walbro carburetor needle diaphragm adjustment

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1hander

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hey guys, the service manual says to set the needle actuator arm thingy... so that it is level with the top of the body of the carburetor..

the rebuild kit i got which is supposed to be the right one, i had to file down the button under diaphragm, the little metal post was way too long and would have been holding the needle open full time.

so i filed it down so that with the needle actuator even with the top of the carb body, the diaphragm could sit on top of the actuator arm making contact but without pushing on it.

ive never had to file the diaphragm button down like that... does this sound right
 
Sorry but that guys.. Yes 015l
Because of the length of the button if I tried to just bend the arm... The diaphragm button still had so much length that it was holding the needle open permanently.... I could not find a genuine walbro rebuild set
 
Ive got hdc 17b.. And yes it looks like someone has bent the crap out of this control lever.. I think i got it mostly straightened back out.. Well see when I get it put back together if it won't run I know it's the control lever not quite right...

Do you guys set the actuator just parallel with top of carb body( which puts it below the top of the carb body) or with the tip of the actuator up even with the top edge of carb body..

The actuator is just so tweeked outta shape

I just noticed that what I paid for and what came was not a walbro kit.. Out it goes I just ordered a walbro kit..

Even the inlet needle was too long.. So it's not for this carb.. I'll do it over.

I ordered a check valve kit also in case this one goes bad
 
The inlet control lever has to be flush with the carb body. If you place a straight-edge over the carb body the inlet control lever should just touch it, (on the place where the nipple of the diaphragm tips on the control lever) without opening the inlet needle.
 
actually the metering needle was also too long compared to the original...so i used the original

as far as the check valve usually theres an aluminum freeze plug on the opposite side so you can get the check valve out from the opposite side but this carb has no such opening..

service manual says to use a screwdriver to lift the check valve out.. its not torn and was working so i think ill leave it be.. but in the past when the check valve was no good, i would use an old piece of the check valves from the opposite side of the carb and cut a small round circle about the size of the original check valve piece and carefully put it down in the hole ..
sometimes i would have to trim the makeshift checkvalve a bit , but it always worked

after filing down the diaphragm button on the underside and adjusting the actuator, with the old needle, it holds vacuum great.. loses just a bit of vacuum over a 3 minute period but its more than good enough seal.

i ordered a walbro kit anyway to have on hand..
 
Some links to download and view Walbro Diaphragm carb Service data. This one has good info about the HDC carbs.
Some very good info about pressure testing, replacing check valves, etc.

Has info about HDC and WB carbs

A very good link to download Walbro small engine carb service manual for Walbro diaphragm carbs such as HDC, etc. Has how to pressure test and about check valves, etc.

At this link notice the Walbro Manual and info to select the free download manuals.
https://www.eccarburetors.com/Walbro-service-manual


Diaphragm carbs Service data download link

https://www.eccarburetors.com/assets/images/WalbroDiaphragmCarbSM.pdf


Walbro WB service manual data download link

https://www.eccarburetors.com/assets/images/WB-Manual.pdf
 
Thanks man... I love knowledge... All I can get... Man I'm outside it's cold as hell and I'm soakin wet tryi g to get all the 08s and 051 pieces stripped and ready for primer... Man I wish they made paint stripper like they used to.. The stuff they sell is now is garbage
 

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