Idle circuit blocked

Kawboy wrote:

I would also suggest you get a unit that runs at 40 Mhz. There are units that operate at 25 Mhz too but you'll find the higher frequency is better for cleaning metal parts.

 

40 Khz. right?

Yup, 40 Khz. My bad. Yesterday I  was staring at my Ohm meter testing  out a starter. My Ohm meter has 1 switch setting for Ohms, then the screen readout is in numbers with no decimal points and a symbol comes up on the bottom of the screen saying M Ohm or K Ohm. Needless to say, when hopping around the commutator ring with 2 probes and seeing the f...king symbol bounce between K and M, the brain thinks I'm  eating Alphabet cereal.

Sorry about that. 40 Khz is the right buy.

KB


As a post note - About every 2 months the wife hands me a bunch of jewelry  and asks me to put them through the ultrasonic cleaner. You've never seen diamonds sparkle until you've done this. Now the daughter caught sight of the wife's rings and remarked so the wife told her about the ultrasonic cleaner and for the past 2 years I've had to do her jewelry too. So for Christmas the daughter will be getting an ultrasonic cleaner from us similar to what I tagged in the previous post. 100 watt power with 100 watt heating = 200 watts total power.

RBY wrote:

I have heard of folk carefully drilling out the small brass balls opposite the elbow bends so you can get a straight run at the channels - has anybody done this successfully and know the diameter of replacement balls to bung 'em up again afterwards.

Daro did it 5 years ago just to see what was behind the port  machining access  points. No detail on the sizes of the balls. 

Daro lean mixture topic 2019

I've done this in the past on auto carbs. Just measure the diameter of the port where the ball sits first. Use that diameter drill bit and knowing that the brass ball is round, drill down the depth  = to the diameter of the hole to remove the ball. I've used lead shot to plug the holes afterwards. Know anybody in the shotgun reloading business?? That's where I sourced the lead shot. I'm sure I shouldn't have to say it but the lead shot should drop into the hole with maybe a tiny bit of persuasion, then tap on it with a pin punch to set and lock the lead shot in place.

"I have heard of folk carefully drilling out the small brass balls opposite the elbow bends so you can get a straight run at the channels - has anybody done this successfully and know the diameter of replacement balls to bung 'em up again afterwards"

IMHO: This would be the very last thing I'd even consider.  I would strip the carbs, remove the throttle shafts/plates/seals and soak the entire body in lacquer thinner.  A syringe with lacquer thinner can be used to purge all the fuel/air galleries and then use compressed air to blow out the passages.  =11.0ptYou can check the idle and transition ports for a strait stream (ideal flow pattern) by using a syringe to inject your solution into the pilot-needle port.  Repeat as required. You should start by flushing from the pilot-needle port.  After several flushing you can then purge in all directions. NOTE:  a 20-minute soaking should be adequate.  “Cellulous Thinners” will damage the aluminum if the parts are left in it over-night !   This typically deals with even the most stubborn of blockages/restrictions.  I like to use a tray of some sort to catch the fluid.  It's always interesting to see what flushes-out !

Owe you guys an update. Not sure the soaking for 20 minutes would do the job as I have squirted laquer in every few minutes for a couple of hours, then blasted with air. Rinse and repeat multiple times but no joy. Reference first photo below. The narrow plastic nozzle off a CRC can fitted nicely into the syringe and then tappered the other end to be flush with the idle passage exit in the emulsion tower. Used the football inflater attachment for the air compressor, a little electrical insulation on the tip to close off the side opening and fitted pretty snug against the idle fuel passage opening. This worked, eventually, on one blocked passage on #1 carb but wasn't making any progress on the second blocked passage on #2 carb. Then the repeated advice of wiser men kept echoing in my mind - flush in opposite direction of flow. So pondered on how to block off the bottom of the idle screw cavity. It ain't pretty (second photo) but got a small rubber plug (out of my hole punch for leather/rubber) that was a friction fit in the idle screw hole, tapped a small flat headed brad through so I could get the plug out later, easd it carefully into the idle screw cavity with brad sticking out. Then placed air compressor with rubber hose attachment over the brad and held it over the idle screw opening. One puff and it blew clear. Afterwards I thought I should have put a dab of liquid insulator on the head of the brad, to avoid potential damage to the idle screw seat, will do that for next time. Super easy and should have done it from the getgo. Hope it helps someone else.

Adaboy . Nicely done !! Now we have you thinking like a carb technician. Once you understand the flow of fuel / air through the carburetor, you can do your testing to figure out where the problem is and then come up with a way to fix the problem.

I'm not surprised that the passage going through the emulsion tube was blocked since it sits in the gas that is in the float bowl and as the gas evaporates or deteriorates, varnish would form. Now normally, those particles of varnish would want to flow down the path and then get stuck at the transition ports but in your case, I guess the varnish had time to build up and get stuck in the passage in the emulsion tube and you figured that out and came up with a way to clear that part of the circuit independently. Good for you !!

Thanks for sharing. I'm sure it will help out those that follow the writings here.

KB