Carb Kits???

[Trigger Man]

I always woundered with walbro carb kits why they give 2 fuel pump diaphrams in the kit, one is made of material just like the metering diaphram and the other is usually a woven type material or a plastic can anyone explain?

 

[roncoinc]

Trigger Man Carb Kits???

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I always woundered with walbro carb kits why they give 2 fuel pump diaphrams in the kit, one is made of material just like the metering diaphram and the other is usually a woven type material or a plastic can anyone explain

never seen that...
i got two new kits today,only one diaphram in mine.
if you order a kit that may fit more than one carb,like example,WAT will fit WA carbs and WT carbs,thus WAT,you may find xtra stuff but i have never seen more than one diaphram..
post a picture of both.

 

[Trigger Man]

It is actually a walbro wt 501 carb of off a weedeater blower, the kit is a K20-WAT it does only come with one metering diaphram, but comes with 2 fuel pump diaphrams one is made of the same material as the metering diaphram and the other is a white woven type of material or at least that is the best way I can describe it, I have seen other kits come with a plastic mylar type fuel pump as well. I would like to post pics to show you what I'm talking about but I 'll have to get some to show me how to get the pics of of my camera I'm not the swiftest at downloading pics to the computer,sorry.

 

[roncoinc]

It is actually a walbro wt 501 carb of off a weedeater blower, the kit is a K20-WAT

Ok, like i said,the carb kit wil fit either WT carbs or WA carbs,thats why the WAT designation...so you will have extra parts after you do YOUR carb,,they will fit the WA carb..SOME parts are comon to both..use the parts that look like the ones you take out..if you havent rebuilt a carb before keep track of how what goes where !! if you find a little cupped screen in there compressed air WILL blow it out !!.. if you pull out the fuel shutoff needle you WILL lose the spring !! i have no idea what you know about carbs so indulge me please.. i was told many years ago when i did my first one to take it apart in a big plastic bag,glad i did..then i graduated to a big box... easier to find the parts than fly or fall out.. now i just grab a junk carb to replace the parts i lose..wanna know how i got the junk carbs ?? LOL !!!

 

[Trigger Man]

I have rebuilt a fare amount of carbs with very good results, I was just woundering why the two types of fuel pumps in the kits, I do just as you do replace with what came out of the old one, and I'm well familiar with the little fulcrum spring, try finding it on the kitchen floor when the dog thinks you want to play,lol. I guess it just bugs me why they provide two types of fuel pumps that are identical except for what material they are made of thats all .I just wounderd if one pumps better than the other? When i get the camera thing figured out probably tommorrow I'll have some pics to help with my description.

 

[heimannm]

Many carburetors use that white/fiber reinforced diaphragm as a back up to the soft rubber one.

One is described as "diaphragm, fuel pump" and the other "diaphragm, check valve" in the SDC service manual.

Mark

 

[ZeroJunk]

The kits have a blue semi clear plastic diaphram and a black more neoprene looking diaphram with the same design.

Like you, I replace it with what was in it.

I suppose if they were interchangeable they wouldn't put both in there. But, maybe they are.

I rebuilt a Walbro off an 028 this week that had the blue one in it. I'm sure it didn't come that way.

 

[roncoinc]

I just made a post " sun morn reading or ID this saw "
some REALLY good walbro stuff in it and link to repair manual..
explains the carbs very well.

 

[roncoinc]

Yestday i had to do two walbo carbs..
the WJ carb kit did not come with a black soft fuel pump. only the white plastic one so i thought that answers questions about interchanging..
they are NOT interchangeable..i thot at first carb was working so much better is why i needed to change adjustments so far..when saw died i had time to think and see that there sould be NO reason for that..pulled the carb,flooded with gas,plug was soaked and replaced fuel pump with old soft black one ( carb only needed old dried metering diaphram replaced anyway ).
set H/L to 1 1/4 and saw went well..finished adjusting carb and put it away..

second was a WT,( wat kit ) ,this kit also did not have a black soft fuel pump but one of the BLUE plastic ones..thot i may be getting into more problems using it but i did anyway and it worked fine !!

so looks like black soft and blue plastic interchange and the white plastic dont..

