughly cleaned the carb twice, but I will take it apart again - just to triple-check under the needle again. I will also bend that tab to achieve .080" below the body height. Thanks for all the information - much appreciated. I have 3 of these units, so any info is very helpful to me. I bought my original Husky 51 new back in 1981 and it has been ultra-reliable for me. I heat my home and shop with wood - 2 fireplace inserts in the house and a free-stander in the shop, so I've cut hundreds of cords of wood with it. I've just picked up the 2nd 51 and now this 50 within the last year, when I've apparently become afflicted with this CAD thing. It is nice to have a few extra saws around though. Now, I also have 3 three Husky brush-cutters - only had one for 21 years and just picked up 2 more this past summer.

I think pioneerguy measured it closer to .060" below the body height. As he also mentioned, we simply use the W shaped walbro gauge (and there's a Z shaped gauge for the Zamas). They're very cheap and just make it a snap to check the lever heights. If you do a search, I'm sure you'll find em. Especially with your CAD problem, in my opinion , they're worth the money.

 

[PowerMax]

The good doctor at your nearest Husky dealer can prescribe you something for your CAD!!!!:wink2:

Pretty sure that's where I became afflicted with it!

 

[PowerMax]

I think pioneerguy measured it closer to .060" below the body height. As he also mentioned, we simply use the W shaped walbro gauge (and there's a Z shaped gauge for the Zamas). They're very cheap and just make it a snap to check the lever heights. If you do a search, I'm sure you'll find em. Especially with your CAD problem, in my opinion , they're worth the money.

Thanks for the advice ... picked up a combo kit tonight:

New Zama Z Walbro w Carburetor Metering Lever Tools | eBay

 

[PowerMax]

OK, I received my W & Z tools yesterday. I set the tab using the W tool and guess what - it's right where I had it set ... level with the carb body 'floor'. I didn't realize that 0.060" below carb body depth was measured from the outer rim of the carb body. I thought it was measured from the floor of the carb body. I haven't had a chance to try and re-fire the saw, but i suspect my flooding issue has not changed. The seat for the needle looks really clean, as well. Hmmmmm .... :confused2:

 

[almondgt]

I have a husky 50 white top. I remember the original carb plagued me. Couldn't do anything to make it right. I replaced it and was :msp_smile: ever after.

 

[pioneerguy600]

Walbro WA carb IPL,there are other pieces in those carbs that can cause flooding, they don`t come with a rebuild kit and are harder to get plus a bit of a pain to replace, number 21 and number 22 can cause a lot of problems with these carbs. Not easy to service and that is why so many repair shops just install new carbs.

http://www.walbro.com/media/21895/WAseries.pdf