Clogged Accelerrator Pump Nozzle

[Wez_]

You should see all the ninja hooks I've created to try and snake this nozzle. On the number 1 carb, the nozzle is plugged. Can i drill out the small brass ball underneath the nozzle on the base of the carb to grant access to the nozzle? Seems like the only way to access this thing. I've heated the nozzle with a torch and watched boiling solvent do nothing. The nozzle tip is cleared along with the rail hole. The clog is somewhere inside. Would CLR be ok to use?



If I drilled out that Brass plug, then will it grant access to the nozzle? I could then have the hole welded shut with aluminum? idk

 

[amc49]

You MUST have the check ball/valve still in place or your pump 'shot' simply goes backwards back into the fuel bowl. That is on the #2 carb (bowl I think) though and one only.

If talking about a brass ball used to plug a drilled passage (the kind used all over the carbs) yes you can but then the issue becomes one of plugging the passage to not leak again when done. I've done it before. Solder can be pressed in there or drilled/tapped for a small allen set screw.

 

[Wez_]

You MUST have the check ball/valve still in place or your pump 'shot' simply goes backwards back into the fuel bowl. That is on the #2 carb (bowl I think) though and one only.

If talking about a brass ball used to plug a drilled passage (the kind used all over the carbs) yes you can but then the issue becomes one of plugging the passage to not leak again when done. I've done it before. Solder can be pressed in there or drilled/tapped for a small allen set screw.

Ok, I added a picture like 1 minute before your reply. So there is one nozzle that has a check ball in the bowl of the carb? I have read through the carburetor rebuild write up numerous times and there was no mention of a check ball. Only a check valve.



So the carb that has the hole at the base gets a check ball in the bowl? Ill have to source an appropriate check ball as mine is long gone.

But yes, you can see in the second image above that there is a small brass plug that is directly below the AP nozzle. If I drill this out, clean the nozzle and replace with a threaded insert, I should be OK? ugh

 

[amc49]

The check VALVE can be either a ball or an actual little poppet valve, either one there is not free, rather trapped and spring loaded to seal in one direction only. Pump uses it open to suck fuel into pump then it seals to force the redirection of that fuel shot into the nozzles. It also prevents extra fuel pullover at faster carb flows that would otherwise mess up top end fuel metering. Correct, fuel goes through it one way only. There is NO extra ball there, and sorry for any confusion.

I would NOT weld the hole shut with heli-arc, too much chance of warpage going on there.

Yes, you can clean out the passage using that one location. Epoxy the replacement plug in, epoxy is not long term fuel safe but with the length of the setscrew epoxy coated it will take years to begin to leak there. Or solder in a big enough wire OD to cut a short piece to use as a formable plug using a small OD flat tip punch. The setscrew if used must be short enough to not block off needed part of the passage. If bowl clears it (can't remember) then let the extra fall outside the hole into outside air, no harm there.

You're in serious carb rebuild land now but not hard, just think it out and it'll be fine. You'd be amazed the numbers of carbs I've revived from the dead doing stuff that everybody is afraid of. Start out small with the plug hole you drill, you can always make it bigger.

 

[Wez_]

The check VALVE can be either a ball or an actual little poppet valve, either one there is not free, rather trapped and spring loaded to seal in one direction only. Pump uses it open to suck fuel into pump then it seals to force the redirection of that fuel shot into the nozzles. It also prevents extra fuel pullover at faster carb flows that would otherwise mess up top end fuel metering. Correct, fuel goes through it one way only. There is NO extra ball there, and sorry for any confusion.

I would NOT weld the hole shut with heli-arc, too much chance of warpage going on there.

Yes, you can clean out the passage using that one location. Epoxy the replacement plug in, epoxy is not long term fuel safe but with the length of the setscrew epoxy coated it will take years to begin to leak there. Or solder in a big enough wire OD to cut a short piece to use as a formable plug using a small OD flat tip punch. The setscrew if used must be short enough to not block off needed part of the passage. If bowl clears it (can't remember) then let the extra fall outside the hole into outside air, no harm there.

You're in serious carb rebuild land now but not hard, just think it out and it'll be fine. You'd be amazed the numbers of carbs I've revived from the dead doing stuff that everybody is afraid of. Start out small with the plug hole you drill, you can always make it bigger.

Thanks bud, this is great advice. I appreciate the clarification. You did say ball / valve. I also read a thread from the s.o.h.c forum that also referenced a ball that threw me off a little.

That stubborn accelerator pump nozzle finally cleaned up. It appeared to be solid varnish if you ask me. I finally found a wire that was small, solid and malleable enough to withstand being forced into the port from the rail. Once it was inside i poured the port with CLR and bubbles appeared one time so that told me i breached something and some chemical reaction was taking place (varnish) as opposed to a rock being stuck in there and just impossible to dissolve. So i kept repeating the laborious process of stripping back new wire, making the hook, forcing the wire in and adding CLR. FINALLY some black stuff bubbled out from the CLR eating away at it. I soaked it in CLR again overnight. Next morning inside the carb body was a blob of black "stuff" that finally went through the nozzle tip as fluid. Now it consistently squirts from the nozzle. Avoided the drill luckily.