Any Idea How to Clean this Jet on Walbro LM series Carburetors?

[rebeltaz]

I have had three of this body style carburetor come through with this passage clogged

I have found that there is a small jet internally behind this ball seal

Getting to it was a destructive [process. Is there anyone who knows how to get to this jet to clean it NON destructively? I have soaked these things in degreaser in a heated ultrasonic cleaner for hours. I have soaked them in carburetor cleaner (both Chem Dip and carburetor cleaner sprayed out of a can) in the ultrasonic cleaner for hours. NOTHING breaks the gunk up so that I can get spray or air through it. Surely there HAS top be SOME way to clean these without having to replace the bodies!?

Any help, advice, tips or tricks would be GREATLY appreciated here! Thanks.

 

[ILENGINE]

Normally that would be the bowl vent, but since that is a primer carb, and the bowl venting system is part of the primer system(angled hole on other side of carb on mounting flange, that hole needs to be plugged for the primer to work. So it is clogged on purpose.

 

[rebeltaz]

Normally that would be the bowl vent, but since that is a primer carb, and the bowl venting system is part of the primer system(angled hole on other side of carb on mounting flange, that hole needs to be plugged for the primer to work. So it is clogged on purpose.

I typically don't disagree with people who probably know more than I, but... in this case, you're mistaken. For one, on every carburetor on which I've come across this, the new replacement carburetor bodies were NOT clogged or plugged. Second, with this clogged, the engines were running rich until I swapped bodies with ones whose jet were not clogged. Finally, as I said, I am aware of the jet behind that ball which was clogged - not plugged - because I removed that ball from one of the carburetors. I had basically destroyed the body trying to get it out, as I mentioned, but there IS a jet that was CLOGGED behind that ball.

 

[Rivets]

IL is correct, that is the bowl vent, part of the primer system. The jet you are talking about is a metered air passage way.

 

[rebeltaz]

IL is correct, that is the bowl vent, part of the primer system. The jet you are talking about is a metered air passage way.

OK... be that as it may... metered air passage way or jet... whatever its called.. it is clogged.

 

[Scrubcadet10]

i always give it a generous high powered shot of carburetor cleaner after an ultrasonic bath and they come clean.
watch your face and eyes.

 

[rebeltaz]

Normally that would be the bowl vent, but since that is a primer carb, and the bowl venting system is part of the primer system(angled hole on other side of carb on mounting flange, that hole needs to be plugged for the primer to work. So it is clogged on purpose.

IL is correct, that is the bowl vent, part of the primer system. The jet you are talking about is a metered air passage way.

I wanted to take a picture of what is behind that ball. THIS is what is getting clogged


Since this sits BEHIND that ball and in an elbow, there is NO WAY to push anything through it.

 

[rebeltaz]

i always give it a generous high powered shot of carburetor cleaner after an ultrasonic bath and they come clean.
watch your face and eyes.

For every other jet or "metered passage" that works great. I do the exact same thing on all of them (except the "watch your eyes part" ... I always forget to do that until it's already too late )but this one sits behind a ball that the factory pressed in after drilling the passages and since it's in an elbow... nothing is getting through it. Carb cleaner; Chem Dip; ultrasonic cleaning; 90 psi air pressure... nothing. I cannot believe that I am going to have to keep replacing these bodies because of one hidden "metered passage."

 

[shadetree#1]

I've got some different size and type of needle tips (some tapered rubber and some are steel tipped that I can put on the end of my air nozzle and use high pressure air. Be sure and wear eye protection because if the clogg is on the opposite side of the ball, the ball during high pressure the ball might be blown out at high speed. I've used this method to clean out dried paint from small passages in spray guns after soaking them in acetone. Paint will come out like a small worm if constant pressure is held applied.
If this method does not give it relief I would probably take my Dremel grinder and I have some very fine sharp pointed bits similar to dental drills and carefully relieve around the ball for removal. I got some of the bits from a dentist (just ask for their dull root canal bits). I have to use a Dremel tool chuck adapter for their use. Re-sealing afterwards will require some thought. Them Walbro LM carbs are not cheap now days and some are NLA.

 

[StarTech]

Just center drill (using a carbide bit) the steel and extract it. Of course the next steel ball will need to used to replace it. I have done several on the horizonal engine tank mounted carburetor where the tower become clogged with rust.