 

[lawnmowertech37]

It is actually a walbro wt 501 carb of off a weedeater blower, the kit is a K20-WAT it does only come with one metering diaphram, but comes with 2 fuel pump diaphrams one is made of the same material as the metering diaphram and the other is a white woven type of material or at least that is the best way I can describe it, I have seen other kits come with a plastic mylar type fuel pump as well. I would like to post pics to show you what I'm talking about but I 'll have to get some to show me how to get the pics of of my camera I'm not the swiftest at downloading pics to the computer,sorry.

trigger man the best way i can say this is the k20wat kit fits many different series of carbs so that is why they have extra parts in the kits cause of that very reason

 

[Arrowhead]

try finding it on the kitchen floor when the dog thinks you want to play,:

Been there, done that, then the dog kicks it under the fridge!

 

[Trigger Man]

Sorry Roncoinc, I did'nt get the picture thing worked out yet. However I picked up a K20-WAT kit from my local dealer, and compared it to the gaskets and diaphragm in the WT-501 carb that I'm going to rebuild, you were right the fuel pump diaphragm that fits this particular carb does'nt use the black neoprene, it uses the white woven type. However the carb originally used a blue plastic style fuel pump but the white woven type is the one that matches the blue plastic in terms of lining up with the holes in the carb, wierd? no blue plastic came in the kit.

 

[Trigger Man]

Yestday i had to do two walbo carbs..
the WJ carb kit did not come with a black soft fuel pump. only the white plastic one so i thought that answers questions about interchanging..
they are NOT interchangeable..i thot at first carb was working so much better is why i needed to change adjustments so far..when saw died i had time to think and see that there sould be NO reason for that..pulled the carb,flooded with gas,plug was soaked and replaced fuel pump with old soft black one ( carb only needed old dried metering diaphram replaced anyway ).
set H/L to 1 1/4 and saw went well..finished adjusting carb and put it away..

second was a WT,( wat kit ) ,this kit also did not have a black soft fuel pump but one of the BLUE plastic ones..thot i may be getting into more problems using it but i did anyway and it worked fine !!

so looks like black soft and blue plastic interchange and the white plastic dont..

Roncoinc, you say you just bought a K20-WAT carb kit but did'nt get the black neoprene fuel pump in the kit? I just bought one and it was in the bag with everything else, are you buying genuine Walbro kits or aftermarket kits?

 

[Trigger Man]

Does anyone know the reason behind the three types of material that the fuel pump diaphragm can be made from , does one pump faster than the other or is it because of ethanol in the fuels etc.? I've googled it and can't find an answer.

 

[roncoinc]

Roncoinc, you say you just bought a K20-WAT carb kit but did'nt get the black neoprene fuel pump in the kit? I just bought one and it was in the bag with everything else, are you buying genuine Walbro kits or aftermarket kits

Opps,,i got the K10 kits,,wonder whats the diff there !!!
genuine walbro
i think the diff in fuel pumps may be in application..
noticed a string trimmer i have apart uses a WT carb,i get a chance will pull it apart and look at it.
AFTER i research the dif between the K10 kits and the K20 kits

 

[Stihlhead fishing]

This picture should answer any questions about the pump diaphragms for any brand of carburetor.

 

[Tom Erwin]

thanks for that picture...that answers everything!!!

 

[Popcrop]

Many thanks to the other side of the Atlantic ocean! Your answer was not easy to find for a RC-Modeler. I'll replace the worn out rubber diaphragm by the teflon sparepart (K20-WAT Kit). But what about the pump capability? Does the stiffer teflon really pump more fuel?

 

[nenicu]

Hello from Romania! If you read on the right side of the pictures you will see that the teflon diafragm has better pumping action than acetate or rubberized that are stiffer to start with and in time the fuel makes them stiffer. Today i worked on a 6 years old chinese chainsaw. The teflon diafragm looks and feels new[ the fuel we get here is very low quality compared to yours]. A few days ago i changed a 2 year old acetate diafragm from a Husqvarna 137. That one was stiff and was'nt pumping good[hard start].

 

[diesel&coffee]

Old thread .. just thought to note Romania is right. I post again trmw. Black rubber pumps must fuel but is best for gas. The other two pump less but used in / with methanol etc. I find my ref trmw. The one noted as middle of the 3 is stiffer pumps less but will last a lot longer in methanol .. the last of the 3 is stiffist and pumps the least